TRIBE PECTIN [DES. 289 



P. Philippinarum. Hartley, in Soiv. Th. 1, p. 436, t. 90,/. 9, 11, 

 13, 14. Solid, lineated with red or black on a white ground. Folds 

 large, numerous, rarely forked, angular ; somewhat imbricated at the 

 angles. Var. Devoid of ridges. 2. Philippines. 



P. Dubia. Hartley, in Sow. Th. 1, p. 437, t. 91,/. 19. Thin, folia- 

 ceous, depressed, roundish, pinkish brown, with a few scattered brown 

 spots ; armed with radiating rows of occasionally upturned vaulted 

 scales ; folds short, irregular, interrupted. 1 i. Philippines. 



SPONDYLUS. 



Inequivalve, attached, auriculated, irregularly foliaceous, longi- 

 tudinally ribbed, generally spinous. Beak of the lower valve usually 

 produced ; its fiat triangular hinge-area cleft by a linear furrow, in 

 which are imbedded the remains of the earlier cartilage ; the latter is 

 internal, and seated in a pit between the massive teeth of each valve. 



S. G^ederopus, Lin. 1136 (partly). — Lam. 1. — Ch. 7,/. 459; & 9, 

 /. 984, 5.—E. t. 190, /. l.—Phil Sic. 1, p. 81.— Chenu, II. C. 

 Spoitd. t. %.—Sow. Th. 1, p. 418, t. 87,/. 29 ; pi, 88,/ 41.— (Kn. 5, 

 t. 13,/ 1). — Var. S. Aculeatus, Phil. Sic. Purplish crimson, more 

 rarely white, with only the beaks and margin tinged with that colour. 

 Radiating costellae numerous, little elevated, close-set, of moderate 

 breadth, usually alternately larger and smaller (yet none peculiarly 

 large or prominent), thickly set with very strong Ungulate spines of 

 moderate length ; their intervals not excavated or concave, but 

 roughened, by about 5 very narrow and most minutely squami- 

 ferous elevated radiating lines. 4. Mediterranean. 



S. Americanus. — S. GLederopus, Ch. 7 ',/. 465 (named S. Domini- 

 censis by Bolten).— W. t. 9,/ 1.— S. G. var. D. p. 209.— S. A. 

 Lam. 2. — E. t. 195,/ 1, 2. — Sow. Conch. Man. Front. — Reeve, C. S. 

 t. 116, / I.— Chenu, II. C. Spond. t. 5 ; t. 3, / 31.— Sow. Th. 1, 

 p. 418, t. 88,/ 42 ; t. 89,/ 64. — Young, S. Arachnoideus, Lam. 3. 

 — (Kn. 5, t. 9,/. 1). Large; both general surface and raised pro- 

 cesses scarlet near the beaks, and white towards the margin ; rayed 

 with very numerous rather depressed narrow ribs and costellge, of 

 which about the 6 principal are armed with close-set very elongated 

 spathulate laminae, which only in finely developed specimens have 

 a slight tendency to foliation at their apices. The costellae are 

 aculeated with flat slender spines, several rows of which intervene 

 between the laminae. 6. America, The S. Avicularis of Lamarck 

 (No. 10), his S. Longispina (No. 8), and the S. Striato-spinosus of 

 Chenu (II, Con, Sp. t. 23,/ 1) are, in all probability , varieties of this 

 shell, 



u 



