790 CONTRIBUTION TO AUSTRALASIAN OLIGOCH^TA, I., 



tion. In Phreodriloides, no spermathecse or spermathecal pores 

 are to be found, but the male efferent apparatus is peculiar. In 

 his description of that genus, Benham remarks : — " In all species 

 of Phreodrilus, the spermatheca exists in the form of a long sac 

 which extends through two or more segments, and opens near the 

 anterior margin of segment xiii." 



In Phreodriloides, the spermduct passes into the neck of a 

 large muscular sac into which it opens. There is nothing of a 

 glandular nature in the structure of the sac itself, or in associa- 

 tion with it. The neck of this muscular sac opens into a penial 

 chamber which, according to Benham, "appears to be an invagi- 

 nation of the epidermis, being lined by an epithelium which, over 

 the greater part of the outer hemisphere, is similar to the 

 epidermis; but the whole of the mesial surface of the wall, as 

 well as the apex and part of the outer wall, is lined by a layer of 



tall glandular cells The idea occurs to one that, in 



Phreodriloides, the spermatheca has passed forwards into segment 

 xii., and has become coincident with the male pore. But there 

 is nothing analogous to such a fusion throughout the Oligochseta, 

 and a more reasonable explanation is, that the atrium has become 

 a reservoir for the spermatozoa, and that copulation does not 

 occur and that the muscular sac (or ' autospermatheca ') discharges 

 its own spermatozoa on its own ova, during the formation of the 

 cocoon." 



The nature of the spermathecse, with their ducts devoid of any 

 direct communication with the exterior through spermathecal 

 pores, and entering into connection with the ovisac-structures, 

 would seem to render more possible the moving forwards of the 

 spermathecal structures; or, at all events, to argue that the 

 spermatheca^, as such, have really disappeared in Phreodriloides 

 and an " autospermatheca " developed. In Astacopsidrilus 

 fusiformis, the spermathecal ducts are exceedingly fine tubes; 

 and the musculature, readily noticeable as a constituent of the 

 wall of the same ducts in A. notabilis, is practically absent. 

 Traces of what evidently was a spermathecal pore, comparable 

 with those of species of Phreodrilus, were noted in sections of 



