440 L. Agassiz on the Echinodermata. 



companying figure, which was drawn from Mr. Woods's spe- 

 cimen, will, I trust, remove all doubts in future respecting this 

 beautiful little plant. 



Erytiir^ea diffusa. 



(§ Euerythraea, Griesb.) 



E. diffusa; caulibus ceespitosis adscendentibus inferne ramosis, ramis 



1 — 3-floi-is, foliis inferioribus approximatis elliptico-subrotundisspathu- 



latisque trinerviis, caulinis ellipticis oblongisque obtusiusculis, corolla; 



tubo sub anthesi calycem paullo superante, lobis tubum subaequantibus 



ellipticis acutiusculis. Griesb. MSS. Tab. Nostr. 



Erythrsea diffusa, Woods, in Hook. Comp. to Bot. Mag. v. ii. p. 274. — 



Cbironia maritima, Hort. Kew. Smith, in Herb, suo, apud Soc. Linn, (sed 



vix fide Woods.) — Gentiana scilloides, Linn. Suppl. p. 175. Willd. Sp. PI. 



v. i. p. 1346. Bcem. $ Sch. v. vi. p. 163. 



Hab. Azores, Francis Masson. On a piece of rougb ground, near Mor- 

 laix, in Britany, Joseph Woods, Esq. 



Descr. Glaberrima. Caulis gracilis, quadrangulus, digitalis fere ad spi- 

 thamaeam, inferne decurabens, ramosus ; rami elongati, erecti, subsimplices, 

 apice 1 — 3 flori. Folia opposita, decussata, semiunciam longa, inferiora ap- 

 proximata elliptica vel subrotundo-spathulata, superiora magis remota, ob- 

 longa, sessilia, omnia integerrima, obtusa, nitidiuscula, trinervia. Flores 

 terminales, solitarii, bini vel terni, majusculi, pulcberrime rosei ; siccitate 

 saepe fusco-lutei. Calyx basi bibracteatus vel nudus, raro unibracteatus, 

 gracilis, 5-fidus, subangulatus, laciniis subulatis erectis tubum aequantibus. 

 Corolla bypocrateriformis. Tubus gracilis, superne angustior, ante antbesin 

 calycem vix excedente, sub anthesi calyce £ longior, limbo 4-partito, seg- 

 mentis ellipticis patentibus, acutiusculis. Antherce exsertse, oblongse, flavae, 

 spiraliter tortae. Stylus longitudine staminum. Stigma crassum, bilobum. 



XLIX. — Prodromus of a Monograph of the Radiata and 

 Echinodermata. By Louis Agassiz, D.M.* 



[Continued from p. 307.] 

 III. 

 The Stellerides constitute the last order of the class of Echinoder- 

 mata. Their starlike form, the mobility of their rays, which are fre- 

 quently manifoldly subdivided, the position of the mouth at the centre 

 of the inferior surface, are the most prominent external characters of 

 this division, in which we must admit three families ; the Asteria, 

 the Ophiurce, and the Crino'idea. With respect to their organization 

 Ehrenberg has recently made the interesting discovery that Astcrias 



* Translated from the Annales des Sciences Naturelles for May 1837. 



