ment generally batter themselves to death within two days. The penis is telescopically extensile to about twice the length of his body, and he is thus enabled to reach the female without difficulty.

This insect is essentially polyphagous, for it occurs alike on evergreen and deciduous trees. We have found it on the red and white elms, the common black and honey locusts, Lombardy poplar, catalpa, Norway spruce, arbor-vitæ, osage orange, soft and silver maples, sycamore, apple, plum, cherry, quince, pear, linden, and, above all, on the red cedar, while Mr. Glover has also found it on the cotton plant in Georgia. We have even seen the bags attached to raspberry canes; but the Ailanthus, which is now extensively grown in our large cities for shade and ornamental purposes, will be found entirely exempt from its attacks. There seems to be a very general prejudice against this tree on account of the rather unpleasant and fetid odor of the male blossoms, and we were much surprised at the wholesale tirade against it, that was made by the editor of the Horticulturist in 1869 in the August number of that journal. In view of the fact that it is so free from the attacks of injurious insects, we deem it well worthy of cultivation; and those who do not like the odor of the male blossoms, ought to know enough, either to cut them off at the proper time, or to grow only the female tree which produces no unpleasant effluvium, and which, with its large cluster of seed-pods-now yellow, now assuming almost every tint from flesh-color to crimson-forms, in our eyes, a most graceful and pleasing sight. In 1868 we had noticed that this tree when surrounded by other kinds, would have a few isolated bags hanging from its twigs, and it became a question in our minds whether the Bag-worm actually disliked the leaves, or whether the leaves being compound, its usual instinct failed it, insomuch that it fastened its case to the mid-stalk, which falls to the ground. But after ample experiment the past suminer, with worms newly hatched and with others of various ages, we have concluded that they cannot live on Ailanthus leaves, and that such few bags as are found upon this tree in winter, have been fastened there by worms which had traveled from other kinds of trees.

This insect is also exceedingly hardy aud vigorous, and the young worms will at first make their bags of almost any substance upon which they happen to rest when newly hatched. Thus, they will construct them of leather, paper, straw, cork, wood, or of any other material which is sufficiently soft to allow of their gnawing it,

and it is quite amusing to watch their operations.

Remedies.

How often does the simple knowledge of an insect's habits and transformations, give the clue to its easy destruction! From the foregoing account of the Bag-worm, it becomes obvious, that by plucking and burning the cases in the winter time, the trees can be easily rid of them. If this is done whenever the first few bags are observed, the task of plucking is light; but where it is not so done, the worms will continue to increase, and partly defoliating the tree each year, slowly, but surely, sap its life.

This

For many years this insect had been multiplying in the city of St. Louis, until in 1868 it had become exceedingly abundant and destructive, especially in the older portions of the city. So many trees were unhealthy, and dwindled or died, that tree planters frequently became discouraged. Very few persons, however, suspected that the Bag-worm was the cause, and still fewer were aware how easily its ravages were checked, until last winter, the Junior Editor called attention to the matter through the columns of one of the daily papers, and urged the destruction of the bags and their contents before the trees again put forth their leaves. appeal, we are glad to say, was duly responded to by the citizens; for in less than a month, the trees in the public parks and around the court-house, and also along many of the streets, were entirely cleared of the bags. Indeed, we have seldom known entomological information to be fraught with such immediate and beneficial results! It even opened up a new field of employment for certain enterprising youths, who, with a dirty copy of the daily already referred to in hand, might have been seen trotting up some of the principal avenues, and shrieking out, newsboy fashion: "Clean your Bag-worms off, ma'am." "Clean your trees, sir?-take 'em all off for a dollar!"

Though the very first efforts of the newlyhatched worm are directed to building for itself a covering, and though, throughout its larval life, it is always covered and protected by this covering, this insect is yet subject to the attacks of parasites, two of which are already known to assist us in subduing it.*

*Cryptus inquisitor, Say, and Hemiteles thyridopteryx, Riley.

The publishers of those papers which advertise to club with ours, will please take notice of our change of subscription price.

TENT-CATERPILLARS AND FALL WEB-WORMS.

The following appears in the Western Rural of August 26, 1869, from the pen of a correspondent:

The Tent Caterpillar has taken possession of many fine young trees, and spread his web from "pole to pole," for many are stripped of foliage and resemble bare poles.

The true Tent Caterpillar, or as it is often briefly called, "The Caterpillar," hatches out in the spring almost before the leaves of our apple trees put forth. Early in June they spin up, and the moths, which are of a reddish brown color, make their appearance early in July, shortly after which they deposit their eggs in the well-known rings on the twigs, of which we gave a drawing (Fig. 145 c) on page 208 of our first volume. The Fall Web Worm, on the contrary, does not hatch out till August, and although it makes a very similar web-like nest to that constructed by the preceding species, it is yet a much smaller insect and somewhat differently colored. Towards the end of the summer this worm spins up like the true Tent Caterpillar; but instead of the Moth bursting forth from the cocoon the same season, it does not make its appearance till the middle of the following season. Moreover this moth, instead of being reddish brown, is of a pure milkwhite color, and it does not lay its eggs in a ring upon the twigs, but deposits them in an irregular mass upon a leaf. Thus it will be seen that one insect hybernates in the egg state, the other in the pupa state: one larva appears in May, the other in August; one moth is brown, the other is white; and one lays its eggs on the twigs, because if it laid them on a leaf they would fall off the tree and be lost in the winter, whereas the other species lays its eggs on a leaf, because it is instinctively aware that those eggs will hatch out long before the leaf falls to the ground.

No two insects are more frequently confounded than the true Tent Caterpillar (Clisiocampa americana, Harris), and the Fall Web Worm (Hyphantria textor, Harris); so that the correspondent of the Western Rural will find plenty of company in the mistake that he has made, in speaking of Tent Caterpillars in August. Both species are very general feeders, the nests of the Tent Caterpillar being found on the Wild Black Cherry, the Apple, the Crab, the Choke Cherry, the cultivated Cherry, the Plum both wild and tame, the Thorn, and the Shad bush, but scarcely ever on the Pear or on the Peach; while those of the Fall Web Worm occur in the greatest abundance on Hickories,

especially the Pignut Hickory, and also on Wild Black Cherry, Apple, Crab, Ash, Elm, Willow, Oak, Birch, and Sycamore or Buttonwood.

EXPERIMENTS WITH THE JAPANESE SILK-WORM. (Antherea Yama-mai.)

BY W. V. ANDREWS OF NEW YORK.

In the year 1868 I made some experiments in rearing the Ailanthus Silk-worm (Samia Cynthia), an account of which appeared in the American Naturalist, in the August number of that year. I was of opinion then, and am now, that Cynthia is the moth best adapted to our northern climate as a silk-producer. My reasons need not be repeated here, but I may say that, since writing the article above adverted to, I have received from Dr. Wallace, of England, a specimen of sewing silk made from the cocoon of the Cynthia, and its appearance and quality have strengthened my previous favorable opinion.

By way, however, of ascertaining the species of silk-worm moth most suitable to the climate of North America, I obtained from Dr. Wallace a number of the eggs of the Japanese silkworm known as Yama-mai, which is said to produce a most beautiful silk, of a greenish color, and the cocoons of which are as easily rceled as are those of the ordinary silk-worm (Bombyx mori). These eggs were sold to persons residing in widely distant localities, while I reserved a considerable number for my own

use.

I propose in this paper to give the readers of the ENTOMOLOGIST not only an account of my own experiments with this insect, but also a synopsis of the results of the experiments of my correspondents, so far as I have been able to ascertain them.

The whole of the eggs I received from England arrived in New York in the months of March and April. I am inclined to think that this is a bad time to receive them here, and that in future it will be better to receive them in the fall, so that they may be forwarded to their respective destinations before the severe cold sets in, thus enabling parties living in widely distant latitudes to keep their eggs at a temperature which, without injuring the egg, will retard the hatching till such time as vegetation in their respective localities shall be so far ad· vanced as to afford the caterpillars a good supply of food. If the eggs be kept in England till early spring, it is clear that they will be somewhat developed by the warmth of the climate,

which development may be seriously checked if the temperature here should be, as it probably would be, much lower than the temperature of England. Disease may be thus induced; and my opinion is that most of the failures occurring here this last season may be attributed to this

cause.

It will be perhaps remembered that the spring of 1869, at least on the Atlantic coast, was very backward. The consequence was that, when on April 26th some of the Yama-mai eggs began to hatch out, there was nothing worthy of being called an oak-leaf to be found for them. The few warm days occurring at this time were sufficient to complete the development of the caterpillar, but not sufficient to make the necessary advance in the growth of its food-plant. Buds, rather than leaves, of Quercus coccinea were however obtained, and upon these the larvæ fed a little. Still they were very sluggish and inert, and the weather again becoming very cold, most of this first lot died within the first two days. Dr. Wallace recommends that the larvæ be removed, as they hatch out, to strips of glass moistened with water so that they may drink. A better plan is, I think, to remove them at once to branches, the leaves of which have been well sprinkled. Moisture in some way should, I have no doubt, be furnished them.

By May 3d nearly all the caterpillars, amounting to over a hundred, had died from the prevalence of cold. I was obliged to keep them within doors, and they appeared to eat a little during the day; but they became torpid during the night, and in the morning were all but inanimate. The temperature had ranged from 40o on April 26th to 58° on the 27th, and by May 3d had gone down again to 35o.

By May 12th more eggs had arrived from England, and the weather having become somewhat warmer, hatched out almost immediately. These I fed on Q. coccinea and Q. tinctoria indifferently, the larvæ evincing, I think, a little preference for the former, but doing well on both. The branches were placed in water, under a verandah facing the northeast, so that the rays of the morning sun had access to them, the larvæ appearing to enjoy the warmth. I kept them out night and day, unless the night threatened to be very cold. In warm dry days I sprinkled the branches two or three times with clear water. A short description of the larvæ may not be out of place here.

On hatching out they are brimstone yellow; the body sparsely covered with strong hairs. After the second moult they become greenish,

with black spots. After the third moult the color is a beautiful apple-green, with yellow tubercles on each segment, and a few black hairs emerging from each tubercle. The head and legs are chocolate brown, the pro-legs reddish. On the anal legs there is a dark brown or nearly black patch. The first segment is edged with deep pink. In some lights a silver spangle appears on some of the tubercles. The markings do not greatly differ during the remainder of their growth, but the apple-green color becomes, if possible, still more beautiful.

It is almost impossible to imagine weather more unfavorable for the rearing of any foreign insects, than that which prevailed in New York during the months of April and May. I have already noticed this, but it may be well to quote from the record a little farther. On April 26th the thermometer at 6 A. M. stood, as I said before, at 489; at 3 P. M. it was 71o. On the 27th it was 58o in the morning and 72° in the afternoon, while on the 30th the mercury scarcely reached 55o in the hottest part of the day. On the 2d of May it reached no higher than 41o, keeping quite cold up to about the 22d, when it ranged from 49o at 6 P. м. to 62o at 3 P. M. On the 31st it reached as high as 790. Dr. Wallace tells us that the temperature most favorable to the welfare of the larvæ is from 50o to 60° in May and 65° to 75o in June, and thinks that a higher temperature "endangers the safety of the worm." Now, in June we had a series of hot days, in which the mercury reached over 86o. The consequence of all this was, that on June 25th, out of about 200 larvæ which had been a few days before apparently thriving, having reached their last moult, all but six were dead. A few may have wandered, and about three died of diarrhea, but the majority died of a disease acting very rapidly, which showed itself first in brown patches, generally on the second and third segments, but which soon afterwards extended over the whole body. Dr. Wallace informs me that in England, this year, Yama-mai has generally failed; the larvæ dying of a disease displaying symptoms similar to those above named. In some cases the larva eats a little after the disease becomes manifest, then suddenly stops, and a few hours afterwards it is seen hanging down from its anal legs a flaccid mass of corruption. A pale green fluid has by this time escaped, generally from between the first and second segments; and all that remains of the once beautiful caterpillar is an empty skin.

Most of my correspondents have also been unfortunate. In some cases the eggs hatched out

all right, but the larva were so weak that they were unable to feed. On the other hand, individuals who had obtained eggs out of the same lot found no difficulty in getting their larvæ to eat, and for a time to thrive well. So it should seem that, as I hinted before, the temperature at which the eggs are kept may have a good deal to do with the health of the future caterpillar.

Most of us who have been in the habit of raising caterpillars have doubtless met with similar instances where they have refused to eat. Even this year I have seen such in the case of a brood of the Royal Horned-Caterpillar that refused to eat a particle, and of course all died. But even here it is possible that the eggs may have been kept too cool or too hot; and it must be borne in mind that, although I attribute the failure of my Yama-mai to the unfavorable weather, I have by no means forgotten that disease may have been superinduced by the maltreatment of the eggs. Illustrative of this point are two remarkable cases involving one exception to the general failure of the Yama-mai crop to which I have already alluded.

A friend of mine, in Brooklyn, wishing to make sure that his eggs should not hatch out prematurely, placed them in an ice-house where the temperature was about 40°; and the consequence was that not a single caterpillar appeared. Yet a quantity of B. mori eggs, placed in the same situation, hatched out, thus showing that Yama-mai eggs cannot be exposed with impunity to a degree of cold that may be harmless to species duly acclimated.

On the other hand, a correspondent in Massachusetts, being also desirous of shielding his eggs from harm, placed them in a glass in his bed-room. The servant, however, objected to this littering up," and took down the glass to wash it out, throwing the whole of the eggs into very hot water. My friend was just in time to rescue two eggs, both of which hatched out; the caterpillars grew and flourished, and in due time formed beautiful cocoons; and, strange to say, this is the only instance, with an exception to be noticed presently, in which any of my correspondents have this year been successful in rearing Yama-mai. Au extract from his letter may be of interest:

"The eggs hatched out May 21st, and on the 14th of July I had one cocoon fully formed, and on the 21st the other. One of the larvæ was much larger than the other, and had five silvery spots on each side, while the other had only two; so I think I have a male and female. The worms were kept in a room facing the south, with

doors and windows open, night and day. Highest temperature 989; lowest 55o, Fahr."

The other successful instance occurred with the young ladies of the Academy of the Sacred Heart, at Manhattanville, New York, who have had the good sense to introduce the study of entomology, and I believe the other natural sciences, into their admirably conducted school.

One would infer from these facts that, as the time for hatching out approaches, the egg should be exposed, not to direct sunshine, but to a good degree of heat; and this treatment would seem to be the more necessary if, as is generally supposed, the caterpillar is fully formed in the egg shortly after laying, and one can also see why any great or sudden change to a low temperature is injurious to the egg.

A word now as to the food-plant and manner of feeding.

I have little doubt that Yama-mai will feed on any kind of oak, and it is stated in Dr. Wallace's report that they will feed on apple tree. Nay more, that some larvæ which refused "ever green and other fancy oaks," did well on apple. More experiments are required in this direction, for it is quite possible that a change of climate may necessitate a change of food.

One thing struck me during the feeding of my larvæ, and that was that they seemed to be very lazy, inert fellows, preferring to feed on a half-dead leaf to taking the trouble to crawl to a fresh one near at hand. I believe that this eating of half-dry food is injurious, and generally removed the caterpillar, dry leaf and all, to pastures new. But it must not be forgotten that in Dr. Wallace's report it is asserted, that moist succulent leaves do not appear to agree so well with the caterpillar as well grown, fully developed leaves, even if they should be a little dry. More experience is required here.

It is perhaps not worth while to go more fully into details in this paper, when the experiments of another season may be productive of very different results; but I may say that, notwithstanding these almost complete failures, I have no doubt that both Yama-mai and Pernyi will in due time be acclimated in this country, and form another source of wealth for our energetic and enterprising people. If a number of individuals could succeed in raising a few cocoons each, we may, by making a collection from each, succeed in bringing together a number of males and females sufficient to secure a few lots

A subsequent letter from this correspondent informs me that his moths have come out male and female, and that the larvæ were fed on Red Oak (Q. rubra). Food changed twice a week, branches sprinkled daily; and that they were kept at an open window facing the southeast, with a curtain placed so that the early morning sun only, could fall on them.

of fertile eggs, and doubtless caterpillars from these would be healthier, and consequently would feed better, and be less predisposed to disease than those produced from imported eggs.

The great objection hitherto to the cultivation of Cynthia is the difficulty of reeling off the cocoons. As I said before, no difficulty of this kind occurs with Yama-mai; for Mr. J. P. Murray of England, to whom I am indebted for a valuable pamphlet on silk-worms, has succeeded in reeling 250 yards in one continuous thread from this cocoon, and is of opinion that 350 yards may be obtained. This is encouraging, and it would seem very strange if none of our silk manufacturers can discover a plan by which large quantities of this silk may either alone or mixed with other staples, be profitably made up into at least coarse goods for ordinary wear, for umbrella covering, or for a variety of other articles of that nature.

For those intending to make experiments next season with Yama-mai, it is desirable that they should this fall house some young oak trees, so as to be prepared with early food in case of premature hatching of the egg. They should also ascertain the localities of the earliest budding oaks, there being doubtless a considerable difference in the time of carly vegetation. It was stated before the Royal Dublin Society in November last, by Messrs. Moore and Andrews, that at Killarney Q. sessiliflora came into leaf full a month earlier than any other species.

Over our widely extended country it is scarcely possible that any one species of oak has the advantage universally over all others; but it would be of service to amateur silkgrowers, if the botanists would help us on this point by stating what species are earliest in different latitudes.

[Our own experience the past summer with this Japanese Silkworm was very unsatisfactory, and we learn from Dr. Wallace that experimenters met with but poor success in England in 1869, though an Austrian Baron succeeded in rearing 20,000 cocoons.-EDS.]

NEW FOOD FOR SILK-WORMS.-The Illustrated Sidney News (Australia), says that a native shrub has just been discovered both on Phillip Island and the shores of the western port bay, which has proved far better for feeding silkworms than the Mulberry.

To all persons interesting themselves in the American Entomologist we will allow twentyfive cents on every dollar, on all over five names which they send.

THE BOLL-WORM OR CORN-WORM.- 2d ARTICLE.

(Heliothis armigera, Hübner).

In number 11 of our first Volume we gave an account of this insect, illustrated by figures. In this Article we stated that it fed in the larva state on the bolls of the cotton plant, on the silk and the soft kernels of roasting ears of corn, and also on green tomatoes and young pumpkins. From the following passage in an Address on Insects, delivered at Vineland, N. J., by that excellent observer, Mrs. Mary Treat of Vineland that place, and published in the Weekly of August 21, 1869, it appears that this very same larva also feeds upon the undeveloped tassels of corn and upon green peas; and, as will be subsequently shown, it likewise bores into the stems of the garden-flower known as Gladiolus; and in confinement will even eat ripe tomatoes. Thus it seems to be almost as promiscuous in its tastes as the Stalk-borer (Gortyna nitela, Guen.), which burrows in the stalks of the Potato, of the Tomato, of the Dahlia, of the Aster and other garden flowers, of the common Cocklebur and of Indian corn, besides boring into green corn-cobs and eating into green tomatoes and ripe strawberries, and in a single instance in Missouri eating into peach twigs, and in Illinois inhabiting the twigs of the Black Currant.*

This year green peas have been eaten into by a hateful looking worm, and a similar one ate into the staminate flowers of the corn before it tasseled out, commencing their depredations while the tassels were still enfolded in the leaves. I have examined considerable corn, and in some gardens this worm has done much damage. While feeding it is of a green color; but when it comes to full size it turns brown, and goes into the ground to assume the chrysalis form. I already have the moths of the caterpillars that lived upon the peas, and am waiting for those that lived upon the corn to make their appearance, so that I may decide whether they are distinct species. It is a query with me what the second brood of caterpillars will live upon, as green peas and untasseled corn will be out of their reach.

There can be no doubt about the identity of the moth, the larva of which fed upon peas, because Mrs. Treat obligingly forwarded to us in the middle of August specimens actually bred by her from green peas, which differ in no respect from the common type of the Corn-worm moth. Unfortunately, she has mixed together promiscuously the moths bred by her from green peas and those which she subsequently bred from corn-tassels; but at our express de*See AMER. ENTOM., I, p. 206; II. p. 13.