36 FOSSIL ECHINI OF THE WEST INDIES. 



Brown says that C. concavus is the commonest echinoid in the Antigua 

 white limestone (Antigua formation) and was found in great numbers 

 at Hodges Bay, Antigua (4 specimens in Philadelphia Acad. Nat. Sci., 

 No. 1658) ; along the shore at Willoughby Bay, Antigua (9 specimens, 

 Philadelphia Acad. Nat. Sci., No. 1659); and at High Point, Antigua. 

 Oligocene, Havana, Cuba, from de la Torre collection, 1 specimen, 

 Mus. Comp. Zool. No. 3233. Cotteau, in his Spanish report, gives the 

 horizon as "Miocene" and the localities, Province of Santa Clara, also 

 ingenios San Marco and San Lino and Cienfuegos, Cuba, collection of 

 Comision del Mapa Geol6gico de Espafia, Madrid. 



Clypeaster caudatus, new species. 



(Plate 3, Figures 1, 2.) 



The following is a description of this species : 



This species, while near to others, has features which distinguish it from 

 rosaceus and concavus. The test is massive, quite uniformly arched, but 

 with rather a gradual slope from the apical disk to the anterior border of 

 the test, and posteriorly a less marked slope to the rather abruptly truncated 

 posterior border. The outline of the test is rounded anteriorly; posteriorly 

 it is abruptly rounded and truncated, even slightly reentrant on the median 

 line. The ambulacral petals are very broad and long, nearly closed at the 

 tips and pinched up so that the interporiferous area at the end of the petal 

 terminates in a tail-like tip, especially in ambulacra I, V and II, IV. The 

 anterior petal III is longer than the anterior pair II and IV and is of the same 

 length as the posterior pair I and V. The anterior petal III at its broadest 

 part has the same width as petals II and IV, but is distinctly narrower than 

 petals I and V. The interporiferous areas of the petals are wide and only 

 very slightly raised above the general outline of the test. The apical disk 

 is nearly central and the 5 genital pores are clearly shown in the holo- 

 type. As the ventral side of the test is hidden in both specimens, no 

 observations can be made on the peristome, periproct, or other ventral char- 

 acters. Both specimens are so worn that the tubercles are largely eroded 

 away, but dorsally where visible they are numerous and closely associated. 

 Ventrally the tubercles are somewhat larger and very densely crowded, 

 so that there is almost no intertubercular tissue. 



The holotype measures about 45 mm. in height, 141 mm. in length 

 and 121 mm. in width. A smaller specimen, the paratype, measures 

 25 mm. in height, 80 mm. in length, and 70 mm. in width. Clypeaster 

 caudatus is very near to C. concavus; the small specimen differs only 

 in the more markedly arched test and in the fact that the tips of the 

 petals are pinched together and pulled out distally. 



Miocene, Gurabo formation, or the Mao Adentro limestone, Rio 

 Gurabo, near Los Quemados, not in place, probably from Zone C, 

 Dominican Republic, Dr. C. J. Maury collector, 1907, holotype, 

 U. S. Nat. Mus. No. 328235. Paratype with same locality and data, 

 U. S. Nat. Mus. No. 328236. 



