TERTIARY MOLLUSCA. 145 



Spondylus species. 



In the Vaughan collection are numerous specimens of a species of 

 Spondylus which I have been unable to identify with any described 

 species. It appears to be more rotund than S. dumosus and S. scotti, 

 but less so than S. bostrychites. The ribs are uniform or slightly 

 alternating in size and set with the spines customary to the genus. 

 The finer sculpture/which is of much more diagnostic value than the 

 coarser, is entirely obliterated in the specimens at hand. 

 ^ Localities. — Northwest side of St. Jean Bay and point between Anse 

 Ecaille and Anse Lezard, St. Bartholomew, stations 6897, 6897 a, 6, 

 6924, Vaughan. 



Geologic horizon. — Eocene, near top of the conglomerate series and 

 beneath the main limestone bed. 



Plicatula densata Conrad. 



(Plate 11, Figures 12 o, 6.) 



Plicatula densata Conrad, Proc. Acad. Nat. Sci. Phila., vol. 1, p. 311, 1843. 

 Plicatula densata Conrad, Foss. of the Medial Tertiary, p. 75, plate 43, fig. 6, 1845. 

 Spondylus inornatus Whitfield, Miocene Pal. N. J., p. 34, plate 5, figs. 1, 2, 1895. 

 Plicatula densata Dall, Trans. Wagner Inst., vol. 3, pt. 2, p. 763 (ex parte), 1898. 

 Plicatula densata Dall, U. S. Nat. Mus. Bull. 90, p. 125 (ex parte), 1915. 



The following is Conrad's description of this species, 1845: 



"Ovate, thick, profoundly and irregularly plicated; inferior valve ventricose; 

 ribs acute, with arched spiniform scales; cardinal teeth large, curved, laterally 

 striated, crenulated on the margins; larger cardinal tooth in each valve 

 slightly bifid, broad; muscular impressions prominent. 



"Loc. Cumberland Co., New Jersey. 



"The valves have about 10 folds, and the lower valve closely resembles a 

 variety of Ostrea virqiniana." 



The Cuban form seems indistinguishable from the continental. 



Localities. — Santiago, Cuba, stations 3436, 3447, Vaughan; also at 

 Tampa, Chipola, and Oak Grove, Florida, and in the Miocene of New 

 Jersey. 



Type. — Philadelphia Academy? 



Figured specimen. — U. S. Nat. Mus. No. 167150. 



Modiolus (Botula) cinnamomeus (Lamarck). 



(Plate 14, Figures 4, 5.) 



Mytilus cinnamominus, etc., Chem., Conch. Cab., vol. 8, p. 152, plate 82, fig. 731, 1785 - 

 Modiola cinnamomea Lam., Anim. sans Vert., vol. 6, p. 114, 1819; ed. Desh., vol. 7, p. 25, 1835. 

 Modiolus (Botula) cinnamomeus Dall, Trans. Wagner Inst., vol. 3, p. 797, 1898. 

 Modiolus (Botula) cinnamomeus Dall, U. S. Nat. Mus., Bull. 90, p. 128, 1915. 



The following is Lamarck's description of this species: 



"M. testa subcylindrica, ventricosa, arcuata, utraque extremitate retusa; 



natibus subprominulis. 



"Habite les mers de PIsle de France. Coquille de couleur marron, ayant 



l'aspect d'un gland arqu6; a valves tres concave. Longueur, 37 mm. 



