422 PROF. F. J. BELL ON THE ECHINOMETRID^. [Mar. 1 5, 



ECHINOMETRA LUCUNTER (Lamk.). 



Questions of identifications of species are in some cases inter- 

 minable ; and we seem here to have an example of one in which 

 there would be found much to say on both sides, were it worth the 

 while, and were questions of synonymy the end of zoological science. 

 I shall not, I imagine, be accused of any blind following of Prof. 

 Alex. Agassiz ; but I follow him in this case for what, I submit, is a 

 sufficient reason. The labels of Linnseus's specimen of E. lucunter 

 are lost ; Leske found it difficult to decide to what figure of Klein's 

 Linnaeus meant to refer : Lamarck's typical specimens are in exist- 

 ence. The reviser of the group having to settle what species he would 

 call E. lucunter, came to the conclusion that he would follow Lamarck. 

 Whether the present writer would have done the same, had he been 

 the reviser, need not be discussed ; it is certain that had Prof. Loven 

 or Dr. Liitkeu been the revisers, they would have adopted a different 

 course {cf. Agassiz, op. cit. p. 284). But a decision has been given ; 

 it is almost certain that no further light will ever be thrown on the 

 difficulty; the 'Revision of the Echini' is our present standard. 

 Let us, then, when we cannot oppose facts to facts, but only opinions 

 to opinions, follow the Reviser, and let the question (and all such 

 questions) drop. 



Large forms of this species differ so much in appearance from 

 smaller specimens, that, where the series fails, one is at once almost 

 inclined to imagine that one has to do with a distinct species. One 

 specimen in the national collection (which has its longest axis 79 

 and its morphological axis 76 millim. long) is greatly bowed on its 

 actinal surface, and has the smaller tubercles exceedingly well deve- 

 loped ; there is a large number of very small anal plates ; here and 

 there five pairs of pores are found in an arc. But the most striking 

 variation, and one which, in our present state of information, we 

 should almost be justified in taking as a basis for the formation of a 

 distinct variety, represented by this form, lies in the characters of 

 the auricular arch : there is a considerable development in the 

 amount of calcareous matter there laid down ; the arch is conse- 

 quently very strong, the foramen very small, the top piece is well 

 developed, and the connecting ridge, instead of being low, is nearly 

 half the height of the whole arch. 



The plates on the buccal membrane are very large ; and the ends 

 of the radii in the lantern of Aristotle are well developed. 



On the other hand, the characters of the auricular arch are not 

 very constant in this species ; and the proportions of the parts of 

 the specimen in question are not at all unlike those of a specimen 

 76 millim. in diameter, the measurements of which are given in the 

 ' Revision of the Echini ; ' so that better service is done by directing 

 attention to its peculiarities than by imposing a new name on this 

 already heavily weighted species. 



Two specimens, purchased in 1844 from Mr. Gould, bear the 

 locality of " Abrolhos." I am unable to distinguish them from other 

 specimens of E. lucunter ; and I can hardly suggest that the locality 

 given in the Register is altogether wrong ; for one specimen, at any 



