392 KCMINODERMATA. 



sides, rather than that of a star. The radiation is only marked ex- 

 ternally by the groove of the feet *. 



In others there is a slight re-entering angle in each side of the 

 pentagon f. 



The sides of some are concave, which approximates them to a stel- 

 lated figure J. 



In these various species the caeca and the ovaries are not so elon- 

 gated as in most of those which have their rays elongated and sepa- 

 rated by strongly marked re-entering angles. Such are 



A. riibens, L. ; Encyc, CXIIl, 1, 2. Extremely common on 

 the whole coast of France, so much so, that in some districts 

 they are employed to manure the soil. 



A. glacialis, L. ; Link., XXXVIII, 69; Encyc. CVII and 

 CVIII. This species is frequently more than a foot in diameter. 

 The spines which invest the superior part of its body are sur- 

 rounded by a multitude of fleshy tubes which compose a sort of 

 cushion round their base. 



A. aurantiaca, L. ; Link., VI, VII, XXfll; Encyc. CX : 

 Egypt. Echin., pi. iv, I. The largest species of the European 

 seas ; the edges of its rays are furnished with pieces arranged 

 like paving stones, on which strong and movable spines are articu- 

 lated. The whole of the superior surface is covered with little 

 spines, terminated by a truncated and bristly head §. 



Some species have more than five rays \\. Their caeca and ovaries 

 are very short. 



We should separate those species in which the rays are destitute 

 of the longitudinal groove underneath for receiving the feet ; gene- 

 rally, these rays are not hollow, and the stomach is not prolonged 

 into them in the form of caeca, but its prominences remain in their 

 intervals. Locomotion is principally effected by the curves and mo- 

 tions of the rays, and not by the feet, which are too few for that 

 purpose. 



Those, which have five non-ramous rays round a central disk, 

 form the Ophiur^ of M. Delamarck ; but we should also distinguish 



Those in which these rays are furnished on each side with movable 



* Asferias discoidea, Lam., Encyc. Method., Vers. XCVH, XCVIII ; — ^$. tesse- 

 lata, var., A, Lam.; Link., XIII, 22 ; Encyc, XCVI. 



-f- Asterias membranacea, Link., 1, 2; — A. rosacea, Lam. ; Encyc. XCIX, 2, 3. 



+ Asterias iesselata, var. C and D, Lam, ; Link., XXIII, 37, XXIV, 39 ; Encyc, 

 97 and 98,1,2; — A.equesirU. \.. and Lam.; Link., XXXIII, 53; Encyc, CI.CII; 

 — A. reticulata. Lam. ; Link., XLI, XLII ; Encyc, C, 6, 7 ; — A. mHitaris, Miill., 

 Zool. Dan., CXXXI •,—A. mimita, Seb., Ill, v, 14, 15 ; Encyc, C, 1, 3 j—A. nodosa, 

 Link., TI, III, VII ; Encyc, CV, CVI. 



§ Add A. rosea, Mull., Zool. Dan., LXVII ; A. violacea, lb., LXVI ;— .4. echi- 

 niphora, Lam. ; Link., IV, 7 ; Encyc, CXIX, 2, 3 ; — A. variolata, Lam. ; Link., VIII, 

 10 ; Encyc, Ibid., 4, 5 ■,—A. laevigata, Unk., XXVIII, 47 ; Encyc, CXX -.—A. sepo- 

 sita, Link., IX, 16 ; Encyc CXII, 1, 2. 



II Ast. paposa, Link., XVII, 28, XXXIV, 54; Encyc, CVII, 3, 4, 6, T -.—A. 

 echinifes. Lam.; Solander and Ellis, Coral., LX— LXII ; Encyc, CVII, A.—C,—A. 

 helianthiis, Lam. ; Encyc, CVIII and CIX. 



