THE 



GEOLOGICAL MAGAZINE. 



NEW SERIES. DECADE II. VOL. VIII. 



No. IX.— SEPTEMBER, 1881. 



I. — Note on some Gasteropoda from the Portland Rocks of the 

 Vale of Wardour and of Bucks. 



By "Wilfrid H. Hudleston, M.A., P.G.S., 



President of the Geologists' Association. 



(PLATE XI.) 



FOR many years English palEeontologists were content with the 

 limited number of Portlandian Gasteropoda described by 

 Sowerby — principally from internal casts — in Fitton's celebrated 

 paper on the " Strata below the Chalk." Other authors have 

 described a stray species here and there : still the list was scanty, 

 and not only scanty but indefinite ; and many ingenious guesses 

 have been hazarded as to the true affinities of such species as 

 Biiccinuji angulatiim, and Buccinum naticoides. 



Until a very short time ago the following may be regarded as a 

 full list of the Gasteropoda of the Portland limestones of this country, 

 viz. Buccinum angulatiim, Sow., Buccinum naticoides, Sow., Natica 

 elegans, Sow., Cerithium Portlandicum, Sow., C. concavum, Sow., 

 Neritoma sinuosa, Morr. (Sow.), Fleurotomaria rugata,^ Benett. Of 

 these, " Buccinum naticoides " (? Ampullaria elongata, Benett) is stated 

 by Damon to be one of the prevailing fossils of the Eoche. Mr. 

 Blake also notes it as one of the fossils of the building stones of 

 Portland Isle. It is presumable, therefore, that a form does exist 

 to which this name may apply, though its affinities have never 

 been investigated. The identifications in other districts seem to 

 me very doubtful, and in many cases are probably nothing more 

 than squeezed casts of Natica elegans. Buccinum angulatum is better 

 known to collectors, though hitherto only found as a cast. It is 

 certainly not Pteroceras Oceani, as has been suggested by some, and 

 its true position and affinities have long remained a subject for 

 speculation. Should the conjecture hazarded below prove to be 

 correct, the corresponding shell will have been found at last. 



Thus, out of seven species enumerated, one is very doubtful, 

 whilst correct descriptions of some of the others are wanting. Yet, 

 until the appearance of Mr. Blake's paper," this was all the informa- 

 tion available with respect to the Gasteropoda of our Portland Rocks 



1 It is scarcely worth while to include LiUorhia paucisulcata, Phillips, in this list. 



2 Portland Rocks of England, Q.J.G.S. (1880) p. 225. 



DECADE II. — VOL. VIH. — NO. IX. 25 



