B. Rathhun — List of the Brazilian Echinoderms. 141 



Verrill, A. E. Comparisoii of the Tropical Faunfe of the East and West Coasts of 

 America. Transactions of the Connecticut Academy of Arts and Sciences, vol. i, 

 part II, 1867.— Notice of the Corals and Echinoderms collected by Prof. C. F. 

 Hartt, at the Abrolhos Reefs, Province of Bahia, Brazil, 1867. Trans. Conn. 

 Acad., vol. i, part II, 1868. 



HOLOTHURIOIDEA. 

 Chirodota rotiferum stimpson. 



Amer. Jour. Sci., xxix, p. 134, 1860; Yerrill, Trans. Conn. Acad., i, p. 37], 1868 ; 

 Selenka, Zeitschr. fiir Wiss. Zool., 1867, p. 367 (roiifera). 



Abrolhos Reefs (Hartt, '67). Plataforraa, Bay of Bahia, buried in 

 the sandy mud of tide pools (Rathbun). Florida (Pourtales). 



Thyone (Sclerodactyla) Braziliensis Verriii. 



Trans. Conn. Acad., i, p. 370, 1868. 



Abrolhos Reefs, under dead corals, in the shallow tide pools and 

 holes in the reefs (Hartt, '67j. Plataforma, Bay of Bahia, buried in 

 the mud or impure sand, filling the pools and crevices of the rocky 

 shores (Rathbun). 



Thyonella, Sp. 



Plataforma, Bahia (Rathbun), associated with Thyone Braziliensis. 



This species of Thyonella resembles very closely in external appear- 

 ance and characters T. genunata Verr.,* of the Southern coast of the 

 United States, with which it might readily be united, except for the 

 very different nature of its skin-plates. These are mostly of one 

 kind, corresponding nearly with the larger, elongate plates of T. 

 yemmata. They are large and flattened, and irregularly fusiform, 

 oblong or even triangular in outline, with generally two, sometimes 

 more, rows of large openings. At times the openings are irregularly 

 scattered and of smaller size. In addition there are more rarely 

 slender, curved plates, with two or three perforations at each end 

 and in the middle, or with a row of perforations. 



Holothuria, Sp. 



Plataforma, Bahia (Rathbun), associated with Thyone Braziliensis. 



A specimen of this species, in alcohol, but not mucli contracted, 

 measures in length, about 125'"'", greatest diametei", about 24'"°\ The 



* Thyonella genimata Verr., Amer. Jour. Sci. and Arts, III, vol. iii, p. 437, 1872. 

 Colochirus gemmatus Pourtales, Proc. Amer. Ass. Adv. Sci., 185], p. 11. 

 Thyonidium gem.matum Selenka, Zeitschrift fiir Wissenschaftl. Zool., vol. xvii, p. 

 345, 1867. 



