282 AETHUR E. SHIPLEY. 



remarks that one inight tliink that the two authors were 

 observing different species. Francois suggests the specific 

 name echinorum. 



The auimal is again recorded in 1892-8 by L. Cuenot,i 

 who draws attention to the fact that it corresponds well with 

 the character of the family Vorticida of von Graff, and 

 indeed to his sub-family Vorticina Parasitica, wliich 

 includes another parasitic genus of Turbellaiia, Anoplodium, 

 also found in echinoderms. Silliman, Francois, and Cuenot 

 all promise full accounts with figures of the anatomy, but as 

 far as I can find out these have not yet appeared. 



Last autumn my friend Mr. W. F. Cooper brought me 

 eleven specimens of this parasite which he had found, ten 

 in the alimentary canal, and one lying on the genital gland 

 in the perivisceral cavity of a specimen of Echinus escu- 

 lentus, L., that he was dissecting at the Marine Biological 

 Laboratory at Plymouth. This winter I have worked out the 

 anatomy of the form and made numerous drawings. After 

 I had completed the work I discovered that Professor 

 Russo ^ had been over very much the same ground ; he has, 

 I believe, anticipated me in many details, but as the parasite 

 is very interesting, and is now recorded from the British 

 area, and as the periodical in which Professor Rosso's full 

 paper appears is very inaccessible — I have not been able to 

 find a copy in any of our libraries — I have thought it not 

 useless to publish the following general account of the 

 anatomy of Syndesmus echinorum, Fran^. 



Anatomy: External Features. — The eleven specimens 

 vary from 1 mm. to 2 mm. in length, and their greatest 

 breadth is one half of their length. These dimensions are 

 considerably less than those recorded by Fran9ois. His 

 specimens were nearly twice this size. In shape the animals 

 are leaf -like, and have a tendency to be hollowed out ventrally. 

 The anterior end is more rounded than the posterior, but in 



• ' Rev. biol. Noni France,' v, 1892-3, p. ]. 



2 ' Kic. Labor, anat. Roma,' v, 1895, abstracted in 'Monit. Zool. ital.,' vii, 

 1890, p. 6. 



