12 DE. T. DAVIDSON ON EECENT BEACHIOPODA. 



5. LioTHYRis SPHENOIDEA, Philippi, sp. (Plate II. figs. 17-22.) 



Terebratula sphenoidea, Philippi, Enum. Moll. Siciliie, vol. ii. p. 68, tab. xviii. fig. 6, 1844; G. 

 SegLieuza, Pal. Malac. dei Terreni Terziarii del distretto di Messina, Memorie della Soc. Italiana di 

 Scienze Naturali, p. 24, pi. ii. figs. 1-5, 1865 ; also Studii Paleontologici sui Bracbiopodi dell' Italia 

 Meridionale, pi. i. figs. 18-26, Pisa, 1871. 



Terebratula cubensis, Pourtales, Contributions to the Fauna of the Gulf Stream at great depths. Bull. 

 Mus. Comp. Zocil. vol. i. pp. 109 & 124, 1867 ; Dall, lleport on the Brachiopoda obtained by the United 

 States Coast Survey Exp., Bull Mus. Comp. Zo51. vol. iii. pp.3-9, pi. i. fig. 2, 1871; Davidson, Report 

 on the Brachiopoda, Voy. H.M.S. 'Challenger,' p. 28, pi. ii. figs. 10-11, 1880; Dall, Bull. Mus. 

 Comp. Zool. vol. ix. p. 103, 1881. 



Terebratula vitrea, var. sphenoidea, Jeffreys, Ou the Mollusca procured during the ' Lightning ' and 

 'Porcupine' Expeditions 1868-70, Proc. Zool. Soc. p. 404, pi. xxii. fig. 6, 1878. 



Shell longitudinally more or less trigonal, broadest and rounded anteriorly, tapering 

 posteriorly, lateral marginal line flexuous, that of the dorsal valve forming an outward 

 curve, flexuously varying with age. Dorsal valve uniformly convex, sometimes I'ather 

 inflated ; ventral valve somewhat deeper than the dorsal one, longitudinally broadly 

 flattened, sides of the flattened portion sloping away rather abruptly ou either side, 

 giving the valve a somewhat subquadrangular aspect ; beak moderately incurved and 

 truncated by a circular foramen sej)arated from the hinge-line by a narrow deltidium. 

 Surface smooth, sometimes marked by fine radiating lines. Loop narrow, small, and 

 simple, bent-up band connecting the principal stems of the loop long and narrow. 

 Colour soiled white. Length 1 inch 3 lines, breadth 11 lines, depth 9 lines. 



Mab. Recent. Atlantic (Jeffreys). West-African coast (' Travailleur ' and 'Talisman' 

 Expeditions). Gulf of Florida in depths of 100-200 fathoms, rarer towards east end 

 of reefs (Pourtales). Coast of Cuba (Sigsbee), off Havana 270 fathoms. Barbados 

 100 fathoms, St. Vincent 88 fathoms, Martinique 210 fathoms. Ofi" Ascension 420 

 fathoms (' Challenger ' Expedition). Off Morocco (' Talisman ' Expedition) in 298 to 

 818 fatlioms. 



Fossil. In Pliocene rocks of Calabria and Sicily (Philippi and Seguenza). 



Obs. In 1844, Philippi described and figured, as his Terebratula sphenoidea, some 

 fossil Pliocene specimens he had collected in the valley of Lamanto in Calabria. Subse- 

 quently Signor Seguenza found the same fossil in Philippi's locality, as well as in rocks 

 of the same age in Sicily. In 1878, Dr. Gwyn Jeffreys described and figured as Tere- 

 bratula vitrea, var. sphenoidea, a living specimen Avhich he had dredged during the ' Por- 

 cupine ' Expedition in 1870, from the Atlantic, at depths of 292, 374, and 994 fathoms, and 

 remarks : — "After a protracted and very careful examination of my specimens, which I had 

 considered the T. sphenoidea of Philippi, and having compared them with fossil specimens 

 sent me by Prof. Seguenza as Philippi's species from the Sicilian Tertiaries, as well as with 

 a series of T. cubensis which I received from Count Pourtales and Professor Alexander 

 Agassiz, and also after a close comparison of all these specimens with the description and 

 figures given by Philippi, Seguenza, Pourtales, and Dall, I am convinced the T. sphenoidea 

 and T. cubensis are the same, and constitute a well-marked variety of T. vitrea. The 

 loop in T. sphenoidea and T. cubensis is precisely similar." In this last remark, Dr. Gwyn 



