DRKPANOMEMA \AMPYRELLA. 81 



owing to inniimerablo muscles it was not possible to determine this conclusively. 

 Neither was it possil)le on this accoimt to determine if any subradular system 

 exists. 



The relations of the pedal and lateral ganglia call for few special remarks. 

 In some places it was possible to demonstrate pedal commissures, and to trace 

 connectives between the jiedal and lateral cords, especially in the hinder regions 

 of the animal where the cords are closer together. The most posterior connective 

 is especially heavy (Plate 11, fig. 1), and develops two or three fibres whose 

 branches may be traced to the musculature of the body wall. On the inside a 

 very few exceedingly delicate nerves pass to the terminal section of the coelomo- 

 ducts. From the posterior swollen section of the lateral cords {ganglion superior 

 posticus) several nerves arise chiefly distributed to the body wall. The dorsal 

 commissure is relatively' heavy and closely applied to the dorsal wall of the 

 rectum. In the median line it gives rise to a nerve that may be traced to a 

 point near the dorso-terminal jjortion of the body. In position it corresponds 

 to the nerve supph'ing the dorsal sense organ in other Solenogastres described 

 in this paper, but no such well-defined sensor}* area appears to be present in this 

 species. 



In this species the paired gonad, without any special peculiarities, terminates 

 rather abruptly at a point about as far forward as the hinder border of the atrial 

 opening, and on the other hand passes by two relatively large ducts into the 

 spacious pericardial chamber (Plate 11, fig. 1). From the lateral portions of a 

 small recess at the posterior end of this cavity each coelomoduct arises, and after 

 pa.s.sing downward for a short distance then passes forward, gradually increasing 

 in size until it reaches a position about level with the hinder tip of the gonad. 

 Here it bends abruptly and coursing backwaid unites with the one of the opposite 

 side, and as a short common duct makes its waj' to the cloaca. 



Each canal commences its course with an epithelial lining essentially like 

 that of the pericardial wall, being composed of low flat cells entirely devoid of 

 cilia and lateral cell boundaries. These deficiencies are soon overcome, however, 

 and there are evidences in some of the cells a short distance from the pericardium 

 of a slight glandular activity. In proportion to the increasing diameter of the 

 duct the cells show a greater width and height and the cilia become a strongly 

 marked feature. This holds true for only a portion of the canal however for 

 at a point slightly below the level of the lateral nerve the character of the lining 

 changes abruptly. At this point the cells become high and columnar along the 

 dorsal side of the tube and form a ridge, extending forward to the most anterior 



