54 FOSSIL ECHINI OF THE WEST INDIES. 



Under Macropneustes 2 fossil species (see Key, p. 84). 

 Under Brissus 2 fossil species (see Key, p. 86). 

 Under Eupatagus 7 fossil species (see Key, p. 88). 

 Under Breynia only 1 fossil species, Breynia cubensis. 



Family ECHINONEID^ A. Agassiz, 1881. 



Echinoneidae A. Agassiz, 1881 - Echinonida? Wright, 18SS. 



Genus ECHINONEUS Leske, 1778. 



Type species. — Echinoneus cyclostomus Leske, 1778, Add. ad Klein, 

 p. 109. 



There seem to be only 2 species recognizable among the fossil species 

 of this genus in the West Indies. 



Key to the West Indian Fossil Species of Echinoneus. 



Ambitus nearly circular, the shorter diameter being over 90 per cent of the longer. E. orbicularis 

 Ambitus elliptical, the shorter diameter being less than 90 per cent and usually about 75 



per cent of the longer E. cyclostomus 



Echinoneus orbicularis Desor. 



Echinoneus orbicularis Desor, 1846, Catalogue Raisonne, Ann. Sci. Nat., ser 3, vol. 7, p. 144. 

 Cotteau, 1897, Bol. Com. Mapa Geol. Espana, vol. 22, p. 47, plate IS, fig. 4. 



This species is recorded by Cotteau as known fossil in the West 

 Indies from a single specimen from Recent calcareous concretions in 

 the island of Cuba. The specimen is in the d'Orbigny collection in 

 the Paris Museum. 



Echinoneus cyclostomus Leske. 

 (Plate 9, Figures 4, 5.) 



Echinoneus cyclostomus Leske, 1778, Add. ad Klein, p. 109. Guppy, 1866, Quart. Jour. 



Geol. Soc. London, vol. 22, p. 301. Cotteau, 1897, Bol. Com. Mapa Geol. Espana, 



vol. 22, p. 48, plate 15, figs. 5 to 9. H. L. Clark, 1917, Mem. Mus. Comp. Zool., 



vol. 46, No. 2, p. 102. 

 Echinoneus semilunaris A. Agassiz, 1873, Revision of Echini, p. 118; 1883, Mem. Mus. 



Comp. Zool., vol. 10, No. 1, p. 90. 

 Echinoneus Cotteau, 1875, Kongl. Sven. Vet. Akad. Handl., vol. 13, No. 6, p. 14, plate 1. 



figs. 28 to 30. 

 Echinoneus minor Guppy (non Leske), 1882, Scientific Assoc. Trinidad, Proc., part 12, p. 195. 



The following is a description of this species : 



Test oval, low, rounded, wider posteriorly than anteriorly. Peristome 

 strongly elliptical, a little anterior to the middle of the test, set on a slant 

 from the antero-posterior axis of the test. Periproct large, ovate, broadest 

 anteriorly, situated halfway from the peristome to the posterior border 

 of the test. Ambulacra apetaloid, flush with surface, narrow, and broadest 

 above the ambitus. Poriferous areas are very narrow. Apical system a 

 little anterior to the middle of the test, but the details of apical plates or 

 pores could not be made out. Tubercles small, not very closely associated 

 dorsally; ventrally more closely associated, as shown in the figures. 



This species is represented by a single specimen from Anguilla in the 

 National Museum. Cotteau says that he had a single specimen in 

 the Cleve collection from Anguilla, on which his figures were based. 

 Guppy also had a single specimen from Anguilla, as stated by him in 

 his published paper. Whether this specimen in the U. S. National 



