Mr. W. Clark on the British Trochus Cutlevianus. 193 



Cutlerianus, at least to the extent of being an original one ; I 

 therefore beg you to allow me a small space in your valuable 

 Journal to defend my claim of being the author who first 

 introduced this species to the notice of naturalists. As ten years 

 have elapsed, I venture to bring to recollection that I originally 

 described the shell and its animal as a typical Trochus, pre- 

 viously misnamed a ? Skenea, which is a mere discoid Rissoa. 

 My description appeared in the 'Annals' for 1849, 2nd series, 

 vol. iv. p. 424; and in the 'British Mollusca/ vol. iii. p. 163, 

 and vol. iv. p. 270. 



As far as I am concerned, I should not have interfered in the 

 present matter; but Miss Cutler, an eminent naturalist, having 

 honoured me by accepting the dedication of this new species, I 

 am bound to maintain her undoubted title to the appellation of 

 Trochus Cutlerianus. 



Mr. Jeffreys, in his " Gleanings," in the ' Annals,' 3rd series, 

 vol. ii. p. 125, observes, — " M. exilis. Trochus exilis, Philippi, 

 vol. ii. p. 156, pi. 25. fig. 15. Skenea Cutleriana, Brit. Moll, 

 vol. iii. p. 164, and {Trochus) vol. iv. p. 270. In dredged sand 

 from Skye and Guernsey ; and Mr. M'Andrew has it from the 

 Mediterranean. A specimen, larger than usual, confirms the 

 idea I entertained from the first, that this is Philippics species." 

 Mr. Jeffreys only proves by this, that my T. Cutlerianus, which I 

 described as a new species ten years ago, has been found in 

 Skye, Guernsey, and ni the Mediterranean. The other part of 

 Mr. Jeffreys's notice only presents one datura — that a larger spe- 

 cimen than usual (of what ?) confirms him in the idea that Skenea 

 Cutleriana is Philippi's species, which itself rests on the founda- 

 tion of a single fossil : I quote Philippi's words, " Panormi in 

 calcareo specimen inveni." I ask, can this meagre exposition 

 be sufficient to upset my discovery, and prove that Philippi's 

 T. exilis is my T. Cutlerianus"^. But I proceed to show that 

 Mr. Jeffreys's opinion is erroneous, and that the two species are 

 distinct. 



I will now consider Philippi's text and figures of T. exilis in 

 comparison with T. Cutlerianus ; and it is fortunate he has given 

 a greatly enlarged figure, in addition to that of the natural size, 

 to exhibit the minutiae and accurate contour and form of his 

 shell. The pattern figure represents a globose and subconic shell, 

 having its axial and transverse diameter of much the same length, 

 showing /I'e volutions — that being the number stated by Philippi 

 in his text ; my British shell, of which I have taken many hun- 

 dreds, and have now in my collection sixty live, perfect, and 

 operculated specimens, has barely three volutions, which is the 

 normal number that stamps the adult shell. This difference is 

 so important and overwhelming a character as to be conclusive 



Ann. S^' Mac/. N. Hist. Ser. 3. Vol. in. 13 



