•WEBB : BRITISH SPECIES OF TESTACELLA. 53 



1888. J. W. Taylor. — On the specific distinctness and geographical 

 distribution of Tcst.xcella scutiilitin, G. B. Sowerby, Journ. of Conch., vol. v. 

 ,PP- 337. figs. 



In this paper the result of anatomical work, by the late Charles Ashford, 

 is given. 



1893. Walter E. Collinge. The Morphology of the Generative 

 System of the Genus Testacella. Ann. Mag. Nat. Hist , ser. 6, vol. xii., 

 pp. 21-25, pi. i. 



Briefly the facts are these. In 18S5 Mr. Charles Asliford 

 found that Testacella sciitiiliiin unlike T. haliotidca resembled 

 T. maugei in having no flagellum to the penis. Mr. Taylor 

 published these results (1888), and gave figures of the genital 

 organs of the two first species. Mr. Collinge (1893) gave 

 an account of the organs of T. haliotidca following Lacaze- 

 Duthiers * ; at the same time he criticized Mr. Taylor's descrip- 

 tion and figure, and proceeded to compare and figure the system, 

 of all three species. 



During the last few years the writer has dissected very 

 many specimens of the two species haliotidca a.ud scutulum, mainly 

 with the object of testing specific determinations previously 

 based upon external characters. In this process it was deemed 

 sufficient for the purpose, to prove the presence or absence of 

 the flagellum, and it was not until some yellow variations of 

 T. haliotidca were examined more in detail, and with great care 

 that the writer noticed any deviation from the simple form of 

 penis figured by Lacaze-Duthiers, and later by Collinge, as 

 typical of the species. 



The deviation noted, recalled to mind the other figure given by 

 INIr. Collinge of a variation, but the structure not being the same, 

 the whole of the material available was carefully gone through 

 with a view to finding out the most general form. In every 

 specimen examined by the writer from some eighteen localities 

 dotted about Great Britain, a form of penis was discovered 

 differing from both of those figured by Mr. Collinge. In com- 

 paring the figure of the variation on Mr. Collinge's plate with 

 its description, it was noted that such a form was stated to 

 have been wrongly described and figured as typical, by Mr. 

 Ta}'lor. Upon turning to Mr. Taylor's paper, it was at once 

 obvious that the form found by the writer was very similar to 

 that described by the former as having " a tongue-like caecal 

 process." 



The structure found by the writer was more marked 



* Histoire dela Testacella, Arch, de Zool. Exper et Gen (2), vol. V., (1887), pi, xxxvi. 



