Spengelomenia. 471 
become attached to the somatie muscles and in a few cases have 
been followed to the under surface of the hypodermis. A nerve 
from the anterior end of each ventral ganglion is likewise distri- 
buted to the ventral body wall but somewhat behind the one just 
described. 
The labio-buccal connectives arise from the postero-ventral sur- 
face of the brain, and passing backward rest upon the pharyngeal 
glands. In this position they may be followed readily, but in the 
neighborhood of the ducts of the large, ventral salivary glands they 
disappear completely. In the neighborhood of the radula they once 
more come to view, and may be followed to the labio-buccal ganglia 
beneath the end of the radula sac. Before reaching these ganglia 
each connective becomes enlarged considerably and originates a 
nerve that in other species forms a dorsal connective, but in the 
present case such branches become very soon lost to sieht among 
the numerous glands in the vieinity. 
In the posterior end of the body the lateral and pedal cords 
continue to hold the usual positions, and here and there may be 
seen to be united by commissures and connectives. ÖOpposite the 
posterior end of the pericardium the lateral ganglia expand some- 
what and are united by a strong supra-rectal commissure. Posterior 
to this point they continue some distance and give rise to a few 
branches that appear to innervate the hypodermis and somatic mus- 
ceulature. As may be seen in Fig. 12 Pl. 24 the last two con- 
nectives uniting the ventral ganglia are relativly thick, and the 
same is true of the two most posterior commissures joining the 
ventral cords. These last named ganglia originate three or four 
large nerves that pass into the muscles composing the papilla sup- 
porting the reproductive opening, but they disappear almost im- 
mediately without giving any clue to their destination. 
No dorso-terminal sense organ has been found to exist. 
Concerning the relationships of this animal there is little to be 
said as it is not intimately related to any other known species. It 
readily comes within the family Prwvotinüidae, but here for the most 
part the problem of its more accurate systematic position must rest 
for the present. In a distant way there is a resemblance to the 
senus Alexandromenia. The radula is monoserial, and there are three 
sets of salivary glands, the most conspieuous, probably corresponding 
to the ventral in other molluses, consisting of conspicuous lobules 
united to a long duct opening at the sides of the pharynx. The 
