1884.] * LIGHTNING' AND 'PORCUPINE ' EXPEDITIONS. 1 29 



varieties of H. ventrosa) he criticizes Kiister for placing among the 

 HydrobuB Pennant's Turbo ulva;, contending that it is " une veri- 

 table Assiminea." I have already shown in ' British Conchology,' 

 vol. v. p. 208, and in the foregoing notice of II. ulvte, that 

 A. cjallica of Paladilhe is the typical form of the above species. 



Family X. Paludinid^;. 



Bithynia rubens, Menke. 



Paludina rubens, Menke in Chemn.-Kiist. pi. 9. f. 27-29. 



'Porcupine' Exp. 1870: Med. St. 51. Two small specimens, 

 which had been probably carried out to sea from a freshwater river 

 or stream and deposited in 1415 fathoms. 



Distribution. Sicily, Algiers (coll. Weinkauff.). 



Family XI. HETEROPHROSYNiDiE. 

 / Barleeia rubra, Montagu. 



Turbo ruber, Mont. Test. Br. p. 320. 



B. rubra, B. C. iv. p. 56, pi. I. f. 2; v. p. 209, pi. hdx. f. 4. 



'Porcupine' Exp. 1870: Atl. St. Gibraltar B. ; Med. 50, Ben- 

 zert Boad. 



Distribution. Hellen in Bergensfiord (Friele), northern and 

 western coasts of Ireland, southern counties of England, N. and W. 

 coasts of France and Spain, Mediterranean and Adriatic, Canaries 

 and Madeira (McAndrew), C. Verd I. (Rochebrune), off Pernam- 

 buco (' Challenger ' Exp.) ! ; littoral and laminarian zones to 120 

 fms., the greater depths being probably accidental. I distrust the 

 recorded localities in Scotland, the North of England, and South 

 Wales. 



Fossil. Pliocene : Central and Southern Italy. Post-tertiary : 

 Leghorn. 



The only noticeable synonym is Rissoa fulva of Michaud. 



Family XII. Skeneid^e. 



>.-• Homalogyra densicostata V, Jeffreys. (Plate X. fig. 1.) 



Shell somewhat resembling in shape Planorbis trivolvis of 

 Say, rather thin, semitransparent, and glossy : sculpture, extremely 

 numerous and close-set striae in the earlier and middle stages of 

 growth, which ultimately disappear and become microscopic lines ; 

 the upper part of the periphery as well as the base of the shell 

 are encircled by a sharp keel which intersects the spiral striae : colour 

 whitish : spire deeply sunk on both sides : whorls 4, compactly 

 coiled ; the last is swollen and disproportionately large ; the others 

 rapidly decrease in size : suture narrow but excavated : mouth 

 horseshoe-shaped, with a thin edge, and expanding outwards : 

 umbilicus very wide and open, completely exposing the spire on 

 each side. L. 0-05. B. 0-075. 



1 Closely ribbed. 

 Proc. Zool. Soc— 1884, No. IX. 9 



