KEPOKT ON THE GASTEROPODA. 615 



1. Rissoina chesnelii (Michaud). 



Rissoa chesnelii, Michaud, Lcs Rissoa (2d ed.), p. 17, sp. 12, single plate, figs. 23, 24 (published July 

 12, 1830). 



„ ,, Michaud, Ann. Soc. Linn. Lyon, 1836, voL i. 



„ „ Potiez and Michaud, MolL Gallerie Douai, vol. i. p. 267, sp. 6. 



„ ,, Lamarck, Anim. s. vert. (ed. Desh.), vol. viii. p. 483, sp. 38. 



„ scalarella, C. E. Adams, Proc. Bost. Soc. Nat. Hist., 1845, vol. ii. p. 6. 



„ catesbyana, d'Orbigny, Moll. Cuba, 1853, vol. ii. p. 24, pi. xii. figs. 1-3. 

 Rissoina catesbyana, Fischer, Coq. Guadaloupe, Revue coloniale, 1857, p. 16, sp. 1. 

 Rissoina chesneli, Schwartz von Mohrenstern, Monog. Rissoina, p. 73, pL v. figs. 38, 39. 

 Rissoa catesbyana, Reeve, Conch. Icon., vol. xx. pL x. fig. 94. 



„ chesneli, Reeve, Conch. Icon., vol. xx. pi. x. fig. 89 

 Rissoina chesneli, v. Martens, Moll. Mauritius, &c, p. 285. 



„ „ Weinkauff, Conch. Cab. (ed. Kiister), p. 11, sp. 7, pL iv. figs. 19-21. 



Station 24. March 25, 1873. Lat. 18° 38' 30" N., long. 65° 5' 30" W. Off Culebra 

 Island, West Indies. 390 fathoms. Pteropod ooze. 



Habitat. — West Indies (Michaud) ; Jamaica (Adams) ; Mauritius and all the Antilles 

 (Schwartz v. Mohrenstern) ; Ceylon, Nicobars, and the Malay Archipelago (v. Martens). 



I have given the habitat of this species as the writers who may be supposed well informed have 

 stated it. That they are correct I cannot believe, the less so when in Baron Schwartz von Mohren- 

 stern's monograph on the genns we find the following : — 



Rissoina Burdigalensis (d'Orbigny), a fossil from Bordeaux, Northern Italy, and Vienna ; lives at Mauritius, 



p. 51. (Professor v. Martens puts a query to this, p. 284.) 

 Rissoina costata, A. Adams, living in Peru, is also said to live on the Philippines (while Deshayes attributes 



it to Reunion, and v. Martens to the islands of the Malay Archipelago, the Nicobars, and Ceylon). 

 Rissoina angula (C. B. Adams), a Jamaican species ; is said to live also in the Red Sea, and at Mauritius 



(a fact which v. Martens queries, p. 285). 

 Rissoina scalariformis (C. B. Adams), a Panama species, lives at Mauritius (and is further ascribed by 



v. Martens to the Red Sea and Polynesia). 

 Rissoina pusilla (Brocchi), a Subapennine fossil ; is ascribed to Mauritius and the Sandwich Islands. 

 „ conifera, Montague, a West Indian species ; is ascribed to Mauritius (a fact v. Martens queries). 

 „ Bryerea (Mont.), a West Indian species ; is ascribed to Mauritius (a fact queried by v. Martens). 

 ,, reticulata, Sowerby, the same. 



,, decussata (Mont.), a West Indian species ; is attributed to Panama, the Mediterranean, the East 

 Indies, and fossil to Rhodes, Sicily, Corinth, Vienna, and Bordeaux. 

 Rissoina cancellata (Philippi), a Cuban species ; is ascribed to Bolivia and the Philippines. 



These are statements so very remarkable, especially when taken in the aggregate, in reference to 

 a shallow-water genus, not, like the Tritons, given to wandering in its embryonic state, that they 

 call for the very fullest and most severe investigation, which, unfortunately, Baron Schwartz von 

 Mohrenstern has not given them, being content to speak vaguely of sea-currents from the Ant- 

 arctic Ocean as explaining their distribution. Professor v. Martens was not called on, by the nature 

 of his work, to discuss them, and has been content to guard himself by some marks of interrogation, 

 but it is obvious that the whole matter must yet be subjected to very full revision before such facts 

 ot distribution can be accepted. 



