The Shipley Collection of Scientific Papers, Volumen2981887 |
Pasajes populares
Página 21 - June, or about the time of the blossoming of the damask rose, and remain from thirty to forty days. At the end of this period the males become exhausted, fall to the ground, and perish, while the females enter the earth, lay their eggs, return to the surface, and, after lingering a few days, die also.
Página 4 - That the fungus of the house-fly works as well as yeast for baking and brewing purposes. 3. That the application of yeast on insects produces in them a fungus which becomes fatal to the insects. 4. That, in the experiment made by Mr. JH Burns, all potato beetles sprinkled with diluted yeast died from the eighth 10 to the twelfth day, and that the fungus was found in the vessels of the wings.
Página 21 - In the spring they approach toward the surface, and each one forms for itself a little cell, of an oval shape, by turning round a great many times, so as to compress the earth, and render the inside of ' the cavity hard and smooth. Within this cell the grub is transformed to a pupa, during the month of May, by casting off its skin, which is pushed downward in folds from the head to the tail.
Página 116 - From all the above facts I infer that all our species that are found only in the female sex are represented in another generation by both sexes, and that the two broods are, owing to seasonal differences, produced from galls, that are entirely distinct from each other.