i86 



HA RD WICKE ' S S CIENCE- G SSJF. 



the neighbourhood of the London Road, St. 

 Leonard's-on-Sea, which was recorded in " The 

 Naturalist's World" for October 1886. This may 

 have been an imported or an escaped specimen. Be 

 the explanation what it may, one or two of these 

 lizards have been caught in England during the last 

 few years. — A. J. Field, 43 Medina Road, Finsbury 

 Fark, N. 



Abnormal Helix aspersa.— Mr. G. W. Mellors, 

 of Nottingham, has sent me some shells for inspection 

 which he collected at Tenby last year, and in the 

 batch occurs a specimen of Helix aspersa of an 

 abnormal appearance. Above the periphery of the 

 body-whorl there runs throughout its whole length a 

 roughened sulcus, devoid of periostracum, marked on 

 the inside of the whorl by a thickening of the nacre. 

 Where the sulcus ends at the peritreme the perio- 

 stracum is present, and the peritreme at this point 

 has a sinuous outline and shows evidence of repara- 

 tion. I attribute the abnormal appearance to fracture 

 not involving the mantle-edge in the injury ; and as 

 occurs in these cases the calcareous layers of the 

 shell are repaired by the animal, not the perio- 

 stracum, except at the peritreme. — J. IV. Williams, 

 Mitton, Stoiirport. 



The Darts of the Helicida. — It was with 

 some amazement that I read Mr. J. W. Williams' 

 remarks upon Mr. Standen's article on darts which 

 recently appeared in "Life Lore." I had read the 

 article with very considerable interest, and derived, 

 what I thought, a large amount of reliable informa- 

 tion therefrom ; now, however, Mr. W. seems to 

 throw doubt upon the whole matter. In the first 

 place he coolly designates the article as " fairly good 

 and accurate," and then goes on to say that, " so far 

 as I know, Mr. Standen's article is trustworthy, 

 except when he goes a little way from his subject 

 and mentions that some ' crystalline stylet ' is found 

 in the stomach of some snails, and he is afraid Mr. 

 Standen means Anodonta cygnea and other lamelli- 

 branchs, which can scarcely be classified as snails." 

 Permit me to observe that Mr. Standen has a reputa- 

 tion in this district for not only "accurate" but for 

 much more than fairly "good" work; after a re- 

 perusal of Mr. Standen's article, I can only come to 

 the conclusion, after carefully weighing Mr. W.'s 

 remarks, that either he has not read the article, or 

 else deliberately intends to misrepresent Mr. Standen, 

 who, I find, does not mention "snails " at all. What 

 he distinctly and clearly says is this : " There is an 

 organ known as the 'crystalline stylet,' found in or 

 near the stomach of certain slugs, which bears no 

 relation to the Helix dart, and must not be confounded 

 with it." From this, which is all that is said about 

 the matter, your readers can form their own opinion 

 as to how far Mr. Standen has gone away from his 

 subject ; the reference to the crystalline stylet is 

 perfectly appropriate, and I presume very few, even 



moderately informed conchologists, are ignorant that 

 such an organ is to be found in the stomach of various 

 slugs, e.g. Parmacella, and I venture to say that Mr. 

 Standen is too good a conchologist not to know the 

 difterence between a slug and an Anodon ! I will 

 only add that if there are any other observations of 

 Mr. Williams' on record, it is to be hoped they are 

 much more fairly good and accurate than this his 

 last one.— y. Hart, F.C.S. 



Variation in the Genus Arion. — Mr. J. W. 

 Williams has referred to me by name twice in his 

 article on " Variation in the Mollusca," published in 

 the July number of Science-Gossip ; and as in both 

 cases he is wrong as to matters of fact, I shall be glad 

 if you will allow me to point out how the facts really 

 stand. First, Mr. Williams has accused me of 

 describing a var. brunnea of Avion ater, when there 

 was already in existence the Arion brunnats of Leh- 

 mann. Evidently Mr. Williams has not given the 

 subject careful attention, or he would have known 

 that Lehmann's A. brunneus has nothing whatever 

 to do with A. ater at all, and is simply a synonym for 

 the bandless form of A. subfuscus, a quite different 

 species. I have before me Lehmann's original 

 description and figure (of anatomy), which were 

 published in the " Malakozoologische Blatter," 1862, 

 vol. ix., pages 165-167, and plate 3, fig. 2, and the 

 author's words and figure leave no doubt whatever as 

 to the relationship of the form he there described as 

 new, and in his opinion specifically distinct. Subse- 

 quent authors have relegated it to the synonymy of 

 A. sub/usctis. In the second place, I may say that I 

 have never described a var. pallesccns of Arion ater, 

 and whenever I have referred to that variety I have 

 simply been speaking of the long-known szx.pallcscens 

 of Moquin-Tandon. It is to be hoped that the author, 

 before making use of names in the manner in which 

 he has done in this case, will devote some care to 

 ascertaining that he is correct in his statements. — 

 William Denison Koebitck, Sunny Bank, Leeds. 



Variation in the Mollusca. — Mr. Roebuck 

 has written me regarding the two references I have 

 made to him in' the first part of my paper published 

 in these pages, on "Variation in the Mollusca, and 

 its probable Cause." These I wish in this note to 

 place in a good light. It seems, in the first place, 

 that I was under a decided misapprehension when I 

 stated that a var. pallescens had been described by 

 Mr. Roebuck, for in his letter he says: "I have 

 never described a var. pallescens of A. ater at all, 

 and that the old and well-known one of that name 

 described by Moquin is always what I refer to when 

 I use the name ^pallescens.' " In the second place, 

 with regard to what I have called Arion ater, var. 

 brunnea (Lehm.), I stated that the name had been 

 "appropriated" by Mr. Roebuck for an identical 

 form to what Lehmann had called Arion brunneus. 

 This, it seems, is wrong. Mr. Roebuck writes: "I 



