78 DREPANOMENIA VAMPYRELLA. 



The body (Plate 2, fig. 2) measured 9 mm. in length, was slightly compressed 

 laterally, })articularly its anterior half, and in form was somewhat spindle shaped, 

 being largest about the middle section of the body and gradually tapering off 

 toward each end, especially posteriorly where the body becomes quite slender 

 before terminating in a truncated extremity. A well-defined keel extends along 

 the entire animal in the mid dorsal line. The color was faint j^ellowish white. 



The cuticle surrounding the body is of medium thickness, measuring 0.35 

 mm. in the keel and 0.28 mm. elsewhere in the dorsal region, but gradually 

 decreasing to half this amount on the ventral surface. It includes a single 

 layer of radially directed spicules (Plate 32, fig. 6), ranging in size from those 

 in the first stages of formation to others of the keel 0.129 mm. long. All are of 

 the same general form represented in Plate 37, fig. 7. It is to be noted that 

 many of the spicules are not in contact with the hypodermis, even the matrix 

 cells having disappeared, but are situated far out toward the surface of the 

 body. Beneath each developing spine are several cells apparently instrumental 

 in its formation. 



The cells of the hypodermis are very small and indistinct and accordingly 

 have been examined only superficially. The prevailing cells are slender with 

 sul)central nuclei, and are developed into numerous small elevations, some of 

 which connect by strands with the overlying papillae (Plate 32, fig. G). These 

 last named organs contain upwaiils of eight cells in the enlarged portion; none 

 appear to exist in the exceedingly slender stalk. 



As in other species of the family the ventral furrow commences close to the 

 hinder border of the lip, and extending the entire length of the animal becomes 

 continuous with the cloacal opening. Anteriorly it contains a relatively deep 

 excavation into which the anterior pedal gland opens by the usual numerous 

 intercellular ducts. This last named gland occupies jjractically all of the vis- 

 ceral cavity between the region of the brain and tlie anterior end of the gonad. 

 The cells comjiosing it are generally pyriform, with an average diameter of 

 .021 mm. and are filled, save for the small compact nuclei, with a finely granular 

 substance that stains intensely with logwood dyes. In some cases this secretion 

 api^ears to be undergoing solution, and presents a vacuolated appearance, a 

 character that is very pronounced among the cells of the posterior pedal gland. 

 Tliese latter elements are related also to the foregoing in general form, size, and 

 appearance, and extending to the cloaca and opening on each side of the foot, 

 are thus seen to hokl the usual position. 



At the hinder Ijorder of the crypt into which the anterior pedal gland opens, 



