from the Channel Islands. 517 



species. As the specimen which belongs to the Greenock 

 Museum had been purchased of Messrs. Siuel and Co., of Jersey, 

 I entered into communication with those gentlemen, from whom 

 I had already received valuable specimens of worms, and was 

 able to obtain a specimen of Echinocardium covered with 

 spines, and, at first, recalling E.Jlavescens ; still later Messrs. 

 Sinel have sent me a third specimen devoid of spines, which 

 is larger than the others and deserves description. 



No anterior ambulacral groove ; test irregularly cordiform, 

 at its widest the measurement is nearly as great as the length ; 

 anterior lateral ambulacra with eight and fifteen pores, the 

 posterior with fourteen and twelve. Anus a little overhung 

 by posterior interarabulacrum ; the granules in the anterior 

 ambulacrum larger and much less closely packed than else- 

 where on the dorsal surface of the disk. 



Greatest length 74 millim., greatest width 71 millira. 



A comparison of this description with that given by Mr. L. 

 Barrett of what, with doubt, he calls Amplddotus gibhosus^ 

 Agass., shows that the specimens agreed in so far that his was 

 as broad as long, had eight and fourteen pairs of pores in the 

 anterior lateral ambulacrum, had the anus depressed, and the 

 anterior ambulacrum flush with the surface of the test. 



If the ^' Greenock " and our specimen be of the same species 

 as Barrett's example, there is a further agreement in the 

 thick coating with curved spines, and the spines of the post- 

 oral space having slightly flattened tips. 



On the whole I should be inclined to think that the three 

 specimens now before me were of the same species as that 

 seen by Mr. Barrett, were it not for the following considera- 

 tions : — Mr. Alder and the Rev. Canon Norman agree in 

 thinking that the specimen assigned by Barrett to Agassiz's 

 species agrees rather with the Echinocardium pennatijidum of 

 Dr. Norman ; but this last has peculiar pedicellariae of which 

 I can find no trace, has but four pairs of pores in the anterior 

 of the antero-lateral rows of ambulacral pores, and is not 

 nearly so broad as long, having a greatest length of 60 and 

 a greatest breadth of 50 millim. 



The examination which I have been able to make o1 Echino- 

 cardium cordatum and E.Jlavescens have sliown me that there 

 is a considerable area of variability within this genus j but I 

 cannot determine its range for E. ijennatijidum or this appa- 

 rently different species without material far larger than that 

 which has already come to my hands. I shall be glad of any 

 assistance which my fellow naturalists or those who are inter- 

 ested in British zoology are able to give me. 



Zoological Department, British Museum, 



