HARDWICKE'S SCIENCE-GOSSIP. 



211 



and M. Baudrimont has obtained a number of such 

 plants in a fresh state, and determined the amount 

 of water and mineral matter they contained. In 

 all cases the ash bore a considerable proportion to 

 the organic matter, though often forming but a 

 small fraction of the entire plant. The largest 

 amount of organic matter was found in Aloes, and 

 the smallest in Cactus Peruvianus. The ash in the 

 latter was also smallest, and the percentage of 

 water greatest. 



Bacteria.— Prof. Cohu states that he finds, in 

 opposition to the statements of Wyman and Grace 

 Calvert, that the development of Bacteria in pre- 

 pared solutions is entirely prevented by exposing 

 them to a temperature of seventy-live to eighty 

 degrees, whilst a temperature of seventy degrees is 

 insaificient. Pencillium spores, on the contrary, 

 are not destroyed at the above temperature. 



Formation of Ozone by Flowers. — It has 

 been found that many essential oils, like those of 

 peppermint, turpentine, oil of cloves, lavender, 

 bergamot, aniseed, nutmeg, thyme, and others, 

 when in contact with the oxygen of the atmosphere 

 in presence of sunlight, develop very large quan- 

 tities of ozone. The oxidation of these oils is, in 

 fact, a very convenient source of ozone, as they, 

 even in small quantities, ozonize much oxygen. 

 The action is strongest in direct sunlight, far less 

 so in suffused daylight, and very weak or at an end 

 in tbe dark. The development of ozone which has 

 been begun in the light continues for a long time 

 in darkness. Eau de Cologne, hydromel, and other 

 aromatic tinctures, act in the same manner when 

 exposed to the sun's rays. Experiments made on 

 flowers with powerful perfumes, such as the nar- 

 cissus, hyacinth, heliotrope, mignonette, and others, 

 in closed vessels, prove that they also form ozone. 

 Those with fainter perfume produce less ozone, 

 those without scent none at all. Mantegazzn, who 

 has conducted these experiments, is of opinion that 

 this important source of ozone is of great hygienic 

 value for the purification of the air in marshy 

 districts. 



GEOLOGY. 



The Food of Plesiosaurus. — Professor Cope 

 recently exhibited vertebrte of a Plesiosaurus, and 

 those of a smaller species, found in close proximity, 

 the vertebrge column of the latter being immediately 

 below that of the Plesiosaurus, and in a reversed 

 position, as though it had been swallowed by the 

 larger reptile, which was over thirty feet in length. 

 The latter is a new species, and has been named 

 Plesiosaurus gulo. 



. New Tertiary Mammal, — A.t a recent meeting 

 of the American Philosophical Society, Professor 



Cope stated that the largest mammal of the Ameri- 

 can Eocene formations adjoining those of Wyoming 

 was the Bathmodoii radians, of about the size of a 

 rhinoceros. It was an odd-toed ungulate, with 

 peculiar dental character, which indicated a connec- 

 tion between different types of hoofed animals. He 

 also stated that the mammalian fauna of Wyoming 

 and Utah more nearly resembled that of the Paris 

 basin than any yet discovered in America, and that 

 it contained a still greater number of generalized 

 mammalian forms. 



Professor Agassiz's South American Expedi- 

 tion. — The evidences of glacial action, on a scale 

 so extensive as to more than suggest that the 

 southern hemisphere has undergone a similar 

 general glaciation to that of the northern, are being 

 abundantly brought to light by Professor Agassiz 

 and his coadjutors. The former states that glaciers 

 alone could have sculptured the physical geography 

 of the country into its present shape. Moreover 

 the general striation of the country is from the 

 south northwards. This glaciation has been traced 

 as far as the northern end of Chiloe island. The 

 professor believes that it occurred simultaneously 

 with the same phenomenon in the northern hemi- 

 sphere, and that, during the glacial period, the two 

 hemispheres were capped with a sheet of ice of 

 enormous thickness. In South America he has now 

 succeeded in tracing glaciation up to thirty-seven 

 degrees south latitude, on the Atlantic as well as on 

 the Pacific coast. The existing southern ice-fields, 

 especially those of Magellan, have, like those of 

 Switzerland, once had a much greater extension. 

 Ancient moraines abound in the South American 

 valleys, and in the Straits above-named. One was 

 found damming up a valley so as to form a lake- 

 Agassiz concludes by stating that, old hunter as he 

 is in this respect, his anticipations of finding drift 

 phenomena in South America have been realized on 

 a greater scale than he had dared to hope. 



Cave Deposits in France. — Milne-Edwards 

 has just made a communication to the Academy on 

 the Carnivora and Cheiroptera, of which the fossil 

 remains are found in the phosphate of lime deposits 

 at Caylux, Tregols, and Concots. He furtlier de- 

 scribes the jaw of a cat, which he names Pseude- 

 lurus Edwardsii, and another animal which is a 

 Ihik between the cats and the Mustelidce. At Tre- 

 gols is a breccia composed of the bones of bats. 



" Towards the close of the Post-tertiary period 

 the^.land of passage by which the plants and animals 

 migrated to Ireland broke up. This preceded the 

 last of the series of changes in the physical geo- 

 graphy of Britain, which comprised the separation 

 of the British area from the Continent, and ended in 

 the present distribution of land and water."— 7V?/^'.s 

 " Historical Geology '' 



