78 Psyche [April 



3. At birth, the nymph is covered with a membraneous 

 envelope which usually ruptures when the former is partially 

 extruded through the vaginal slit. The nature of this envelope 

 is still in question. I infer from my own observations on Macro- 

 siphum tenaceti that the membrane arises from the egg-follicle, 

 which apparently does not degenerate. 



4. The nymph begins to feed in about fifteen to twenty 

 minutes after birth. 



5. The position of the mother during parturition is the 

 same as in feeding. Parturition apparently does not interfere 

 with the latter process. 



LITERATURE CITED. 



BAKER, A. C. 1915. The woollv apple aphis. U. S. Dept. 

 Agric. Rept. No. 101 : 1-56. PI. I-XV. 3 text-fig. 



BOUVIER, E.-L. 1919. La vie psychique des insectes. iv 

 30 pp. Paris: Ernest Flammarion. 



BUESGEN, M. 1891. Der Honigtau. iv 90 pp. PI. I and 



II. Jena: Gustav Fischer. 



GLASER, R. W. 1917. Anthocvanin in Pterocomma smithice 

 Mon. Psyche 24: 30. 



JANET, C. 1909. Sur I'ontogenese de I'insecte. 1-130. Li- 

 moges: Ducourtieux et Gout. 



MACCHIATI, L. 1883. La clorophilla negli afidi. Bull. Soc. 

 Entom. Ital. 15: 163. 



PRZIBRAM, H. 1906. Aufzucht, Farbenwechsel und Regene- 

 ration einer agyptischen Gottesanbeterin {Sphodromantis 

 hioculata). Ztschr. Entw.-Mech. 22: 149. 



1909. Aufzucht, Farbenwechsel und Re- 

 generation der Mantiden. Archiv f. Entw.-Mech. 28:561. 



WEBSTER, F. M., and W. J. PHILLIPS. 1912. The spring 

 grain-aphis, or "green bug." U. S. Dept. Agric, Bu. 

 Entom., Bull. No. 110: 1-153. PL I-IX. 48 text-fig. 



ZWEIGELT, F. 1915. Beitriige zur Kenntnis des Saugpha- 

 nomens der Blattlause und der Reaktionen der Pflanzen- 

 zellen. Centralbl. f. Bakt., 2. Abth., 42: 265-334. PI. I-II. 



1 text-fig. 



