Z. ASCIDIOIDA. 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 j)art 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 Ascidise. 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 Ascidise themselves." Lister. 



