EEPORT ON THE GASTEROPODA. 587 



2. Rissoa (Alvania) deliciosa, Jeffreys. 



Rissoa deliciosa, Jeffreys, "Lightning" and "Porcupine" Moll., Proc. Zool. Soc. Loncl, 1884, p. 121, 

 sp. 27, pi. ix. fig. 7. 

 ,, „ Weinkauff, Conch. Cab. (ed. Kiister), p. 178, sp. 95, pi. xxiii. figs. 5, 6. 



Station 85. July 19, 1873. Lat. 28° 42' N., long. 18° 6' W. Off Palina, Canaries. 

 1125 fathoms. Volcanic mud. 



Station 122. September 10, 1873. Lat. 9° 5' S., long. 34° 50' W. Off Pernambuco. 

 350 fathoms. Red mud. 



Habitat. — North-east Atlantic, in from 72 to 1095 fathoms; Mediterranean, Algerine 

 coast, in from 5 to 2G6 fathoms (Jeffreys). 



Dr Gwyn Jeffreys considers the specimens from Station 85 as " allied to " his species, and those 

 from Station 122 as distinct from both it and those from Station 85. After examination of his 

 specimens, which he kindly sent me, I am still of the opinion that both sets of Challenger shells 

 belong to one species, and that species Rissoa deliciosa, Jeffr. They are much larger specimens, 

 with much fewer and stronger ribs and stronger spirals, and in these respects the specimens from 

 Pernambuco greatly surpass those from Palma, but the whole aspect of the shells gives one the 

 impression of their being well-thriven specimens, not distinct species. 



The Marquis of Monterosato (Nomenclatura, p. 60) claims Rissoa deliciosa, Jeffr., as a synonym 

 of his Alvania electa. On that point I am unable to speak, the Alvania electa being to me unknown, 

 but even if it be so, as the Marquis asserts, I am quite sure that his principles of classification would 

 prevent him admitting the Challenger shells into his species. Of course no one can object to a writer 

 following any system of classification he pleases, but unless his system commends itself to others, it 

 is impossible for them to follow or to quote him ; and if the system which animates the Nomenclatura 

 be but pushed a little further, each of us will soon have a distinct generic title for every single specimen 

 of a shell we possess, and the confusion of the Tower of Babel will be reproduced in Conchology. 



3. Rissoa similis, Scacchi. 



Rissoa similis, Scacchi, Catalogus Conch. Napol., 1836, p. 14. 



„ „ Philippi, Enumeratio, vol. ii. p. 124, sp. 5, pi. xxiii. fig. 5. 



„ ,, Schwartz v. Mohrenstern, Rissoa, p. 38, sp. 28, pi. iii. fig. 28. 



, t „ Weinkauff, Conch. Mittelmeer., vol. ii. p. 297. 



,, ,, Manzoni, Rissoa des Canaries, &c, Journ. de conch., 1868, vol. xvi. p. 248. 



,, ,, Aradas and Benoit, Conch. Mar. Sicil., p. 193, No. 513. 



„ „ Watson, Madeira Mollusks, Proc. Zool. Soc. Lond., 1873, p. 379, pi. xxxv. fig. 16. 



,, ,, Monterosato, Enumerazione, p. 23. 



„ (Apicularia) similis, Monterosato, Nomenclatura, p. 56. 



,, similis, Seguenza, Form. Terz. Calabria, pp. 268, 320, 355. 



„ . „ Jeffreys, "Lightning" and "Porcupine" Moll., Proc. Zool. Soc. Lond., 1884, p. 117, 



sp. 19. 



„ „ Weinkauff, Conch. Cab. (ed. Kiister), p. 117, sp. 16, pi. iii. figs. 15, 16. 



February 10, 1873. Tenerife. 78 fathoms. 

 Habitat. — Mediterranean, Madeira, and Canaries. 



