144 GEOLOGY AND PALEONTOLOGY OF THE WEST INDIES. 



gin fluted within; posterior ears oblique, with imbricating growth-lines and 

 one simple radiating rib adjacent to the abruptly sloping submargins. 

 Alt. about 46 mm. ; lat. . about 45 mm. ; alt. of largest specimen about 70 mm. 



This species, which is curiously intermediate between Pecten and 

 Spondylus, probably belongs to the subgenus Hinnites. The sculpture 

 and ears are distinctly pectiniform, but the discrepancy in the shape 

 and size of the valves is like that of Spondylus. 



Localities. — Northwest of St. Jean Bay, point between Anse Ecaille 

 and Anse Lizard, and point between Colombier Point and bay next to 

 St. Jean Bay, St. Bartholomew (stations 6897, 6897a, 6, 6905, 6924), 

 Vaughan. 



Geologic horizon. — Eocene. Near top of the conglomerate series and 

 beneath the main limestone bed. 



Type.— TJ. S. Nat. Mus. No. 167124. 



Spondylus bostrychites Guppy. 



(Plate 11, Figures 11 a, 6.) 



Spondylus bifrons Sowerby, Quart. Jour. Geol. Soc. London, vol. 6, p. 53, 1850 (date of 



imprint, 1849). Not of Goldfuss, 1835. 

 Spondylus bostrychites Guppy, Proc. Sci. Asso. Trinidad, p. 176, 1867. 

 Spondylus bostrychites Gabb, Trans. Amer. Phil. Soc, vol. 15, n. s., p. 257, 1881. 

 Spondylus bostrychites Dall, Trans. Wagner Inst. Sci.., vol 3, pt. 4, p. 758, 1898. 

 Spondylus bostrychites Dall, U. S. Nat. Mus. Bull. 90, p, 124, plate 19, fig. 4, 1915. 

 Spondylus bostrychites Maury, Bull. Amer. Pal., vol. 5, p. 354, plate 58, fig. 4, 1917. 



The following is Sowerby's description of this species, 1849 : 



"Testa subregularis, rotundata, ventricosa, margine latiusculo, valide 

 denticulato; extus radiatim costata, costis 5 ad 6 spiniferis; area cardinali 

 alterius valvse angustissima, alterius latiori." 



The shell is orbicular, pectiniform, nearly equivalve, with very 

 small submargins. The spinose ribs are separated by numerous finer, 

 spineless ribs bearing minute, close-set (2 or 3 per mm.), erect scales. 

 The short submargins and more rotund form distinguish S. bostrychites 

 from S. dumosus. 



Guppy's collection, now in the National Museum, contains 4 speci- 

 mens labeled types — 2 specimens from Jamaica and 2 from Anguilla. 

 The Jamaican forms have coarser intermediate ribs than those from 

 Anguilla and perhaps other differences might be detected if a larger 

 suite of specimens were available for comparison. I have not seen 

 Guppy' s description and consequently do not know which form is the 

 true S. bostrychites. Sowerby's type is from Santo Domingo. 



Localities.— Crocus Bay, Anguilla, stations 6894, 6965, 6967; Friar's 

 Hill, Long Island, and Willoughby Bay, Antigua, stations 6856, 6869, 

 6881, Vaughan; also at Pontou, Santo Domingo; Bowden, Jamaica; 

 Tampa, Florida. 



Geologic horizon. — Oligocene. 



Types.— U. S. Nat. Mus. Nos. 115522 or 115523. 



Figured specimen.— U . S. Nat. Mus. No. 167140. 



