314 Mr. J. Walton on the genus Omias. 



longitudinally by oblique striae wbich diverge from the hinge to 

 the margin. There is a strongly developed flexuosity at the an- 

 terior extremity which teniiinates in rather an acute edge. Hinge 

 as in V, Pullastra. Breadth 1| inch ; length 1 inch. 



A single valve of this size occurred to me at Lerwick ; a small 

 live specimen at Deal Voe in the Shetlands ; and a still smaller 

 specimen was found by Mr. Barlee in Loch Fyne. 



It has a considerable resemblance to V. Pullastra, but it differs 

 in the peculiar obliquity of its form as well as its greater breadth 

 and other particulars. 



Astarte crebricostata, Forbes in Ann. Nat. Hist. vol. xix. p. 98. 

 Skye, but only single valves were found. 



Many specimens of Astarte were extremely difficult, if possible, 

 to be distinguished specifically, and the variety of form in this 

 genus is very puzzling. I am quite satisfied that the crenulation 

 of the margin is not a specifically distinctive character ; nor the 

 number of ribs, nor the form, much less the size or colour. With 

 respect to size, I may observe that specimens of A. compressa 

 measured more than three-quarters of an inch in diameter. 



Psammobia (?) plicata. Mytilus plicatus, Mont. Suppl. p. 70 ; 

 Laskey in Wern. Mem. pi. 8. f. 2. Two single valves of this cu- 

 rious shell were found by us in fifty fathoms off Skye. Mr. Han- 

 ley had previously taken it at Ryde. 



It has much the aspect of a Panopcea. 



Psammobia costulata. 



Psammobia strigillata. Skye. 



Corbula (?) granulata, Nyst, Belg. Foss. jp. 71. pi. 2. f. 6. Tel- 

 Una polygona, Mont.? I dredged one (live) specimen of this 

 curious shell in fifty fathoms off Skye. 



NecEra abbreviata, Forbes. Between seventy and eighty spe- 

 cimens of this shell were procured by Mr. Barlee in Loch Fyne. 



Many other extremely rare and interesting shells occurred, but 

 I have already I fear trespassed too long on the columns of this 

 month's ' Annals.' 



XXXIV. — Notes on the genus of Insects Omias, with descriptions 

 of new species. By John Walton, F.L.S. 



Fam. CUBCULIONIDJE. 

 Genus Omias, Germ, olim, Schonh., Latr., Dej., Sturm. 

 Thylacites [Brachysomus), Schonh. olim. 

 Otiorhynchus, Brachysomus, Steph. 

 Char. Gen. "iVntennse moderate, either slight or rather stout; 

 scape generally longer than the head, more or less curved, to- 

 wards the apex incrassated ; first and second joints of the funi- 



