110 GEOLOGICAL MEMOIRS. 



species common to the Antilles and the Mediterranean is unex- 

 pectedly large. 



I will take this opportunity of correcting an error into which 

 D'Orbigny has fallen, before the mischief spreads further. M. 

 d'Orbigny observes, " Nous reunissons dans la famille des Tro- 

 choides les Mollusques gasteropodes, dont le principal caractere est, 

 d'avoir le dessus du pied pourvu lateralement des filets tentaculi- 

 formes plus ou moins nombreux. Nous les divisons ainsi qu'il 

 suit : — 



{Trochus 

 oolanum 

 Delphmula 

 Phorus ? 

 Des appendices a la base interne des tentacules, un f Turbo 



opercule pierreux |_ Phasianella" 



The truth of the matter is, that Trochus and the other genera 

 with a horny operculum exhibit the " appendices a la base in- 

 terne des tentacules" quite as well, and of as large a size, as 

 Turbo and Phasianella ; and if M. d'Orbigny thinks this is not the 

 case, he cannot have observed the animal properly. I have found 

 it very beautifully shown in all the fifteen species of Trochus of 

 which I have either drawn the living animal, or preserved it in 

 spirits ; and I can, therefore, only conclude that this statement of 

 D'Orbigny, and Quoy and Gaimard, is the result of imperfect ob- 

 servation. 



9. Comparison of the Fauna of the West Coast of New Holland 

 with that of South Italy. 



If we refer to the catalogue of 260 species of Mollusca collected 

 by Preiss on the west coast of New Holland, and described by 

 Menke in the " Specimen Molluscorum Novse Hollandise," we 

 shall find the following species, which also appear in the Medi- 

 terranean. 



Lutraria solenoides Lam. Succinea oblonga Drap. 



Mactra helvacea Chemn. Paludina thermalis L. 



Area tetragona Poll. Mitra lutescens Lam. 



Modiola lithophaga L. Cyprasa annulus L. 

 Lima squamosa Lam. moneta L. 



Bulla striata Brg. J 



