I9I4-] J- Stephenson : Oligochaeta. 397 



however, in the depressed area between the pores, there is a 

 row of about eight setae. 



Variations in the appearance of the pits are found ; thus 

 they var}^ in depth, being occasionally quite shallow, and in 

 the amount of puckering of their sides; they maj' appear, with 

 the furrow connecting them, as a transverse groove occupying 

 a position between the setal rings of xvii and xviii. The con- 

 dition shown in fig. 16 is to be derived from that first described 

 by lengthening the posterior angles of the puckered pits till they 

 reach the male pores ; in the specimen there figured, the pores 

 thus come to lie at the posterior angles of a rectangular depres- 

 sion with irregular lateral walls, a smooth anterior wall, and 

 no posterior wall, i.e. the depression here shades off into the 

 concave ventral surface of the body. It will be seen from the 

 figure that the pores are well behind the setae in the floor of 

 the depression. 



The female pores appear to be paired, close together (separa- 

 ted only by an interval less than 2aa) and just behind groove tJ. 



The spermathecal apertures are prominent, round, and late- 

 rally placed, near the margins of the flattened ventral surface. 

 They are three pairs, in furrows -f, i and f . Most of the aper- 

 tures in the various specimens are occupied by a yellow glutinous 

 mass, which projects from them. 



The first septum is f. The extremely rudimentary'' gizzard 

 is in front of this, i.e. in segment v; it manifests itself as a 

 slightly wider portion of the oesophagus, but its walls are quite 

 soft and not thickened. There are no calcareous glands. 



The last hearts are in segment xiii. 



The nephridia form a regular line on each side. 



Testes were not seen ; there are two pairs of funnels, in seg- 

 ments X and xi, free, large and markedly iridescent, and much 

 elongated transversely 



In one of the two specimens dissected (from Rotung) the 

 vesiculae seminal es were a single pair onl}^ in segment xii, 

 attached to the posterior face of septum H ; they were small, 

 lobulated, and dorsally placed, abutting on the dorsal vessel 

 and on each other in the middle line. In the other (from the 

 batch of four from Renging) there were two pairs, in segments 

 xi and xii, on septa }'} and H respectively ; those in xi were 

 small, and flattened on the septum, those in xii were larger; 

 the appearance of both pairs was peculiar^ — they were glancing 

 and iridescent like the funnels, and the lobules of which they 

 were composed were small, close-set and hemispherical, so that 

 the surface might be described as mammillated, or better shot- 

 like or beady. 



The prostates vary in size, occupying segments xvii-xx 

 (right side of Rotung specimen), xviii-xx (left side of same), 

 xvii~xix (Renging specimen). Ivach forms a compact firm mass 

 of large size, bulging forwards or backwards the limiting septa ; 

 the surface is slightly indented into lobes. The duct is stout 



