90 ME. H. WOODS ON THE MOLLUSCA [Feb. 1 896, 



Bemarks. — Sowerby's types, which come from the Lower Chalk 

 of Kent, are in the British Museum. Barrois states that T. Heberti 

 differs from T. gemmatus by the ridges on the margin of the 

 umbilicus, but in the specimens figured by Sowerby the umbilicus 

 cannot be seen ; in examples from the Chalk Rock, however, the 

 ridges are present, so that there seems to be no reason for sepa- 

 rating T. Heberti from the English species. 



T. Guerangeri, d'Orbigny, can be distinguished from this species 

 by the more angular whorls, whilst in T. Goupilianus of the same 

 author the whorls are much more convex. 



Distribution. — England : Lower Chalk of Kent and Sussex {fide 

 Morris and Dixon). Chalk Rock of Dover, Winchester, Oldborough 

 Castle, Cuckhamsley, Luton cutting, Hitchin, Reed near Royston,, 

 Barkway, and Underwood Hall near Dullingham. Northern France i 

 Cenomanian of Ste. Parres-aux-Tertres, near Troyes, and Vitry-le- 

 Francois ; zone of Bel. plenus at Neuville-au-Pont, Charontelles 

 (Marne), etc. ; Turonian of Yillecien, near Joigny (Yonne). 



Ttjebo gemmatus, var. a. 



There are several specimens in the Montagu Smith Collection 

 which agree with T. gemmatus, except in being much longer ; the 

 shell is almost twice as long as broad and consists of 9 whorls. It 

 will, I think, be best to regard this form simply as a variety of 

 T. gemmatus. 



Distribution. — Chalk Rock of Cuckhamsley. 



Family Capulidae, Fleming. 



Genus Ckepidula, Lamarck, 1799. 

 Ckepidula, sp. 



Bemarks. — Some specimens of a Crepidula closely resemble O. 

 Cooksonioe, Seeley, 1 from the Cambridge Greensand (= Calyjptrcea 

 Sanctce-Crucis, Pictet and Campiche, from the Upper Gault of Ste.- 

 Croix), except that the internal plate is relatively smaller. There 

 is a good deal of variation in the form of the shell, some examples 

 being much elevated, others depressed ; in the former the cast of 

 the septum has the appearance of an inverted U, but in the latter 

 the limbs of the U diverge widely. 



All the specimens are in the form of internal casts, and con- 

 sequently I refrain from giving a specific name. 



Distribution. — Chalk Rock of Cuckhamsley (Montagu Smith Col- 

 lection). 



1 H. G. Seeley, Ann. Mag. Nat. Hist. ser. 3, vol. vii. (1861) p. 291, pi. xi. 

 f. 18. See also A. J. Jukes-Browne, Quart. Journ. Geol. Soc. vol. xxxi. (1875) 

 p. 294 ; J. S. Gardner, ibid. vol. xxxiii. (1877) p. 201, and Geol. Mag. 1877, 

 pi. xvi. f. 19, p. 556. For C. Sanctce- Cruris, see Pictet and Campiche, ' Foss. 

 du Terr. Cret. de Ste.-Croix,' 1864, p. 696, pi. xcvii. figs. 5-8. Mr. Gardner 

 considers that these species, and perhaps also Galericulus alius, Seeley, are 

 identical with Crepidula gaultina, Buvignier. 



