318 Mr. W. Thompson's Contributions to the Fauna of Ireland, 



possibly show that they should be brought together : C. scabrum 

 differs from it in having only twenty-six ribs, in the furrows being 

 equal and punctate, and in its exhibiting two obscure violet rays, 

 and having the beaks yellow ; but as my specimens were not seen in 

 a living state, stress need not be laid on the difference of colour. 



This species was obtained in three localities* nearly about the 

 same time. In October 1841 numbers of it, but mostly broken, were 

 found by Dr. Farran in the stomachs of sole (Solea vulgaris^ pur- 

 chased in Dublin market, and taken off our eastern coast ; in June 

 1842 Mr. Hyndman dredged a very few specimens from a depth of 

 50 fathoms, off the South Rock, coast of Down ; and specimens 

 which I have seen in Mr. Cuming's unequalled collection were sent 

 him by Dr. Loven in 1 842 as a species unknown to him, and which 

 had been obtained on the west coast of Sweden. It is named in 

 honour of this distinguished naturalist. 



■fAmphidesma intermedia, Thompson. Plate XIX. fig. 6. 



Shell oval-oblong, nearly equilateral, white with prismatic colours. 



Length 2 J lines ; breadth 4 ; thickness 1^ ; beaks almost central ; 

 shell nearly equilateral, rounded at each end, more particularly at 

 the posterior ; thin, semi-transparent, glossy, white with prismatic 

 hues. 



This species is intermediate in form or outline between Amph.priS' 

 maticum and A. Boysii, and also in general characters, but on the 

 whole may perhaps be said to approximate the latter the more nearly ; 

 its form however at once marks it as distinct from A. Boysii, than 

 which it has the beaks more central, is broader and more equilateral, 

 has the apex rather more marked and pointed, and is beautifully 

 iridescent inside and outside — the teeth do not present any marked 

 differential characters. 



* Should C. scabrum prove identical, in four localities — from Sweden to 

 Sicily — this has been discovered subsequent to the publication of Philippi's 

 first vol. in 1836, and is for the first time described in his second vol. which 

 appeared in 1844. 



fModioIa vestita, Philippi, Enum. Moll. Sicilise, vol. ii. p. 51. tab. 15. fig. 12 



(1844). 



This Modiola is included in my Report on the Invertebrata of Ireland, 

 but without any specific name being applied to it. A reference to the above 

 work as soon as it appeared showed that the Irish shell is the M. vestita, 

 known to Philippi only as found on the shore at Malta. 



In a letter from Mr. Alder written on the 1st of April 1844, it was men- 

 tioned that among shells lately sent from the Mediterranean to Mr. King, 

 Curator of the Newcastle Museum, were two specimens similar to the Irish 

 shell : they *' were imbedded in sponge, and one inch and one inch and a 

 quarter respectively in length, and a little thicker from being older shells, 

 but in all other respects the same." In May last I saw Modiolcs of this spe- 

 cies from the Mediterranean in Mr. Cuming's unrivalled collection. 



The only Irish specimen of this shell yet known was procured some years 

 ago at Youghal by Miss M. Ball. It is described and figured in the second 

 edition of Brown's * Illustrations,' p. 132. pi. 37. fig. 36, under the name of 

 Modiola Ballii. 



