74 



meeting of the British Association; but concerning which 

 the only conclusion definitely formed was, that the species, 

 and perhaps the genus, was new to Britain, if not to science, 

 It consisted of an oblong mass ten inches in length, seven 

 wide, and about three in thickness, the weight three ounces 

 less than three pounds. The under surface, by a portion of 

 which it had been attached to a solid body, was flat and 

 bare, and of the whole breadth of the animal; but it was not 

 quite the whole length. At the end which I would designate 

 the anterior, was a wide and somewhat deep cavity, but not 

 leading to any organization within ; and it is at this part that 

 the flat under surface does not quite reach the extremity. At 

 the left side (counting the anterior end as front) a void space 

 for two thirds of the length, bare and rigid, and on its upper 

 portion an orifice; another in a depression about the middle 

 of the upper surface; the direction running toward one side. 

 Round the margin of the under surface, and irregularly 

 placed on the upper, are a number of lumps or broad tuber- 

 cles, which are covered and encircled with flaccid processes, 

 that are most numerous on the anterior end. They vary in 

 length from a quarter of an inch to an inch, and a few are 

 bifurcate. If there be any orifice to these processes, it is 

 minute; but the process is wide, flat, aud flaccid; and each, 

 has a light coloured vessel, or intestine having yellow or 

 brown contents; and a row of white thick set dots on each, 

 side. Colour a leek-green, except the processes, which 

 therefore appear conspicuous. This description conveys the 

 idea of an animal of the class Ascidia, and differing from the 

 ordinary form of the known species only in the existence of 

 organized processes, But dissection proves it to belong to 

 a very different genus of the Cuvierian order Acalepha, 

 Instead of having a separate intestine communicating with 

 orifices, the whole of the interior was solid, gelatinous, and 

 only not homogenous by being intersected in all directions 

 with a multitude of fine white threads, Beside the protru- 

 ding processes, a tew also were found inserted in the sub- 

 stance beneath the surface, as if not yet exserted. Each of 

 these processes contains a stomach or intestine, which pene-» 

 trates for nearly an inch, swelling as it approaches its 

 greatest depth ; and from this part a thread passes into the 

 anterior, anastomosing with others in an inextricable net- 

 work : at last uniting again to form two black threads, one 

 of which passes to each of the orifices already mentioned, 

 jn the side and summit. In each of these orifices was a 

 quantity of powdered coralline; but no grittiness could be 

 perceived in any other part of its structure. It seems 

 therefore to become digested in the cavity, and the nutritive 

 part only to be conveyed within. In one part of the interior 



