6 Mindeskrift for J. Steenstrup. X. 



On studying Lyman's description and figures of Ophioihela tigris^) I was very much 

 struck by the resemblance of this species with Ophioteresis elegans ; in faet I was 

 unable to see how they could be distinguished. This would mean that the famous 

 OphiQteresis elegans is simply identical with Ophiothela tigris, and that its alleged 

 primitive structure rests only on insufficient examination. I then determined 

 to make all efTorts to get material for settling the whole matter. Seeing that 

 Ophioteresis has been mentioned by BELLfromseverallocalities^) and that accordingly a 

 not inconsiderable amount of material must be in the Collection of the British Museum, 

 I asked Professor Bell, if he could spare me a specimen, or only a piece of an arm 

 of a specimen, for study. To my great disappointment this could not be granted. 

 Fortunately, I learned afterwards from Professor Doderlein, that he had two 

 specimens of Ophioteresis elegans (one of them four-rayed), and these he most 

 liberally placed at my disposal. Further Professor H. Lym. Clark did me the very 

 great service to send me the cotype af Lyman's Ophiothela tigris and an isolated 

 arm of the type specimen, leaving both to my free use. I beg my two colleagucs 

 to receive my most sincere thanks for their great liberahty, whereby they 

 have enabled me to study the structure of this rather mysterious form, which has 

 played so important a role in the attempts to trace the natural relations of the 

 Ophiuroids. 



The comparison of Ophioteresis elegans with Ophiothela tigris showed at once that 

 they are at least very closely related. I do not venture to maintain their specific 

 identity, because I have found on closer examination one feature (the ventral piates), 

 which would seem to afford a specific difference. But the small amount of material at 

 my disposal renders it uncertain, whether the difference is not due to individual or 

 local variation. The question of the identity of the two forms must be left undecided, 

 and for the present Ophioteresis elegans and Ophiothela tigris must be regarded 

 as two separate, but so nearly related species*), that it is beyond question that they 

 belong to the same genus. The discussion of the question whether they should both 

 be regarded as belonging to the genus Ophiothela, or that Ophioteresis should be kept 



') Th. Ly man. Supplement to the Ophiuridæ and Astrophytidæ. lUustr. Catalogue Mus. 

 Gomp. Zool. No. VI. 1871. p. 10. PI. I. figs. 10—12. 



'■',) F. Jeffr. Bell. Report on a collection of Echinoderms from the Neighbourhood of Zan- 

 zibar. Ann. Mag. Nat. Hist. 7 Ser. XII. 1903. p. 246. ("Found nestling in the arms of a many- 

 armed Actinometra from Zanzibar"). 



F. Jeffr. Bell. Report on the Echinoderma (other than Holothurians) collected by Mr. 

 I. Stanley Gardiner in the Western Parts of the Indian Ocean. Trans. Linn. Soc. Ser. 2. Zool. 

 Vol. XIII. p. 19. (No remarks, but it appears to have been found in three or four different local- 

 ities, in 20 — 40 fms.). 



In the paper quoted, where the species is described, Bell says that there were "some ex- 

 amples" of it (Op. cit. p. 178). 



») See Additional Note ; p. 16. 



