VELOPECTEN. 21 ( .) 



side otter ribs (sometimes four or five) are introduced; these are usually smaller, 

 and may be quite close together, but in old specimens they become widely 

 separated ventrally. Both ribs and furrows are crossed by numerous line, close- 

 set, regular, concentric ridges. Anterior ear with about seven primary and seven 

 secondary ribs. Posterior ear smaller and more distinctly limited. 



Affinities. — Himiites Salteri, Seeley, from the Red Limestone of Hunstanton, is 

 founded on a portion of the left valve ; it appears to me to be only a large example 

 of l r . Stnderi, in which the main ribs are less prominent than usual owing to the 

 abrasion of the shell. See also V. trilinearis (below). 



Remarks. — The state of preservation of the examples of this species varies con- 

 siderably, but is usually rather unsatisfactory. In the specimens from Warminster, 

 where the species appears to be rare, the shell is preserved, and the ornamentation 

 is very well shown, but in those from Folkestone the shell has usually disappeared. 

 The examples from the Cambridge Greensand are internal casts in phosphate, in 

 which there is no trace of the ears, and whilst some of the principal ribs are shown 

 the details of the ornamentation are wanting. The specimens from the Red Lime- 

 stone of Hunstanton are usually considerably larger than those from the Cambridge 

 Greensand, and have the shell preserved in part at any rate ; in some cases the 

 fine ornamentation is clearly shown, but often it is indistinct owing to the outer 

 layers of the shell having disappeared ; in these large forms the main ribs become 

 much less strong near the ventral margin, or, in some cases, almost in- 

 distinguishable. 



Types. — From the Gault of the Perte du Rhone. The type of Hinnites Salteri, 

 Seeley, from the Red Limestone of Hunstanton, is in the Woodwardian Museum, 

 Cambridge. 



Distribution. — Upper Gault (zone x) of Folkestone. Cambridge Greensand 

 (derived from the Upper Gault). Red Limestone of Hunstanton. Upper Greensand 

 of Warminster. 



Velopecten trilinkaeis (Seeley), 1861. Plate XLII, fig. 5. 



1861. Hinnites trilinearis, H. G. Seeley. Ann. Mag. Nat. Hist., ser. 3, vol. vii, 



p. 119, pi. vi, fig. 2. 

 1866. — vav., Seeley. Ibid., vol. xvii, p. 178. 



Remarks. — The form named Hinnites trilinearis by Seeley was founded on a few 

 imperfect specimens from the Cambridge Greensand. They seem to differ from 

 the English examples of V. Studcri in having the primary ribs on the left valve 

 stronger and more widely separated, but they approach very closely some of the 

 specimens of that species figured by Pictet and Campiche, especially in having 



