414 Miscellaneous. 
with the similarity of recent limpet shells which are secreted by 
widely different animals, it is almost inconceivable that the Silurian 
form should have any closely allied recent representative. The 
rhythmical manner in which the adductor scars of Tryblidiwm are 
arranged in pairs clearly indicates a peculiar disposition of the 
organs, which might indeed have paralleled in some particulars the 
organization of some of the Chitons of that ancient time. 
For the rest, many of the ancient limpets are represented by shells 
which might well have belonged to Lepeta or Acmea, yet of the 
relations of which, as in the case of many recent limpets, we are 
not permitted to arrive at any dogmatic opinion for want of the 
requisite data, a deficiency which, in the case of the fossils, must 
remain for ever unsupplied.—Proc. Acad. Nat. Sci. Philad. 1898, 
p. 285. 
On the Occurrence of Arion lusitanicus, Mab., in the British Isles, 
and Descriptions of Four new Varieties. By Water E, Cotiner, 
Mason College, Birmingham. 
Through the kindness of Mr. H. Burnley Rathborne, of Dublin, I 
have recently received some specimens of this interesting species of 
Arion, collected at Bevihenen, Bantry Bay, Ireland. 
Dr. Scharff, in his work upon the Irish slugs *, mentions a variety 
of A. empiricorum, Fér., in which the retractor muscles “ are 
attached quite close to the receptaculum and the upper portion of 
the oviduct;” this, I have previously stated, I consider to be 
A, lusitanicus, Mab. Some months ago I examined specimens from 
Ireland and compared them with continental examples, and felt 
sure that I was correct in assigning the former to this species. 1 
hope shortly to obtain further supplies of material, and will then 
describe in more detail the anatomy. References to the anatomy 
&c. are given by Pollonera t, Simroth §, and myself |j. 
Whilst recording this interesting addition to the fauna of the 
British Isles I take the opportunity of describing four new colour 
variations. 
Rufescens, var. nov. 
Whole of body a dark red. Sides of body bandless. Sent with 
type by Mr. Rathborne. 
Nigrescens, var. nov. 
Described from a black specimen sent with type by Mr. Rath- 
borne. I would, however, suggest that the name should include all 
* Trans. Roy. Dublin Soc. 1891, ser. 2, vol. iv. p. 589. 
+ ‘The Conchologist,’ 1893, vol. ii. p. 7. 
t Atti Acc. Sci. di Torino, 1889, pp. 405, 406, pl. ix. figs. 1-6; also 
Boll. d. Mus. Zool. ed Anat. comp. Torino, 1890, vol. v. no. 87. 
§ Die Nachtschnecken d. Port. Fauna, 1891. 
|| ‘The Conchologist,’ 1892, vol. ii. p. 116. 
