SPERMATOPIIORES IX ICARTlIWOnMS. 415 



apparatus. Although one might suppose that in two genera, which 

 are probably to be i-egai'ded as nearly akin, the formation of the 

 spermatophores Avould be identical, there is in the Pheretiina now 

 under considexutiou some positive evidence to show that the 

 spermatophores ai'e formed in the tei-minal sac of the male 

 ejaculatory apparatus. In this species, as in other Pheretimas, 

 the spermiducal gland ends in a narrow muscular duct which 

 apj)ears to oj^en into a wide terminal bursa copulatrix. The 

 latter, of course, opens on to the eighteenth segment by a 

 conspicuous orifice. When sections are made through this 

 tei-minal apparatus it is seen that the cavity of the bursa 

 copulati'ix is by no means so large as the periphei-al measure- 

 ments of the sac would lead one to imagine, but that the 

 greater part of its cavity is occupied by a large penis, A\'hich can 

 doubtless be protruded. This penis, which is of a conical form, 

 is surrounded by the cavity of the bursa, which, however, lies 

 chiefly to one side, and there is in that region, therefore, a space 

 of moderate dimensions which is not far from the size of one of 

 the spermatophores. Furthermore, the cells which line this cavity, 

 except near to its external orifice, are tall, and the glandular- 

 looking cells stain badly, and thus appear to be full of 

 some hardly stainable secretion. The muscular duct leading 

 from the spermiducal gland is joined at about the end of the 

 first fourth of the penis by the sperm-duct (here single and 

 apparentlj' not ciliated), and the conjoined duct opens not on 

 to the end of the penis, but rather to the side, i. e. inside the 

 cavity of the bursa copulatrix, so that it might inject the 

 sperm into the cavity of the bursa. This sperm might then be 

 surrounded by an excretion of the glandular cells of the bursa, 

 and thus emerge a complete and fully charged spermatophore. 

 This is admittedly a mere suggestion, and is far from being a 

 conclusive statement. I have, however, no further evidence. 



Reverting to the spermatophores themselves, they show, when 

 examined entire with a low power of the mici'oscope, an opaque 

 appeai'ance, less marked naturally at the free tail-like termination. 

 The opacity is doubtless responsible for the white appearance of 

 the body, and is very different from what one would expect in a 

 spermatophoi'e. Presumably with chitinous walls it would 

 be supposed that it w^ould present a transparent, or at least 

 translucent, appearance when examined by transmitted light. 

 This is, however, not the case at all. Moreover the walls of the 

 spermatophore have not a regular outline, but are roughened, as 

 if many minute particles were adherent to the outside. This is 

 not in any way different when the bodies are examined ia 

 glycerine. The roughened and opaque exterior prevents a clear 

 view of the contained sperm, and, indeed, it would be impossible 

 to state from such an examination only that there was any sperm 

 within. Viewed in its entii-ety in glycerine not much more is 

 to be learnt about the si^ermatophore than is taught by an 

 examination of it as an opaque object with a lens. I have. 



