NEOMENIA VERRILLI. 207 



the external opening of the anterior pedal gland. Anteriorly this last named 

 space appears as a narrow slit, when viewed from the mid line, but in cross 

 section it is seen to extend far outward on each side and to possess plain though 

 highly glandular walls. About midway its dorsal wall loses its glandular char- 

 acter and develops numerous folds, large and small, which more posteriorly 

 decrease to seven or eight. In the middle of the body the foot has been cut 

 away, but in the posterior third it reappears with this reduced number of folds. 

 Whether this condition continues to the cloacal chamber cannot be determined 

 owing to slight mutilations. 



As noted previously the anterior, plain-walled section of the anterior pedal 

 gland outlet is composed of highly glandular cells whose secretion, after treat- 

 ment with Delafield's haematoxyUn, stains a uniform lavendar tint. With 

 the appearance of the folds on its dorsal surface the component cells lose their 

 glandular character, and the deeper seated cells, pyriform in shape and opening 

 by delicate ductules through the folds, stain intensely and probably represent 

 the anterior pedal gland of other neomenians. Posterior to the anterior pedal 

 gland outlet these last named glandular elements decrease in size and number 

 and shade into the posterior pedal gland. 



The extremities of the body presented almost identically the same appear- 

 ance, and it was only from the study of sections that the atrial opening was 

 definitely located. The cirrose cavity into which it leads is relatively small, 

 and is almost completely separated into two subdivisions crowded on each 

 side of the body against the body wall (Plate 4, fig. 7). While there are no 

 clearly differentiated sensory ridges bounding the cirrose area, the entire atrial 

 cavity, with the exception of the cirri themselves, is Uned with an epithelium 

 composed of high and slender cells similar to those composing the ridges in other 

 species. Appearances indicate that these cells are sensory in character, but 

 the absence of undoubted nerves renders the identification uncertain. Along 

 the inner boundary of the cirrose area is an unusually high fold that like a 

 curtain shuts off to a large extent these lateral cavities from the median space, 

 which may represent the buccal cavity. If this fold represents the inner atrial 

 ridge of other Solenogastres its cells, low in form and non-ciUated, give no indi- 

 cation of possessing any sensory function. 



At the commencement of the buccal or pharyngeal cavity, a great fold, 

 seamed with numerous minor corrugations, springs from the dorsal side, and 

 in the first part of its course almost fills the cavity. More posteriorly it becomes 

 subdivided into three or four lesser folds, that, with others which have arisen 



