with descriptions of some new species of Invertebrata. 315 



Volvaria subcylindrica, Brown, Illus. Conch, p. 3. pi. 19. figs. 19, 

 20; 2nd edit.— pi. 38. f. 19,20; 1st edit. 



Among the Bundoran shells was one on which Mr. Alder made 

 the following remarks : " Capt. Brown's Volv. subcylindrica agrees 

 with it in outline, but he describes the species as smooth, while this 

 shell has both longitudinal ridges of growth and transverse strise. 

 The latter however are very faint, and in a worn shell neither of 

 them might be visible. I am inclined therefore to consider them the 

 same, but leave it to your own judgement to decide the question." 

 To the better judgement of Mr. Alder I prefer to leave it ; his know- 

 ledge too of the British marine Mollusca is very complete, whilst 

 mine is very superficial, and must remain so, my eyes being now 

 unable without injury to bear even the lowest magnifying powers .- 

 But that my friends kindly " lend me their eyes," I could not include 

 the minute species. All that Capt. Brown says of the locality of this 

 shell is — •' discovered at Dunbar by General Bingham." 



Rissoa costulata, Risso, Alder in Ann. Nat. Hist. vol. xiii. p. 324. 



pi. 8. figs. 8, 9, May and June (figures) 1844. 



When looking over the collection of Mr. Alder in October last, 

 he pointed out a specimen of this shell which had been given him by 

 Dr. Farran of Dublin, who procured it at Roundstone on the Gal- 

 way coast. 



The specimens described in the * Annals ' were from Torbay, De- 

 vonshire. 



^' Rissoa Warreni, Thompson. Plate XIX. fig. 4. 



On my submitting this species and the following (which I could 

 not find described) to Mr. Alder's opinion, he believed them to be 

 new, and before returning the specimens, wrote descriptions and 

 made drawings of them for his own guidance. Having offered to copy 

 these for my use if desired, I gladly availed myself of the proffered 

 kindness, feeling well-satisfied that the descriptions would be better 

 than any drawn up by myself, and that the figures would be most 

 faithful. 



Rissoa Warreni. — " Shell slender, tapering, thin, transparent yel- 

 lowish white, with six much rounded and deeply divided whorls ter- 

 minating in a rather fine point, the nucleus sunk in the apex. Aper- 

 ture oblong-oval : outer lip thin, without rib : inner lip not reflected, 

 but having a deep umbilicus behind it. The shell is slightly wrinkled 

 by the lines of growth, and is delicately striated spirally ; the striae 

 can only be seen with a good magnifier, and are most distinctly ob- 

 servable at the base. There are also some faint indications of small 

 obsolete ribs on the middle whorls. Length two-tenths of an inch ; 

 breadth one-twelfth." 



Two specimens were found at Portmarnock (Dublin coast) by 

 T. W. Warren, Esq. 



•fOdostomia crassa, Thompson. Plate XIX. fig. 5. 

 Of this shell a single specimen was sent me from Roundstone, 



Z2 



