Common Cockroach. 203 



teres^ pi. iv., fig. 42. The two infundibula pass veiitrally 

 to the terminal nerve structures and oviscapt, to form a 

 common vagina, which opens between the sterna of the 

 eighth and ninth abdominal segments, 

 J). •■ Colleterial ■" or 'sebaceous' glands of the left side. These 

 glands consist of long delicate tubules, the contents of 

 which are by no means always iiniform in colour. The 

 very numerous tubules of either side join a single stem, 

 and the two ducts thus formed pass down near the middle 

 line, and within the angle bounded by the nerves of the 

 last abdominal ganglion, to end within a single orifice on 

 the sternum of the tenth abdominal segment. Anteriorly 

 to the two colleterial ducts, and occupying the apical 

 portion of the angular space limited by the nerve structures, 

 may be found the receptacula seminis, which consist of two 

 short tortuous coeca, opening by a very short common duct 

 upon the sternum of the ninth segment. Spermatozoa are 

 said by Siebold to be found in both these coeca ; otherwise, 

 as one is of smaller calibre than the other, we might have 

 considered one to be a receptaculum seminis and unpaired, 

 as usual in insects, and the other to be a ' glandula appendi- 

 cularis,' such as is so frequently attached to the recepta- 

 culum seminis in other insects. In thus possessing two 

 receptacula seminis instead of one, as also in having eight 

 ovarian tubuli instead of twelve, as is usually the case in 

 Orthoptera, the Cockroach presents us with more or less 

 aberrant arrangements. Figures of the various forms which 

 the female generative organs may assume in the Orthop- 

 terous Termes Lucifuyum, may be found in the plates ap- 

 pended to M. Lespes' memoir upon that species, in the 

 Annales des Sciences Naturelles, Ser. iv., tom. v., pi. 6, 

 figs. 24-27, where the colleterial glands and receptaculum 

 seminis will be seen to present much the same arrangement 

 as that which has here been described in the Cockroach. 



For the morphology, anatomy, and development of Insecta, the 

 numerous memoirs by Sir John Lubbock, in the Transactions 

 of the Royal and Linnaean Societies from 1857 onwards, 

 should be consulted. Amongst these, see for Parthenogenesis 



