284 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



obscurus exists in great abundance, while the larger sharks 

 are not common. The Pleuronectidce were not met with at 

 all, with the exception of one species of Rhomboidichthys, 

 supposed to be new. During a violent southeast gale which 

 visited the islands in January last, hundreds of the smaller fish, 

 some hitherto unknown to the fishermen, were cast ashore, 

 including numerous specimens of Aulostoma coloratum. Mr. 

 Jones noticed material changes in the habitat and abun- 

 dance of certain marine mollusks, compared with observations 

 made some twenty years ago. Littorina muricata, which 

 used to occur in vast quantity on the shore rocks of the 

 south coast of the main island, proved to be not nearly so 

 numerous now ; while X. ziczac, which until lately was com- 

 paratively rare in that locality, is now quite common. Pec- 

 ten ziezae also, which w T as common about the sounds and in- 

 lets, is now confined to a few localities. Very few migratory 

 birds visited the Bermudas during the winter of 1873-4 a 

 strange occurrence, which may, however, be accounted for by 

 the absence of the usual northerly gales of that season. 



ABSENCE OF ANIMAL LIFE IX THE MEDITERRANEAN. 



Dr. William B. Carpenter, in attempting to explain the re- 

 markable absence of animal life in the deep waters of the Med- 

 iterranean, refers the cause, in the first place, to the muddy 

 condition of the bottom water, resulting from the minute par- 

 ticles brought down from the Nile and the Rhone, and dis- 

 seminated throuo-hout the w r hole bed of the sea. Nothing 

 appears to be more injurious than an extremely fine sediment 

 of this nature continually in the process of deposition, geo- 

 logical evidence showing clearly that the finest-grained sedi- 

 mentary deposits are usually almost destitute of resident ani- 

 mal life, the few fossils exhibited consisting almost exclusive- 

 lv of sharks' teeth, or the remains of other free swimming 

 animals that have died and sank to the bottom ; while in an- 

 other part of the same stratum, composed of coarse-grained 

 materials, life may prove to be quite abundant. 



Another condition in the Mediterranean, equally unfavora- 

 ble with this turbidity, if not more so, is the deficiency of 

 oxygen produced by the slow decomposition of the organic 

 matter brought down by the great rivers. 



According to determinations made by Dr. Carpenter in 1871, 



