TRANSACTIONS OP THE SECTIONS. Ill 



hennetti, Scitirus palmarmn, Athene bmma, Comcias indica, Pratincola caprata, 

 Passer {Gijmnoris)Jlavicullis, P. indicm, Ortijgornis pondiceriana, Acanthodacti/lus 

 cantoris, and Calotes versicolor. Several of these extend as far west as the head of 

 the Persian Gulf, tut they rarely occur above elevations of 3000 feet above the sea. 

 With the above are associated some animals hitherto only found in Baluchistan and 

 Sind, and a few forms previously only known from North-eastern Africa or Arabia. 

 The whole of Persia may thus be divided into three principal regions,— the forest 

 countries of Ghilan and Mazendaran on the Caspian, and probably the wooded slopes 

 on the eastern border of Mesopotamia, extending south to the neigbbourhood of Shi- 

 raz, the fauna of which is essentially European ; the plateau of Persia, wMch is 

 occupied by a mixture of Paloearctic and desert forms ; and Southern Persia with 

 Baluchistan; inhabited chiefly by Indian and desert types. 



Some BemarJcs on the, Mollusca of the Mediterranean. 

 By J. Gwr:sr Jeffreys, F.B.S. 



After noticing the numerous writers on this subject, &om Aristotle to modern 

 authors, Mr. Jefli-eys remarked that the Mediterranean had long been debatable 

 ground with respect to the division of the European seas into zoological pro- 

 vinces. He referred to ' The Natural History of the Eiu'opean Seas,' by the late 

 Professor Edward Forbes and Mr. Godwin- Austen, and said that he agreed vrith 

 tlie latter in his view that the Mediterranean is " a vast lateral expansion 

 of the Atlantic," and not only in its physical aspects, but in most of its 

 natural-history productions ; and he believed that the missing links would sooner 

 or later be discovered. The newest and most complete list of the Testaceous 

 Mollusca of the Mediterranean is that by the Marquis de Monterosato, which 

 gives 758 species. Mr. Jefii-eys proposed to deduct 31 of these species for probable 

 varieties, and to add 39 species from the ' Porcupine ' and ' Shearwater' expe- 

 ditions, making altogether 766 Testaceous or shell-bearing species. The Nudi- 

 branchs and other naked or shell-less Mollusca described by Philippi (33 species), 

 as well as the Cephalopoda described and figured by Verany (43 species), being 

 added to the Testaceous species, there results a total number of 842 Mediterranean 

 species. Of these no less than 622 species inhabit also the North Atlantic, so that 

 only 222 species are at present supposed to be peculiar to the Mediterranean. 

 Lists of the 39 and 222 species are subjoined ; and the author fully expected that 

 most if not all of those in the latter category would be hereafter found in the 

 North Atlantic. According to the author's work on 'British Conchology,'_ there 

 are 562 species in our own seas, exclusive of those dredged beyond the line of 

 soundings in the ' Lightning ' and ' Porcupine ' expeditions.^ One of the most 

 interesting results of the ' Porcupine' expeditions consisted in the discovery at 

 considerable depths of living species of Mollusca which had been previously known 

 as fossils only and were regarded as extinct. Many of these species occm- in the newer 

 Tertiary beds of Sicily, and a list of them is likewise subjoined. The author said 

 in conclusion :— " We all profess to study the great book of Nature. But before we 

 study we must be able to read ; and who can say that he has read a single page, 

 much less a whole chapter, of this mysterious volume ? The sole knowledge we 

 possess of the deep-sea Mollusca of the Mediterranean (those which inhabit depths 

 exceeding 500 fathoms) is derived from a few casts of the dredge made m the 

 ' Porcupine ' expedition of 1870. The space thus partially explored was not much 

 larger than this room, while the area of the Mediterranean contains many hundred 

 thousands of square miles. Let us therefore compare the extent of om- researches 

 in this small nook or oftset of the Atlantic with that of the work yet to be under- 

 taken throughout the almost boundless area of the mighty ocean ; and having made 

 the comparison let us reflect, and then humbly confess our ignorance." 



In repljang to questions, Mr. Jeffreys said that the Suez Canal might hereafter 

 lead to an interchange of the Mollusca ; but he was not satisfied that more than 

 one species {Ringicida awiculata) was common to the Mediterranean and the 

 Red Sea. 



