1911] Severins — Care of the Eggs and Rearing of the Wal king-Sticks 123 



placed the eggs, "siir du sable fin dans une boite couverte par une 

 feuille de papier buvard epais. La boite fut mise dans une cage 

 en treillis, dans une serre, dont la temperature normal varie entre 

 18 et 20° C, et le papier buvard humecte chaque jour, afin de 

 donner aux oeufs, sans les mouiller, une certaine humidite." 

 Other naturalists, who hatched the eggs of various species of 

 Phasmids, used a wet sponge to supply the eggs with moisture. 

 In our work with Diapheromera, the eggs were kept upon fine lake 

 sand which was sprayed with water whenever it became too dry. 

 Attention has already been called in a previous paper (6) to the 

 fact, that if the sand is kept too dry, especially at the time of 

 hatching, many walking-sticks fail to emerge completely from the 

 eggs. If the eggs are kept in a well aerated breeding cage, molding 

 can be prevented. 



BIBLIOGRAPHY. 



1. V. Baehr, W. B., 1907. Uber die Zahl der Richtungskorper in parthenogentisch 



sich entwickelnden Eiern von Bacillus rossii. Zool. Jahrb. Anat. XXIV, 

 pp. 175-191. 



2. Daiber, M., 1905. Beitriige zur Kenntniss der Ovarien von Bacillus rossii 



Fabr. nebst einigen biologischen Bemerkungen. Jena Zeit. f. Naturw. 

 XXXIX, pp. 177-^02. 



3. Godelmann, R., 1901. Beitriige zur Kenntnis von Bacillus rossii Fabr. mit 



besonderer Beriicksichtigung der bei ihm vorkommenden Autotomie und 

 Regeneration einzelner Gliedmassen. Arch. Entmech. XII, pp. 265-301. 



4. Kheil, N., 1900. Biologisches iiber Bacillus rossii. Ent. Zeit. No. 16 u.l7. 



5. Morton, W., 1903. Notes sur I'elevage des Phyllies. Bull. Soc. Vaud. Sci. 



Nat. XXXIX, pp. 401-7. 



6. Severin, H. H. P. and Severin, H. C, 1910. The Effect of Moisture and Dryness 



on the Emergence from the Egg of the Walking-stick, Diapheromera femor- 

 ata Say. Jour. Econ. Ent. Ill, No. 6. pp. 479-481. 



7. 1911. The Life-History of the Walking-stick, Diapheromera 



femorata Say. Ibid. IV, No. 3. 



