DESCRIPTIONS OF GENERA AND SPECIES 467 



important points of unlikeness from Microscolex. The present species is without 

 egg-sacs and gizzard. The most remarkable characteristic is said by EISEN to be the 

 spermatheca, which is sometimes a median unpaired structure and sometimes paired ; 

 it has, too, excessively thin walls. There are septal glands in segments vi-ix ; in 

 vi-viii or v-viii in the two following species. These structures do not seem to 

 occur in other species of the genus. This and the two following species are more 

 fully described by EISEN in (16). 



(17.) Microscolex troyeri (EISEN). 



Deltania Troyeri, EISEN, loc. cit., p. 251. 



Definition. Length, 30 mm. Prostomium incomplete ; no dorsal pores. Clitellum, XIII-XVII. 

 Setae in eight rows, ventral converging on genital segment. No gizzard. Spermathecae 

 with paired diverticula. Sperm-ducts open into spermiducal glands within body-wall. 

 Penial setae not ornamented. Hab. Golden Gate Park, San Francisco. 



(18) Microscolex benhami (EISEN). 

 Deltania Benhami, EISEN, loc. cit., p. 252. 



Definition. Length, 25 mm. Prostomium incomplete; no dorsal pores. Testes in X, XL 

 Clitellum, XIII XVII. Setae in eight rmvs, ventral converging on genital segments. 

 No gizzard. Spermathecae in IX, with two small diverticula. Spermiducal glands open 

 into spermiducal gland within body-wall. Penial setae not ornamented. Hab. Alameda 

 county, California. 



(19) Microscolex monticola (NEW SPECIES). 



Definition. Length, 31 mm. ; diameter, 3 mm. ; number of segments, 79. Setae paired, 

 dorsal wider apart than ventral. Prostomium complete. Dorsal pores present. Gizzard 

 in VIII (?). Testes in X, XL Sperm-sacs in XII. Spermathecae in IX, with two 

 diverticula. Spermiducal glands long and coiled. Penial setae (?). Hab. Mount 

 Pirongea, Auckland, New Zealand. 



In alcohol the single example of this species, which I owe to the kindness of 

 Capt. Brown, was almost black in colour, the setae being implanted upon a white 

 ground. There was no clitellum. 



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