VOL. LII.] PHILOSOPHICAL TRANSACTIONS. 635 



XCIl. Of a remarkable Marine Production.* By Alexander Russell, M.D.,and 



F. R. S. p. 554. 



Extract from Dr. Nusmytlis Letter, who brought the animal from America, 

 " At my return from North America, in November 1759, I sent you 2 or 3 

 articles picked up in that country. One of these, from its singular appearance, 

 and from its being a perfect stranger to every body that saw it, I must now re- 

 commend to your attention. The desire of keeping it entire, and as it was found, 

 prevented any other investigation, than that of viewing it particularly, when I first 

 got it, and at times afterwards, to be assured of its safety, as well as to observe 

 the changes it might undergo while it continued in spirits. 



In June 17 5Q, the squadron destined against Quebec arrived in the river St. 

 Lawrence, when being in the latitude 49° 50' north, and about 10 leagues to the 

 westward of Anticosti, (an island in the mouth of the river) we sounded, and 

 struck ground in 42 fathoms ; the soundings white sand and black specks. 

 Having at the same time thrown overboard a fishing-line, the hook was found 

 strongly attached at the bottom ; and after some efforts, brought up a piece of 

 rock, into the surface of which was inserted a strong tendinous substance of a 

 light brown colour, in length about 7 inches ; it was round, and nearly of the 

 thickness of a common goose- quill ; the other end formed a sack, or bag, of the 

 size and shape of a pigeon's egg. The whole of this substance was elastic ; and 

 on pressing the bag, I plainly discovered a contained substance, and imagined that 

 it was attended with motion." 



[Thus far Dr. Nasmyth.] 

 On examination of it, by Drs. Solander and Russell, and Messrs. Collinson 

 and Ellis, it appeared to come nearest to what has been by naturalists called Pria- 

 pus ; they therefore named it Priapus pedunculo filiformi corpore ovato. The 

 body was oval, and in size between a pigeon and pullet's egg, smooth, membran- 

 ous, and of a silver ash colour. What appeared to be the mouth, was situated a 

 little below the apex, and was quadri valvular, in the form of a (+) cross. The 

 anus was on the same side, a little above the base, or insertion of the stalk, and 

 also quadrivalvular. Towards the aperture of the mouth and anus, the body felt 

 more callous. From this body issued a peduncle, or stalk, of 10 inches in length , 

 the extreme end of which was fixed to a piece of rock. This stalk was of a light 

 brown colour, about the thickness of a large hen's quill, round, hollow, rough, and 

 of a membraneous, leather-like substance. When the body was opened, the in- 

 ternal coat appeared to be composed of reticular fibres. The interior orifice of 



* This animal, which was referred by Linnaeus, in the twelfth edition of the Systema Naturae to 

 the genus Vorticella, under the name oiVorticella ovi/'era, is a speices of pedunculated Ascidia; and is 

 the Ascidia pedunculaia of the Gmelinian edition. 



4 M 2 



