240 W. WESCHE ON THE MALE GENITALIA OF THE COCKROACH, 



series of pieces which form the containing apparatus; besides 

 the part at the base of the left forceps which carries the remnant 

 of the palpus, and which is homologised as part of the theca, 

 there is a convoluted plate below (Fig. 9), a cover which is very 

 prominent on the right side (Fig. 6), a plate which forms an 

 upper part (Fig. 12), and a dome-shaped piece (Fig. 11) which 

 contains an articulation to the convoluted plate (Fig. 13). These 

 parts form connections to those attached to the forceps; they do 

 not readily separate when dissected out, and are apt to break 

 and consequently difficult to study. 



The convolute plate has some part of the surface roughened 

 with minute scale markings ; a similar structure has been noted 

 on the left paraphallus and on the part that represents the 

 orifice of the penis. This suggests itself to me as a surface 

 to which a semi-viscid body would cling, yet not stick, probably 

 regions of contact with the spermatophore. 



(p) Ejaculatory apodeme. — This is a shield-shaped piece with a 

 strong chitinous process running down the middle for the attach- 

 ment of muscles; it is situated in the centre, and appears to 

 work the cover. From its structure and situation I feel fairly 

 sure of the homology of this part, and it is consequently a useful 

 guide (Fig. 10). 



Interior organs. — These are comparatively simple, and are 

 amply explained in Professor Miall's and Mr. Denny's excellent 

 monograph (already quoted), and in the late Professor Huxley's 

 work on the Invertebrata,* to which I refer those who wish 

 to study these parts. 



Conclusion. — It remains to say that regarding the whole organ 

 as a piece of mechanism, it may be divided into four parts ;. 

 (1) a tube for the passage of spermatozoa into the containing 

 apparatus, and a gland (Prof. Miall's conglobate) for the pro- 

 duction of some semi -viscid fluid, used in the formation of the 

 spermatophore ; (2) the combination of the theca and hypophallus, 

 penis, and paraphalli, bending over to place the orifice of the 



The Anatomy of the Invertebratcd Animals, T. H. Huxley, 1877. 



* 'T 



