Z. ASCID10IDA. 
259 
tinued below the edge of the tunic, and the current produced in the 
water, and the food it brought, flowed into a cavity there, at the bot- 
tom of which was active indistinct motion as if of filaments. A con- 
nexion was thought to exist between that part and the place where 
the revolution was going on, but no act of deglutition was per- 
ceived. 
“ No current of blood was visible in the stem, nor any circulation 
either in the body or the arms. Much of the space within the tu- 
nic was occupied by a darkish appearance, the nature of which was not 
ascertained. I had not opportunity to inspect other individuals, but 
the species seemed to be intermediate between such animals of Flus- 
tra as I had met with, and the pedunculated compound Ascidia ; 
more nearly related to the former, but approaching the latter in the 
form of the lower part of the body, the position of the rectum, and 
the absence of all apparent effort of swallowing : and if with the help 
of imagination we could connect the ciliated arms together by cross 
bands at intervals and unite their ends in a circle, extending the tu- 
nic to meet that circle, and leaving an opening for the funnel where 
the rectum is placed, the organ would not be unlike the branchiae of 
some Ascidiae. Indeed the affinity appeared to me not very distant 
between Ascidia and Flustra ; while, to the Sertulariae, except in the 
resemblance given by their projecting arms, I can discover no more 
analogy in the Flustrae than in the Ascidiae themselves.” Lister , 
