136 DR. J. E. GRAY ON PLATASTERIAS. [Feb. 7, 



cou et du thorax, qui n'exisle pas dans l'ancienne espece dont le 

 peu de roux qui se trouve melange au cou et a la poitrine est 

 toujours d'une paleur qui ne rapproche en rien de la vivacite de celle 

 de notre nouvel oiseau ; et il en est de meme pour la teinte grise 

 de la partie supe'rieure que nous n'avons jamais vue aussi tranche'e 

 que dans celui de Natal. 



Quoique les trois exemplaires que nous avons vus, n'aient pas la 

 longue queue qui ne parait qu'a la saison des amours, nous ne 

 doutons pas qu'a cette epoque notre oiseau n'en soit aussi pourvu, 

 ce que viendront confirmer les naturalistes qui plus heureux que nous 

 se trouveront a meme d'en faire l'observation. 



6. Description of Platasterias, a new Genus of Astropec- 

 tinidce, from Mexico. By Dr. J. E. Gray, F.R.S. &c. 



[Eeceived January 23, 1871.] 



(Plate IX.) 



Mr. A.. Boucard has lately sent some reptiles and other animals 

 from Tehuantepec in Mexico to the British Museum, among which is 

 a specimen of a Starfish allied to the genus Astropecten, belonging 

 to a form which I do not recollect to have been previously noticed, 

 and evidently very different from any that I have ever before seen. 

 It differs from Astropecten in being much flatter, more like a deeply 

 divided Palmipes, without any marginal tessera and with a single 

 row of marginal spines. It is peculiar in the rays being very broad 

 near the base, and then contracted and separated from each other 

 by deep fissures. 



Platasterias. 



Body much depressed, flat, divided into five flat rays, which are 

 broad near the base and gradually tapering to the ends, suddenly 

 narrowed near the body and separated by deep fissures ; the margins 

 of the rays narrow, sharp-edged, with a single series of very close 

 short depressed mobile spines. The dorsal surface covered with 

 close transverse linear series of short papillae, which are covered at 

 the end with a number of very short spines or paxillce. The under 

 surface with a central longitudinal keel on each side parallel to the 

 ambulacra, with close transverse series of linear ridges, each covered 

 with a series of short close spines ; the ambulacra edged with a 

 series of elongate tapering acute spines, and with a tuft of similar 

 spines at the angles of the mouth between the ambulacra. 



Platasterias latiradiata, sp. nov. (Plate IX.) 



Body yellow when dry ; the rays five, flat, twice and a hall' 

 the length of the diameter of the body, broadly lanceolate. The 

 basal quarter suddenly dilated to its greatest width and then 

 gradually tapering to the end, the greatest width being two-fifths 



