COCKERELL AND COLLINGE : CHECK-LIST OF SLUGS. 5 



it requires some amount of faith to believe in the distinctness of 

 slugs which outwardly seem exactly alike. -^ While the value of 

 differences in the genitalia is undoubted, it does not seem proper to 

 assume that two forms are identical because the genitalia will not 

 serve to distinguish them. Among moths, it is known that in some 

 genera the species are easily separated by genitalia alone, while in 

 others undoubtedly distinct species have similar genital organs. 

 Nothing should be more strongly insisted upon than the impossibility 

 of applying the same tests of specific validity throughout series of 

 genera ; for characters that are generic in one place may not be 

 specific in another. 



All mutations are included, which will be contrary to the wish of 

 some malacologists. The writer has so often expressed his views 

 about varieties and mutations, that it would be superfluous to discuss 

 the subject here ; but it is represented that a check-list should above 

 all things be complete, and that it is better to include everything 

 than cripple the work by ignoring names at one's discretion — or 

 indiscretion — as it may be. x-\ll species are numbered consecutively, 

 and varieties and mutations are lettered. Synonyms are without 

 numbers or letters. Synonyms and names representing probable 

 synonyms are in old style antique. Thus Limax santorinns is given 

 a number because it cannot be definitely referred as a synonym, but 

 it is printed in italics because it is probably not a valid species. 

 A query (?) before a species or variety does not signify that it is 

 doubtful, but that its place in the classification is doubtful. Fossil 

 species are enclosed within square brackets [ ]. 



LIMACIDiE, Leach, 1S20; i. L. maximus, L. 



Turt. 1S31. parma, Brard, 1815. 



antiquorum (pars), Fer. 



LIMACIN/E, W. G. Binn., 1864. cinereus (pars), Miill. 



LIMAX, I.., 1758. cyreneus, Comp., 1837 (err.?). 



Limacias, Raf., 181 5. a. czernaevii, Kal. 



Eulimax, Moq. vulgaris, Moq. 



Stabilia, I'ini. fasciatus, Pic, 1840 (nee 



Limacella, Brard. Raz.). 



Limacellus, Brard, em Turt. i. bifasciatus, D. (X:M. 



Plecticolimax (err. ?). ii. quadrifasciatus, D.& M. 



Gestroa. iii- continuatus, I) & M. 



Chromolimax. b. fasciatus, Raz., 1789. 



Opilolimax. <• maculatus, Leach, 1820, ed. 



Cryptopelta (err. ?). <''i'iy, 1852. 



Subg. HEYNEMANNIA, Malm. krynickii, Kal., 185 1. 



Macroheynemannia, johnstoni, Moq., 1855. 



Simr., 1891. i. lilacinus, Roeb., 1884. 



•"■ It requires still more faith to believe in the distinctness of two slugs which anatomically are 

 identical, liecause the one is a different colour than the other — W. E. C. 



