of Simple Ascidians. — 367 
. We have seen only one specimen of this well-characterized 
species. It was adhering to the inside of a dead shell of 
atella vulgata dredged in Guernsey by Mr. Jeffreys and the 
Rev. A. M. Norman in 1865. 
The depressed form and large surface of attachment in this 
little Molgula are characters very unusual in this genus. An- 
other peculiarity is observed in the reversed position of the 
oviduets. 
Genus EUGYRA, Alder & Hancock, MS. 
the genus as above. Since then, another "eee of Hugyra 
has been discovered, and has now to be recorded. 
double spiral coils rather stout. Intestine forming a single 
So short and constricted towards the anal extremity, and 
widening at its junction with the stomach. - Liver bulky, of a 
black olive-green. Reproductive organs of a pale yellow, 
placed partly within the intestinal loop, and partly above it. 
iameter half an inch. ; : 
A single specimen of this interesting species was dredged 
by Mr. j effreys and the Rev. A. M. Norman in Guernsey in 
1865. E. sis is distinguished from J£, arenosa by the 
