410 PROF. F. JEFFREY BELL OX THE [May 1, 



concerned Ophiocrene seems to show that some ancestor of this 

 group was provided with distinct radial shields, the presence or 

 absence of which is so variable a character in the Streptophiurae, 

 which I have, I think, shown to be ancestral to the Cladophiurse. 



Ophiocrene '. 



An Ophiuroid with branching arms and the habit of an Astro- 

 phytid, but with ealycinal plates on the disc, and rounded radial 

 shields of comparatively small size. 



Ophiocrene jEnigma, sp. nov. (Plate XXVII. figs. 1-5.) 



As there is only one specimen, and that small, it is impossible to 

 say whether or no it is adult. It may be provisionally defined 

 thus : — Small, with delicate arms and few branches, of a milky- 

 white colour, the joints separated by fine brown lines. 



Macclesfield Bank, 45 fms. 



It may be pointed out that, at present, there is no evidence that 

 would justify us in regarding this as the young of some already 

 known Astrophytid of large size, but it is quite within the bounds 

 of possibility that a series of stages may show it to be so. 



V. ECHINOIDEA. 



Temnopleurus bothryoides. 



Pleurechinus bothryoides, A. Agass. Chall. Eep. Ech. iii. p. 108 

 (1881). 



Temnopleurus bothryoides, Bell, Rep. Voy. 'Alert ' (1884) p. 119. 



It is quite clear that this is by no means a rare species ; the 

 ' Challenger ' and the ' Alert ' both brought home examples, and 

 the ' Egeria ' took it in at least four dredgings between 40 and 47 

 fathoms. In the smallest specimen, which is not 4 mm. in 

 diameter, the deep and extensive pitting characteristic of the 

 species is quite well marked. 



I have a pretty strong conviction that the progress of research 

 will result in showing that Pleurechinus variabilis and P. ruber of 

 Dr. Doderlein are synonyms of this variable species. 



Temnopleurus reynaudi. 



Temnopleurus reynaudi, Agass. 



An examination of two specimens covered with spines confirms 

 me in the view I expressed in 1880 2 that T. reynaudi and T. granu- 

 losus are distinct species. The examples now before me are some- 

 what larger than the spined specimens collected by H.M.S. 

 1 Challenger ; ' the spines are rather long, creamy white, with bands 

 of red, or with the free end red. 



1 As the word Egeria has been several times used in Zoology, and as Kpi)vr} 

 means a fountain, and Egeria was, it is said, changed into a fountain by Diana, 

 I have, in this roundabout fashion, succeeded in associating H.M.S. ' Egeria' 

 with this interesting genus. 



3 P. Z. S. 1880, p. 424. 



