SYSTEMATIC DESCRIPTIONS SPATANGINA. 73 



more or less, according as it is tilted. The anterior ambulacrum III is 

 hardly visible and the mouth is visible, but not clearly outlined. 



Eocene, St. Bartholomew limestone, St. Bartholomew, Guppy collec- 

 tion ex Cleve, holotype, 1 specimen only, the original of Cotteau's plate 

 6, figures 11 to 15, U. S. Nat. Mus. No. 115411. 



Genus HEMIASTER Desor, 1847. 



Type species. Spatangus bufo Al. Brongniart, 1822, Cuvier's Oss. 

 Foss., vol. 2, pp. 320, 604. 



There are 4 species of Hemiaster occurring as fossils in the West Indies; 

 of these I have seen only 1 , which is here described as new. 



Key to the West Indian Fossil Species of Hemiaster. 



Posterior petals I and V not half as long as the antero-lateral II and IV. 



Test abruptly narrowed posteriorly; petals II and IV moderately divergent H. cubensis 



Test not narrowed posteriorly; petals II and IV extremely divergent H. antillensis 



Posterior petals I and V much more than half as long as II and IV. 



Height of test over 80 per cent of length; test not sloping markedly to the front.. H. dewalquei 

 Height of test 50 to 60 per cent of length; test sloping markedly to the front H. berkeyi 



Hemiaster cubensis (d'Orbigny). 



Schizaster cubensis d'Orbigny in Agassiz and Desor, 1847, Catalogue Raisonne, Ann. Sci. 



Nat., ser. 3. vol. 8, p. 22. 

 Hemiaster cubensis Cotteau, 1881, Ann. Soc. Geol. Belgique, vol. 9, p. 41, plate 4, figs. 1 to 3; 



1897. Bol. Com. Mapa Geol. Espana, vol. 22, p. 73, plate 25, figs. 1 to 3. 



Cotteau cites this species as Pliocene or Recent, very rare in the island 

 of Cuba; from the d'Orbigny collection in the Natural History Museum 

 in Paris. 



Hemiaster antillensis Cotteau. 



Hemiaster antillensis Cotteau, 1881, Ann. Soc. Geol. Belgique, vol. 9, p. 31, plate 3, figs. 1 to 4; 

 1897, Bol. Com. Mapa Geol. Espana, vol. 22, p. 72, plate 24, figs. 1 to 4. 



Cotteau cites this species as Eocene (?), Santa Lucia and Concepci6n in 

 the district of Cienfuegos, Province of Santa Clara, Cuba; collections of 

 Dewalque in Liege and Comision del Mapa Geol6gico de Espaiia, Madrid. 



Hemiaster dewalquei Cotteau. 



Hemiaster dewalquei Cotteau, 1881, Ann. Soc. Geol. Belgique, vol. 9, p. 30, plate 2, figs. 7 to 9; 

 1897, Bol. Com. Mapa Geol. Espana, vol. 22, p. 75, plate 3, figs. 7 to 9. 



Cotteau cites this species as from the Eocene (?) of Cienfuegos, Cuba, 

 very rare; collection of Dewalque in Liege. 



Hemiaster berkeyi, new species. 



(Plate 12, Figure 10.) 



The following is a description of this species : 



Test large, cordiform, high, subconical, rounded below, from the highest 

 point of the test dorsally sloping anteriorly, posteriorly, and laterally to 



