. Circulaire. Les insectes nuisibles ; les insectes nuisibles. Tin 18}^ l'oeuf. Cet œuf éclot dans un hirva dans un peu d'argiles, et la position habituelle dans le corps du "bug" vert de l'hirva jusqu'à l'époque elle est pleine-groAA'n'est montré en Fig. G, page 4. Jusqu'à tliis temps qu'il a nourris à l'intérieur du corps de la " green bug" sans atteindre l'une des parties vitales, mais prévenir à un plus grand ou moindre degré le don de naissance aux jeunes. C'est un fait important, car, comme le parasite semble préférer les jeunes en partie, il commence à vérifier l'augmentation de l'organisme nuisible avant la mort de la " green bug

• Contributeur: The Book Worm / Alamy Banque D'Images
• ID de l’image: REM2P3
• Taille du fichier: 7,1 MB (223,6 KB Téléchargement compressé)
• Autorisations: Modèle - non | Propriété - non
• Dimensions: 986 x 2534 px | 8,3 x 21,5 cm | 3,3 x 8,4 inches | 300dpi

Informations supplémentaires

Cette image appartient au domaine public, ce qui signifie que le droit d’auteur a expiré ou que le titulaire du droit d’auteur a renoncé à ses droits. Les frais facturés par Alamy couvrent l’accès à la copie haute résolution de l’image.

Cette image peut avoir des imperfections car il s’agit d’une image historique ou de reportage.

. Circular. Insect pests; Insect pests. 18 tin}^ egg. This egg hatches into a hirva in a few clays, and the usual position in the body of the "green bug" of the hirva up to the time it becomes full-groAA'n is shown in fig. G, page 4. Up to tliis time it has fed within the body of the " green bug" without reaching any of the vital parts, but preventing to a greater or less degree the giving of birth to young. This is an important fact, for, as the parasite seems to prefer partly grown young, it begins to check the increase of the pest before the death of the " green bug " takes place. Mr. Phillips has found that females parasitized at this period of their development do not reproduce for more than a very few days. After about six daj^s the larva of the parasite reaches full growth and becomes more active, working its way about within the still living body of its host, which now dies a seemingly terrible death. The motions of the parasitic larva within cause the skin of the " green bug " to become rotund in shape, as shown in fig. 9; the skin also becomes darker and hardens. Within four days (the life cycle in warm weather occupying about ten days) the adult Lysiphlebus emerges through a round hole in the dried skin of the " green bug, " as shown also in fiig. 0. In fields that have been destroyed the leaves become almost covered by their brown bodies, as shown in fig. 7. As stated, many of the " green bugs " are stung by the Lysiphlebus while quite 3'Oung, and if these develop to winged adults, as they do at times in myriads and drift away to distant fields, they carry the parasite with them in their bodies. One of these parasitized winged females is shown in fig. 10. The very act of migration of the " green bug, " therefore, brings the parasite, and there is no need of artificial introduction, for if the center from which the " green bug " is migrating has the para- sites, as it always doe

Recherche dans la banque de photos par tags

• bookcentury1900
• bookdecade1900
• booksubjectinsectp
• bookyear1904