1914-] J- Stephenson : Oligochaeta. 393 



behind this, Dorsally the ring is not quite complete, 2,2: = 2y^ ; 

 mid ventrally the ring may be unbroken, and the interval aa is 

 in any case very small. The setae are closer together ventrally, 

 the distances increasing towards the lateral margin ; dorsally the 

 intervals are about twice as large as on the ventral surface. In 

 number they were counted as ix/63, xx/65. 



The clitellum apparently embraces segments xi--xiii=3. It 

 is indistinct dorsally, and is not visible ventrally ; the furrows 

 are not obliterated, and setae and dorsal pores are present. 



The male apertures are not far apart, on segment xviii. 

 The whole length (antero-posteriorly) of this segment is depressed 

 in the mid-ventral region, the depressed area being limited in front 

 and behind by the neighbouring segments, and laterally by con- 

 spicuous lips (fig. 13). Just internal to these lateral lips is, on 

 each side, the deepest part of the depression, and here can be 

 seen a small transverse groove, in the outer part of which is 

 situated the male aperture, distant from its fellow about rr of 

 the circumference. The setae end on the lip-like margin ; none 

 are present in the depression, and no genital setae were dis- 

 covered. 



The female aperture is indicated by a slight depression, pale 

 in colour, in the mid- ventral line on the anterior portion of 

 segment xiv, between the setal ring and the nitersegmental 

 furrow. 



The spermathecal apertures are conspicuous, in furrows f 

 and I, about ? of the circumference apart. 



The first distinguishable septum is il ; none are markedly 

 thickened. 



The gizzard is rudimentary, in segment v ; its diameter is 

 slightly greater than that of the succeeding part of the canal. 

 The oesophagus is marked by transverse vascular rings (recog- 

 nized by their dark colour) in segments viii, ix and x. The 

 intestine begins in xiv. 



The last heart is in xii. 



The excretory system is meganephric ; the terminations of 

 the nephridia are in the same longitudinal line. 



The testes were not certainly identified. The seminal funnels 

 are free, in segments x and xi. The vesiculae seminales are two 

 pairs, in segments xi and xii; they are attached to the anterior 

 septum, and appear as flocculent masses, filling up the length 

 of the segment and nearly meeting dorsally over the gut. The 

 prostate is confined to segment xviii ; it is a small lobed mass, 

 with a duct which is moderately long relatively to the size of 

 the gland, several times bent on itself, and wider towards its 

 termination. 



The ovaries are in segment xiii ; funnels were not identified. 



The spermathecae lie in segments vii and viii ; they are 

 small and of simple form, short, stumpy and rounded, with a 

 short, very broad duct, not sharply marked off from the ampulla, 

 and without diverticulum. 



