12 DtJBLIN NATTTKAL HISTOEY SOCIETY. 



It has been recorded in the Dublin lists on the authority of Dr. Ball. 

 I find the observations of this gentleman with regard to our Dublin 

 species so correct,— in fact, in every instance but this having verified his 

 observations by specimens obtained by myself, — that, although a careful 

 search for this species in Dublin, on my own part, has been hitherto 

 unsuccessful, I yet feel great hesitation in contradicting the statement. 

 The fact of there being but a single specimen in his collection, so marked, 

 leaves room, however, for the surmise that there may have been some 

 mistake. In Ireland it has been recorded in Antrim (0. C), Dublin 

 Bay? (R. B.), vide ante, Hook Head (RB.), Cork? (C. C. S.), Valen- 

 tia Island, Tory Island ("W. T.) The specimen thus marked in J. V. 

 Thompson's collection is X tuherculata* 



The fact of the species having occurred on the north-east coast does 

 not militate against its being regarded as southern. Several other seem- 

 ingly southern, or, more probably, western species, are found to occur 

 along the eastern coast of the north of Ireland. In England, as far as 

 I find it recorded, the distribution of this species is southern. 



Xantho rivulosa. — Along with the last, a single specimen was found 

 under the stones near Renaune Point : it is a female, and half grown, 

 and exhibited the following distinctive characters, as contrasted with 

 Xantho florida, captured at the same place : — Front produced, directed 

 forwards, lamellar, leaded along its margin; pterygostomian regions 

 granulated (in X.florida, punctated) ; dentition of lateral edge. D. slightly 

 marked, yet distinct, E.N.T.S. ; (in X. florida D. nearly completely 

 obsolete) ; superior surface of carapace much flattened, posterior pairs of 

 legs hairy upon superior edges. The character of the double groove on 

 the movable finger is by no means a constant distinction, as it is found 

 in some young specimens of X. florida. 



This is undoubtedly a southern species. The only Irish specimen 

 heretofore known, and which I am, through the kindness of G. V. 

 Du Noyer, Esq., enabled to figure from the original sketch made in 1839, 

 and which is itself here exhibited through the kindness of the authorities 

 of the Museum of Irish Industry, was obtained at Portrush, 1839 (O.C.), 

 Hook Head (R.B.),t Valentia Island, 1856, Galway (Prof. MelviUe). 



* Xantho ttiberculata. — Among tlie collection of Crustacea purchased from J. V. 

 Thompson by the Eoyal College of Surgeons, Ireland, and by them presented to the 

 Royal Dublin Society, there is a mutilated specimen— marked in the Catalogue 

 No. 23, " I. Xantho Jloridus, imperfect" — which is either this or some closely allied 

 species. The absence of the hindlcgs prevent a positive opinion as to the species ; 

 but in the produced front and coarsely tuberculated hands, &c., it appears identical 

 with Bell's figure. I have noticed it here, as it appears to have escaped W. Thomp- 

 son's observation ; and it were exceedingly desirable if the occurrence of this south 

 British type on the Irish shores could be confirmed. It is singular that there is no 

 specimen of Xantho florida at all in the collection. I have been at pains to identify 

 tnis specimen as the actual specimen described in the Catalogue as above, and find 

 there cannot be any doubt as to its identity. 



t X. rivulosa. — Since the above paper was read, Dr. Robert Ball kindly afforded 

 me an opportunity of examining the fine collection of Irish Xanthos in the Univer- 

 sity Museum, Trinity College, and among a number collected at Hook Head , county 



