514 F. W. GAMBLE AND J. H. ASHWORTH. 



side. In another specimen the first left nephridium is repre- 

 sented by a very small funnel^ but all the other nephridia are 

 complete. There is an interesting abnormality in a full- 

 grown specimen from Naples. There is on the right side, 

 in the segment posterior to the fifth or last nephridium, a 

 small funnel about one millimetre long (fig, 54). It consists 

 of a well-marked dorsal lip traversed by a large blood- 

 vessel, and bearing six stout, club-shaped, ciliated vascular 

 processes. The ventral lip of the funnel is small and feebly 

 marked. 



A. ecaudata. — There are thirteen pairs of nephridia open- 

 ing on the fifth to the seventeenth chsetigerous annuli. 

 They resemble those of A. Grubii except that the funnel is 

 often a little narrower from side to side, and that the 

 dorsal lip bears a greater number of processes. All the 

 nephridia, except the first pair, bear gonads, which are indeed 

 the most characteristic feature of a dissection of this species 

 (see p. 455, and figs. 45, 46, 48). The nephridium of full- 

 grown specimens is 5 mm. to 7 mm. long, and the dorsal lip 

 bears from about fifteen to twenty-five processes, many of 

 which are subdivided distally ; in some specimens there 

 are five, six, or seven branches, but in most specimens only 

 two or three. The secreting portion of the nephridium is 

 usually less stout than that of A. Grubii. The bladder is 

 generally large. In mature females of this species ripe ova 

 sometimes accumulate in the vesicle of the nephridium in 

 very large numbers. In such specimens there is produced 

 on the inner side of the nephridium a thin-walled, sac-like 

 outgrowth of the vesicle, 3 mm. to 4 mm. in length, through 

 the semi-transparent walls of which the large ripe ova may 

 be seen (fig. 47). 



Although we have examined very many specimens of this 

 species we have not met with any case of reduction or loss of 

 nephridia, but Fauvel (1899) states that the number of ne- 

 phridia is only occasionally thirteen, twelve being the usual 

 number, the last pair of nephridia being absent from his 

 specimens. 



