Vol. 62.] LIASSIC DENTALIID^. 583 



T.l. ' Cracombe.' fCrayconibe, near Evesham.] 

 H. Lower Lias. [Hettangian.] 

 ?/. \_marmorece7\ 

 ■Colin. H. E. Strickland. [Cannot be found.'] 



JDentalium minimum, Tate, pars, 1863-64, Quart. Journ. Geol. Soc. vol. xx, p. 111. 



Syn. 1843. JDentalium tenne, Portlock, ' Report on the Geologv of Londonderry, &c.' 

 p. 118 (non Goldfuss, 1841). 

 1856. D. Andleri, Oppel, ' Die Juraformation ' p. 93 (probably). 

 1867. D. tenue, Tate, Quart. Journ. Geol. Soc. vol. xxiii, p. 311. 

 1870. Z>. Portlocti, Tate, Proc. Belfast Nat. F. C, App. i, p. 17 & pi. i, 

 fig. 15. 

 ? 1876. D. etalense, Tate, pars, ' The Yorkshire Lias ' p. 332. 



Protolog. — 'Shell cylindrical, smooth, very minute, slightly 

 •curved, about a quarter of an inch in length.' 



Remarks. — This description also represents the main features of 

 Dentalium Poriloclci, Tate, but it may be added that Tate's specimen 

 tapers regularly from the anterior to the posterior end, has a 

 circular section, and measures about 4-5 mm. in length, 0*5 mm. 

 across the section of the anterior end, and 0*25 millimetre across 

 the posterior end. 



In 1843 Portlock: obtained fragments of a small Dentalium, con- 

 cerning which he gave the following information : — 



• JDentalium tenue (Portlock). — Aghanloo, Ballymaglin, and Ballycarton. 

 Fragments of this delicate Dentalium occur, with Modiola minima, in a fine 

 calcareous grit ; the longest, "4 of an inch, is about "04 of an inch in diameter 

 at the largest end, and tapers to a fine point. It is very slightly curved. 

 Magilligan, Craig, and Gortmore; hard calcareous grit.' (' Eeport on the 

 Geology of Londonderry, &c.' p. 118.) 



In the following year James Buckman published the very brief 

 description which has already been given (protolog), of an equally- 

 small scaphopod procured from beds of about the same age' at 

 €raycombe, near Evesham, and assigned to the fossil Strickland's 

 manuscript name of Dentalium minimum. 



Ralph Tate subsequently pointed out that Dentalium minimum, 

 Strickland-Buckman, was identical with Portlock's D. tenue. 1 As, 

 however, the specific name D. tenue was preoccupied by a Dentalium 

 figured by Goldfuss (to which the specimen under consideration was 

 not referable), Tate retained Strickland's denomination, abandoning 

 Portlock's name. He says : — 



' D. minimum I have found pretty frequently on the west shore of Island 

 Magee, Co. Antrim. I have also obtained it in great abundance in the 

 Lower Lias clay-pits off the Leckhampton Road, Cheltenham. The Irish 

 examples are less curved and elongated and more slender than the Cheltenham 

 forms.' 



Eor some reason, however, in 1867, Tate revived Portlock's name 

 of D. tenue 2 for the small shell from the anc/ulata-heds. This can 

 be seen from his published work, and presumably at this time he 

 also regarded the Cheltenham specimens as belonging to the same 



1 Quart. Journ. Geol. Soc. vol. xx (1864) p. 111. 



2 Ibid. vol. xxiii (1867) p. oil. 



Q. J. G. S. No. 248. 2 s 



