476 H. F. MOORE. [Vol. X. 



material. The protoplasmic basal portions of these gland cells 

 are prolonged into fine filaments, which join one another to 

 form the partitions between the columns of cells, and finally 

 ramify in the circular muscle-layer. Each of these cells, at its 

 base, contains a nucleus and nucleolus. 



The deficiency in the depth of the ventral portion of the 

 clitellum is in the deeper layers of cells; otherwise, this por- 

 tion is similar to the dorsal. The cells described are similar to 

 those figured for Lumbricus by Cerfontaine (6), except that in 

 the present species the cells of the deeper layer are more 

 robust, and the arrangement more irregular. 



This is the only region in which my preparations show the 

 blood capillaries passing directly into the hypodermal layer. 



In the first two somites the longitudinal muscles are de- 

 flected from the body-wall, and are attached to the buccal 

 chamber in such a manner as to serve as retractors of that por- 

 tion of the alimentary canal. 



The longitudinal layer of muscles is thicker ventrally than 

 dorsally, and is somewhat interrupted in the line of insertion 

 of the setae. It has the usual bipinnate arrangement, blood- 

 vessels and nerves running in the "rachis." The circular 

 muscle-layer is of uniform thickness on all aspects of the body. 

 Many of the fibres in both layers are tubular, or solid with a 

 clear axial portion, and lie imbedded in a large quantity of con- 

 nective tissue. 



The dorsal and ventral pairs of setae are usually connected 

 by muscular slips passing, on each side, internal to the longi- 

 tudinal muscle-layer, and just beneath the coelomic lining. 



There are also oblique fibres subtending a portion of the 

 ventro-lateral region, between somite XVI and the clitellum. 

 When these contract they flatten the ventral surface and pro- 

 duce a well-marked ventro-lateral ridge, extending from the 

 genital region to the clitellum. These oblique fibres run 

 between the fibres of the longitudinal system, and are similar 

 to the "arciform" muscles which Cerfontaine (6) has figured 

 in Lumbricus. 



None of the setae in the region of the genital apertures are 

 modified, but in connection with certain of the follicles, or 



