MARSHALL: ADDITIONS TO "BRITISH CONCHOLOGY. 73 



with more rounded whorls and constant colour. I have not met with 

 it at Jersey, where the type is the prevalent form. It is well figured 

 in "Mollusques du Roussillon," and the types of Recluz are in our 

 National Collection. 



Lacuna. — Dr. Watson has pointed out in the ' Challenger' Report 

 (P- 579) tnat "^ ' s unfortunate that in 'British Conchology' the artist 

 has represented Lacuna (in the generic plate) with ciliated tentacles," 

 to which it has no claim. He also adds that "in his generic diagnosis 

 oi Lacuna, Jeffreys does not mention the epidermis." The canal and 

 umbilicus in all the British Lacuna: are variable quantities, even in 

 specimens from the same locality. Dr. Watson says he is "not aware 

 what relation this feature of the inner lip and umbilicus has to the 

 economy of the animal's life, but it would seem to be one of some 

 importance, possibly in connection with the eggs, and in that case it 

 is deserving of generic recognition." There seems to be no doubt 

 that in certain species of Helix, at any rate, advantage is taken of a 

 large and open umbilicus to afford shelter for the ova or young ; but 

 in those genera possessing a small and insignificant one it can serve 

 no purpose. Dr. Morch seems to have been the first to notice this 

 peculiar provision in the Endodonta (a widely-distributed section of 

 Helix). And Mr. Andrew Garrett, 1 in adopting LAbera as another 

 section of Helix for some species peculiar to the Society and Cook's 

 Islands, observed that they "are remarkable for their singular habit 

 of ovopositing into their cavernous umbilici." An interesting illus- 

 tration and some remarks on this habit are given in Science Gossip 

 (March, 1894). 



L. crassior Mont. — Of Jeffreys' two figures, the obverse one is a 

 subscalariform monstrosity, which is now and then met with ; the 

 other is the type. 



L. divaricata var. canalis Mont.— Horn coloured and thin. 

 Usually occurs at the mouths of rivers, and is analagous to L. puteolus 

 var. auricularis. 



Var. unifasciata Mont. — Extremely variable in shape and size. 

 Not always banded ; often uniform brown or white. 



Var. gracilior Mete. — Dornoch Frith. L 0-25, B. 0*15 inch. 

 A monstrosity of the type from Torbay has a double outer lip. 



L. puteolus Turt. — As in Phasianella, there are two forms every- 

 where, indicating the sexes. The female has a larger shell, with a 

 more globular body-whorl, a more prominent spire, and the base 

 obtusely pointed instead of rounded. In the male, the spire is 

 smaller and depressed, and the body-whorl is expanded laterally. All 



1 /. Ac. Philadelphia. 1881. 



