COCKERELL AND COLLINGE : CHECK-LIST OF SLUGS. 207 



Therefore, since we know that rufus was meant to include 

 the red empiricorum, and only doubt whether it may not 

 have included something different in " sub-rufus" it seems 

 but reasonable to use rufus, L., in preference to Ferussac's 

 title. 



Furthermore, even if we set aside the Linnean name as 

 unavailable, empiricorum falls before L. luteus, Raz., 1879, 

 and L. succineus, Mull., 1774 — which represents its yellow 

 variety. 



366 b. a/bus. First described by Muller as L. a/bus margine lutes 

 in 1763, but first named alius in accordance with the 

 modern system of nomenclature, by Linne, Syst. A r at. 

 ed. xii. (1767). I follow Pollonera in referring this to 

 ater proper. 



366 b. i-iv. These four forms named by Moquin-Tandon ought to 

 be such as are found in France, and therefore belonging 

 to rufus {empiricorum). But they exactly correspond both 

 in character and the order in which they are given with 

 Midler's four varieties (Verm. Hist., 1774, p. 4) of his a/bus, 

 so they may be taken as based on the Miillerian descrip- 

 tions, and not on specimens examined by Moquin-Tandon, 



366 f marginatus. Miss Esmark (/. of Conch., 181 2, p. 102) records 



var. marginatus, Moq., from Norway. If the Scandinavian 

 slug is held distinct from the French one, this will be 

 a variety of it, coloured like marginatus. It is to be 

 observed, however, that Pollonero admits that some Scandi- 

 navian examples are veritable empiricorum, as distinct from 

 ater. (Arionidae, p. 5.) 



367 a. johnstonii. So spelled by its author. 



367 b. Gray {Cat. Pulm. B. M., 1885, p. 54) quotes Limax ruber, 

 Drap. I cannot now consult Draparnaud's work, but if 

 the present variety was named ruber, of course lamarckii 

 must fall. 



367/ luteus. I prefer this name, because Muller says of succineus, 

 " Rufo-juscus vel succini colon's " — thus including red- 

 brown forms. I have been doubtful whether to cite the 

 synonym flavescens, as it is by chance that Ferussac uses 

 a single term for the variety— as may be seen by comparison 

 with his other citations of varieties, which are evidently 

 intended as descriptive. The figure of flavescens is too red 

 for luteus as strictly defined. 



367/ ii. ferussackii. So spelled by its author. This name and 

 the two placed as synonyms of it belong to a greenish 



