36 WEBB : BRITISH SPECIES OF TESTACELLA. 



A swelling (dilatation inferieure) appears upon the penis at about the 

 position occupied by the little caecum in British examples, and a lateral 

 retractor (muscle lateral) noted by Mr. Taylor and the writer but not 

 shown by Lacaze-Duthiers nor Collinge is figured. 



1858. Gassies and Fischer. — "Monographie du Genre Testacelle," 

 Actes Linn. Soc. Bordeaux, xxi., pi. I,, fig. 15. 



Mr. Taylor pointed out that this figure (apart of which is reproduced, 

 figure 4) though labelled viaugci, obviously belongs to haliotidca (a conclusion 

 independently arrived at by the writer), and also that on the authority of 

 these writers, Pollonera credited T. viaugei with a flagelhim. A lateral 

 retractor is indicated. 



•1889. Carlo Pollonera. — " Osservazione intoruoad alcune specie de 

 Testacella." Boll. Mus. Zool. Anat. Comp , Torino, iv., pi. i., figs. 2 and 3. 



The figure labelled T. diibia depicts a form of penis very much resembling 

 that given in illustration of the present paper (plate VI,, fig. i), while this 

 organ as given for T, halictidca more resembles that called a variation by Mr. 

 Collinge (reproduced in figure 8) in that it looks more like two swellings than 

 like a single one and an elbow. 



Signor Pollonera expresses his opinion that the form figured by 

 Lacaze-Duthiers belongs to some other species differing from and wrongly 

 determined as T. haliotidca ; this still, however, remains to be proved. Further, 

 he does not agree with Mr. Taylor's interpretation of Gassies and Fischer's 

 figure, giving as his reasons small points of difference that would be put down 

 by English malacologists as due to the individuality of the specimen or the 

 figurer. Signor Pollonera gives, however, an excellent figure of the genitalia 

 of T. maugei, of course without a ilagellum. 



The evidence then, leads towards there being a form of Testacella as 

 described by Lacaze-Duthiers and Collinge which differs from the more 

 generally distributed T. haliotidca in some important particulars which may 

 turn out to be of specific value. 



Testacella scutulum. 



In this species the writer has noticed that tlie retractor 

 muscle of the penis is as broad as the terminal portion of that 

 organ which is slightly constricted from the broader and pre- 

 ceeding part. 



The spermatheca is usually round (as figured by Mr, 

 Collinge), occasionally egg-shaped, but without, in the specimens 

 examined, the much swollen basal part to the duct. (Plate VI., 

 figure 2). The vagina is very long indeed. 

 Testacella maugei. 



The swollen basal part of the spermathecal duct is not 

 inclined to be globular, according to the writer's dissections, 

 but to be of an oval, gradually diminishing into the more ordi- 

 nary proportions of the duct at the extremities. The lateral 

 entry of the duct into the spermatheca was not noted. (Plate VI., 

 figure 3). 



