202 DR. H. DOHRN ON NEW SHELLS. [JunC 24, 



to suppose they had been prepared by the same hand. I will men- 

 tion two remarkable cases as illustrations. A well-known barrier- 

 reef extends some hundreds of miles along the north-east coast of 

 Australia; its southern limit is near Moreton Bay ; and a reference to 

 Maury's Chart shows this to be the precise point at which a cold cur- 

 rent from the South Pole meets the warm equatorial current from the 

 east. Again, it appears somewhat remarkable that along the whole 

 western coast of North and South America no vestige of coral has 

 been found. Mr. H. Cuming informs me that he has dredged in 

 vain for specimens of these characteristic tropical productions in the 

 Bay of Panama and at the Galapagos ; but the chart shows that 

 cold currents from the north and south sweep the whole western 

 coasts of America, meeting at the Equator, and then turning away 

 into the Pacific, where, under a vertical sun, the water soon becomes 

 warm enough for the growth of the various coral-reefs scattered 

 about in that ocean. Fresh water and sediment of any kind being 

 present act as fatal barriers to the growth of coral ; and to these 

 causes may generally be traced gaps in reefs, and waste places of 

 limited extent in those seas which especially abound in corals. Dana 

 has recognized the effect of warm and cold currents in the general 

 distribution of corals throughout the warmer seas ; and the fact of 

 the same influences being at work, and easily recognized, in the 

 waters surrounding the British Islands appears sufficiently interest- 

 ing to justify me in bringing the subject before this Society. 



6. Note on the Size of a Seal at the time of Birth. 

 By Dr. J. E. Gray. 



We have received from the Zoological Gardens the body of a 

 Ringed Seal {Callocephalus fcetidus), that had died soon after its 

 birth. It was entirely covered with closely set, well-developed fur 

 of a silver-grey colour, being rather browner on the upper surface. 

 It is 2 feet 8 inches long, from the tip of the nose to the end of tail ; 

 the fore paws are 6, and the hinder 8 inches long, and the latter are 

 7 inches wide when expanded. The webs of the feet are covered 

 with hair, and the claws are well developed and black. The whiskers 

 are white, well developed, and slightly waved. 



7. Descriptions of New Shells. By Dr. H. Dohrn. 



1. CaTAULUS BLANFORDI. 



Testa subperforata, ovato-fusiformis, solida, confertim striata, 

 parum nitens, rufa ; spira convexo-turrita, apice obtusiusculo ; 

 anfr. 9, convexiusculi, ultimus attenuatus, antice subascendens ; 

 carina umbilicalis compressa, valida, antice vix dilatata ; pe- 

 riomphalum angustumy costulato-striatwn ; apertnra subcircu- 

 laris ; peristomium aurantiaco-fuscum, incrassatum, valde ex- 

 pansum, rejlexum, ad anfractum peiiultinmm angustatum, mar- 



