234 Freda Bage : 



small size of the nephridiopores, by a fine duct, passing from 

 the vesicle, through the longitudinal and circular muscles, to the 

 exterior, and opening near the anterior border of each segment. 

 The cells of the epidermis are turned in at the opening, lining 

 it for a short distance. I can find no trace of special muscles, 

 as in Woodtvardia rooraniensis, which could control the open- 

 ing to the exterior. In this form, also, the vesicle [Fig. 17] 

 has no caecum, the opening to the exterior being at the end of 

 the bladder, awav from the nerve cord. 



9. — Woodwapdia cooraniensis,^ Spencer; 



syii. Cryptodrilus cooraniensis, Spencer (17). 



Xephridiopores clearly marked. Though the openings in the 

 many specimens vary somewhat in position in regard to the 

 setae in the hrst live or six segments, they agree in being 

 alternate down the rest of the body. The general arrangement 

 seems to be that shown in the figure [Fig. 18], Spencer (17). 

 The first three nephridia in segments 2, 3 and 4, open opposite 

 the fourth seta, fourth, fifth and sixth opposite the third seta, 

 seventh opposite fourth, eighth opposite second, and the rest 

 alternating in position opposite fourth and second setae. 



The nephridial system is meganephric. 



Macrosnjjyir Structure. — One pair of meganephridia is pre- 

 sent in each segment after the first, and there are no micro- or 

 pepto-nephridia. The most -noticeable feature in the arrange- 

 ment of the nephridia in the body is the alternation in the 

 arrangement of the various parts of the nephridia to corres- 

 pond with the alternation in position of the external openings. 

 The nephridia are arranged in two distinct sets, the vesicle, 

 which is of large size, being conspicuously placed towards 

 ventral [Fig. 19, A.] or dorsal [Fig. 19, B.] line, as the nephri- 

 diopores open opposite the second oi- fourth seta respectively. 

 Very little more than the general arrangement of the neph- 

 ridia could be seen by dissection, and the position of the 

 funnels, which are extremely small, could not be determined. 



1 .Mi<liaflsfii, il.id. 



