324 PROCEEDINGS OF THE ACADEMY OF [1890. 



This species is found throughout the West Indian region, extend- 

 ing northwards to Beaufort, N. C. and southwards to Armacao, Bra- 

 zil. Professor Agassiz also records it from Cape Dos Bahias, Argen- 

 tine Republic. 



Echinaster Brasiliensis, MUller and Trofchel. System der Asteiiden 1S42, ji. 22, 

 Tab. l,fig. 4. (?) 



Perrier, Arch. de. Zool. Exp. Vol. IV, 1875, p. ?>(37. 

 Lutkcn, Vidensk. Meddel. 1859, p. 93. 

 Rathbun, Trans. Conn. Acad. Vol. V, 1879, p. 148. 

 Ludwig, Mem. Cour. Acad. Roy. Belg. T. XLIV, 1882. No. 5, p. 7. 



Two starfishes obtained upon the beach at Progreso have been 

 referred to this species. The larger specimen is about 80 mm. in 

 diameter. The length of the radius of the disk, to that of the arm, 

 is about as one to five. The arms are cylindrical and tapering. 

 The spines of the surface of the arms and disk are small, not longer 

 than the ambulacral spines, and form nine irregular rows upon the 

 surface of the arms. There are about twenty five spines in a row from 

 the middle of the disk to the tip of the arm. The ambulacral spines are 

 arranged in three more or less perfect rows. The two outer rows 

 are of equal size and the spines are opposite to one another ; the 

 spines of the innermost row are much smaller and alternate with the 

 larger spines. 



The smaller specimen is about 70 mm. in diameter and has only 

 seven imperfect rows of spines, with about 20 spines in a row. 



The specimens when alive were of a rust-red color, darker above 

 than beneath. In alcohol they have become a light dirty brown. 



I have figured the larger of the two specimens collected, PI. VIII, 

 figs. 16-18. 



The specimens found in Yucatan, agree with the description of 

 the forms referred by Mr. Rathbun to this species from Rio Formoso, 

 Pernambuco, Brazil. 



The synonymy of Echmaster Brasiliensis and of the other species 

 of Echinaster inhabiting the western shores of the tropical Atlantic 

 is in a very unsatisfactory condition. Miiller and Troschel give 

 Oihilia multispina of Gray ^ as a synonym of this species, but it 

 appears to me very doubtful if this form is the same. 



The locality of the specimen described by Gray is unknown. His 

 description runs thus : " Rays short, depressed, broad, rather more 



1 Annals and Mag. Nat. Hist., Vol. VI, 1840, p. 282. 



