106 



GEOLOGICAL MEMOIRS. 



There are, from the Red Sea and its neighbourhood, no fresh- 

 water Bivalves, no Brachiopoda, only one Pteropod is mentioned 

 (Odontidium rugulosum), although I possess Hyalcea quadri- 

 dentata and H. longirostris from the same locality, and no naked 

 marine gasteropoda. 



Land and Fresh-water Gasteropoda. 

 Succinea Pfeifferi Ross. Helix lenticula Fer. 



Helix pisana Mull. 

 striata Drap. 



Patella casrulea L. 



lusitanica Gm. 

 tarentina Lam. 

 fragilis Ph. 

 Fissurella graeca L. 



costaria Desk. 

 rosea Lam. 

 Bulla striata Brg. 



truncata Adams. 

 Eulima polita L. 

 Chemnitzia elegantissima Mont. 

 Truncatella truncatula Drap. 

 Rissoa glabrata V. M'dhlf. 

 Natica olla M. de Serr. 



millepunctata Lam. 

 Nerita viridis L. 

 Ianthina bicolor Menke. 

 Haliotis tuberculata L. 

 Tornatella tornatilis L. 

 Trochus crenulatus Broc. 

 striatus L. 

 Adansonii Pay. 



Cephalopoda. 



Octopus vulgaris. 



Paludina rubens Menke. 

 thermalis L. 



Marine Gasteropoda. 



Trochus varius Gm. 

 Cerithium vulgatum Brg. 



mammillatum Riss. 



Lima Brg. 



perversum Brg. 

 Fasciolaria lignaria L. 

 Fusus corneus L. 



syracusanus L. 

 rostratus Olivi. 

 Murex trunculus L. 

 Tritonium variegatum Lam. 

 Ranella lanceolata Mke. 

 Dolium Galea L, 

 Buccinum variabile Ph. 



mutabile L. 



gibbosulum L. 

 Mitra lutescens Lam. 

 Marginella clandestina Broc. 



miliacea L. 



minuta P. S. 

 Cyprsea moneta L. 

 erosa L. 



On the whole, the following table exhibits the relative state of 

 the Red Sea and South Italian fauna. 





Red Sea 



Sicilian 



No. of Species 



Proportion of 



Species 





Species. 



Species. 



common. 



common to both. 



Marine Bivalves 



127 



187 



29 



or 23 per ct. of 



16 perct. 



Fresh- water do. 



5 



11 







Red Sea spec. 



of Sicil. 



Pteropoda 



3 



13 



1 





spec. 



Naked marine ^ 



23 



54 











Gasteropoda J 







Conchiferous do. do. 



248 



313 



44 



18 



14 „ 



Land and fresh- "1 

 water do. J 



30 



186 



5 



16 



2 „ 



Cephalopoda 



7 



15 



1 







Cirrhopoda 



10 



18 



3 





16 „ 



This result shows that the Red Sea fauna has a greater analogy 

 with that of the Mediterranean than the Senegal fauna. The 

 latter has 17, and the former 23 species of marine bivalves common 



