SI 

 TAPES GEOGRAPHICUS AND T. PULLASTRA. 



By R. B. woodward. 



(Read before the Society, Jan. o, 1901). 



Mr. J. T. Marshall in his note on this subject {antea p. 27) leaves 

 much to be desired in the way of accuracy, both in his inferences and 

 his references. The sentence "judging them only from a comparison 

 of their shells" has no justification whatever in anything in my note; 

 equally baseless is the assumption that "Mr. Woodward, on the other 

 hand, has .... apparently ignored the shells." Not being given to 

 rush into print without adequate research and investigation, a careful 

 study of the specimens in the Natural History Museum was made 

 both before writing my previous note and in the present instance, and 

 in each case in company with my friend and colleague, Mr. E^. A. 

 Smith, whose permission I have to state that he also considers the 

 two forms to be distinct species. Further, when Mr, Marshall asserts 

 I am mistaken in considering that Jeffreys was unaware of the occur- 

 rence of T, pullastra in the Mediterranean, he has manifestly over- 

 looked in the very paper he quotes^ Jeffreys' statement : " I have 

 examined many hundred specimens of the southern form, T. geo- 

 graphicns from the Mediterranean and Adriatic ; and my former 

 opinion of its being the same species as the northern form, T. pul- 

 lastra, has been most fully and satisfactorily confirmed." This clearly 

 shows that Jeffreys was then unaware, or had forgotten, that the 

 northern form occurred in the Mediterranean, side by side with the 

 southern form ; but, of course, holding as he did that the two forms 

 were one species, he gives the range for that as quoted by Mr. 

 Marshall. The further citation" is immaterial, since it only refers to 

 Mr. Marshall's own echo of Jeffreys' opinion. 



Now, as to the specific distinctness or not of these two forms 

 opinions differ, but to Mr. Smith and myself it seemed that the differ- 

 ences were not merely "superficial" (the exact meaning of Mr. 

 Marshall's sentence on this point is far from lucid). Not only is 

 T. geographicus narrower and longer in form, even when compared 

 with the most elongate forms of T. pullastra we could find (from 

 Hunstanton, Norfolk; and from the Mediterranean) but it differs in 

 other respects in its contour ; whilst the hinge-plate is not so pro- 

 minent, sloping back more into the valve, and the posterior portion 

 of the hinge has a strong purplish tinge not observable in T. pullastra, 

 which, on the other hand, has sometimes a purple stain beloiv the 



1 Proc. Zool. Soc, 1 88 1, p. 717. 



2 Joiirn. of Conch., vol. 8, p. 27, 1895. 



