The Morphology of a Solenogastre. 719 
of the body but are separated by such a wide interval that it has 
been possible to trace commissures in only a few places. Latero- 
pedal connectives on the other hand have been found to exist with 
considerable regularity from one end of the body to the other. The 
position of the lateral cords is accurately shown in Figs. 7, 8 and 
requires no farther comment. 
After separating from the pallio-pedal connectives the labio-buccal 
cords pass backward imbedded in the thin muscular sheath of the 
digestive tract and unite with the labio-buccal ganglia (Fig. 7). These 
are relatively large elongated bodies superficially placed in the depression 
separating the salivary gland from the pharynx proper. From the 
anterior end of each a commissure originates and passes over the 
dorsal wall of the digestive tract immediately in front of the salivary 
glands. This nerve corresponds to the dorsal commissure that I have 
found in Rhopalomenia scandens and Proneomenia hawatiensis and is 
probably the homolog of the dorsal buccal commissure in the chitons. 
From the hinder end of each ganglion the inferior commissure arises 
and passes backward beneath the digestive tube and above the 
radula a short distance posterior to the level of the salivary glands. 
In close proximity to the origin of this latter nerve a delicate fibre 
arises from each buccal ganglion and courses backward on the dorsal 
side of the oesophagus close to the mid line. Several small ganglia 
occur along its course and there are indications that minute nerves 
arise therefrom but whether these form a plexus as they are known 
to do in the pteropod, Corolla spectabilis for example, it is not possible 
to determine from sections. 
The subradular commissure, devoid of any well defined ganglia 
so far as I am able to determine, forms an extensive loop encircling 
the forward pharyngeal wall in the neighborhood of the subradular 
organ described on page 706. As Fig. 7 shows this cord is attached 
to the forward end of the labio-buccal ganglia as in Proneomenia 
hawanensis and Rhopalomenia scandens (see page 727). I have not been 
able to find any labial commissure passing beneath the radula in 
the usual fashion. In Rhopalomenia it is relatively short but here, 
if it exist at all and passes beneath the radula, its length must be 
relatively great. 
Posteriorly the pedal and lateral cords gradually approach each 
other and finally unite in a well defined ganglionic enlargement 
(ganglion post. inf.) at the base of the cloacal cavity (Figs. 8, 18). 
From this point a relatively small commissure passes upward against 
