90 Descriptions of Preparations. 



entitled 'Beitrage zur nahern Kenntniss von Periplaneta 

 (Blatta) Orientalis/ von C. Cornelius, Elberfeld, 1853. 



For an account of the various g-lands superadded to the essential 

 organs of the female reproductive apparatus, see Siebold, in 

 Miiller's Archiv. for 1837, p. 393 seqq., and for their arrange- 

 ment in Blatta (Periplaneta) Orientalis, p. 408. For figures of 

 a female reproductive apparatus essentially similar to that here 

 described, see Lespes^ account of the Termes Lticifugum, Ann. 

 Sci. Nat. Ser. iv., Tom. v., PI. 6, fig. 24-37. For the orifices 

 of the various ducts in the reproductive apparatus, see Hux- 

 ley, Linn. Soc. Trans., vol. xxii. p. 231. For the 'suspensory 

 ligament' of the ovary, see Stein, ' Vergleichende Anatomie 

 und Physiologic der Insecten,' pp. 36, 41-43; Miiller, Nova 

 Acta, xii., pt. ii., p. 578. For the composition of the 'oviscapt' 

 and the number of the abdominal somites, see Lacaze Duthiers, 

 Ann. Sci. Nat., Ser. iii., torn, xvii., 1852, p. 227 ; tom. xix., pp. 

 229-233, and Huxley, Linn. Soc. Trans., vol. xxii., 1858, p. 231. 



For the development of the fat body independently of the yolk, see 

 Elias Metschnikow, ' Embryologische Studien an Insecten,' 

 p. 73, and for its connection with the production of phospho- 

 rescence in such insects as the Lamppis splendidula, see Leydig, 

 ' Lehrbuch der Histologic/ p. 342. 



For a description, with figures, of the stomatogastric nervous 

 system, see Brandt, Ann. Sci. Nat., Ser. ii., tom. v., 1836, 

 p. 103, pi. iv., figs. 4, 5. 



For Bibliographical references, see Scudder, Smithsonian Institu- 

 tion's Catalogue of Orthoptera, Washington, i868, pp. 17-63. 



31. Common Crayfish {Astacus Fluviatilis), 

 Female. 



This Crustacean's body consists of two great divisions, the 

 so-called ' cephalo-thorax,' covered dorsaUy and at the sides by 

 a carapace, and carrying fourteen pairs of articulated appendages, 

 and the post-abdomen consisting essentially of six definitely an- 

 nulate and calcified segments, to the posterior one of which a 

 powerful natatorial organ, the 'swimmeret,' is articulated. The 



