128 PHOLADIDiE. 



land, is likewise given as a locality for the species in the 

 " Annals of Natural History," on the authority of two 

 specimens thus labelled in the Ordnance Museum ; and an 

 example, believed to have been dredged between Howth 

 and Lambay, was taken from a fishing-boat in Dublin Bay, 

 imbedded in a sandy conglomerate of shelly matter. (W. 

 Thompson, in Ann. N. H. vol. xiii. p. 434.) Few speci- 

 mens attain to greater dimensions than an inch and a half 

 in length, and about half that breadth. 



In Captain Brown's " Oonchological Illustrations" is a 

 Pholas sulcata* (p. 115, pi. 48, f. 17, 18), which more 

 nearly agrees with the young of this than with any of our 

 known British PJiolades. Its Scotch locality (Dunbar ; 

 in the collection of David Falconer, of Carlowrie,) is, how- 

 ever, against this supposition. 



* Since writing the above paragraph, we have received a letter from Captain 

 Brown, in which he assures us that this species, of which only a single valve was 

 found, is neither a fossil nor a variety of papyracea. We append, therefore, his 

 description, much regretting that the specimen is inaccessible to us. 



"■P. sulcata. Brown, 111. Conch. G. B. p. 115, pi. 48, f. 17, 18. 



" Oblong-ovate ; hinge-line nearly parallel ; almost equally rounded at both 

 extremities ; a thickening and slight flexure of the superior margin, extending to 

 the anterior side ; from the umbonal region emanate two obliquely longitudinal 

 narrow furrows, and terminate on the basal margin, at which point the shell is 

 longest ; iinterior to the sulci the surface is covered with close-set waved trans- 

 verse striaj, and the posterior side with irregular broken concentric strias ; external 

 surface of a yellowish or pale brown hue; inside smooth, white; a curved flat- 

 tened, tooth-like process under the umboncs, a small denticle at the central point 

 of the umbonal region, and an oblique longitudinal rib, corresponding to the ex- 

 ternal furrows." — Tliis shell teas found at Dtmhar, ami is in tJic collection of David 

 Falconer, Esq. of Carloivrie. 



