March io, 1892] 



NA TURE 



445 



Bone as compared with the zone of totality is more difficult to 

 account for. 



The Smithsonian Institution has printed a capital study of 

 the puma or American lion {Felis concolor of Linnaeus), by Mr. 

 F. W. Tnie. The author notes that the puma possesses in a 

 remarkable degree the power of adapting himself to varied sur- 

 roundings. The animal endures severe cold during the winter in 

 the Adirondack Mountains and other parts of the northern frontier 

 of the United States, and tracks his prey in the snow. He is 

 equally at home in the hot swamps and canebrakes along the 

 river-courses of the Southern States. In South America he in- 

 habits the treeless, grass-covered pampas as well as the forests. 

 In the Rocky Mountains, as Mr. True is informed by Mr. 

 William T. Hornaday, he ascends to the high altitudes in which 

 the mountain sheep are found. Mr. Livingston Stone saw tracks 

 of the puma on the summit of Mount Persephone in California, 

 at an elevation of 3000 feet. Similarly, Darwin states that he 

 saw the footprints of the puma on the Cordillera of Central Chili, 

 at an elevation of at least 10,000 feet. According to Tschudi, 

 the puma is found in Peru in the highest forests and even to 

 the snow-line. 



In his Report on the Royal Botanic Gardens, Trinidad, for 

 1890, just issued, Mr. J. H. Hart, the Superintendent, says 

 that, while on a journey to St. Vincent, in August 1890, he 

 discovered a form of Agave rigida. Mill., previously unknown 

 to West Indian floras. It produces a useful fibre, but appears 

 to be too short in the leaf to rival the variety known as Agave 

 rigida, var. sisalana, of Perrine. The same species has also 

 since been found in Barbados, and identified with the above. 

 "With nothing," says Mr. Hart, "is it more easy to make a 

 mistake than the various species of Agave, and special care 

 should be taken by growers for economical purposes to have 

 their plant identified by competent persons, before expending 

 large sums on cultivation. As an instance, I may mention that 

 the Coratoe of Jamaica was for long years popularly supposed 

 to be no other than the Tropical American Agave americana, 

 until an examination was made into its characteristics by Mr. 

 D. Morris when that gentleman was resident in Jamaica. The 

 same thing occurred in Trinidad. The Langue Boeuf of the 

 Bocas Islands was for many years supposed to be Agave vivipara, 

 Linn., but a plant sent to Kew from these Gardens proves it to 

 be the Mexican Agave polyacantha, Haw. A plant from St. 

 Lucia, recently received, shows characteristic points differing 

 from any of the above, though popularly supposed to be iden- 

 tical with our Bocas Island plant, and it may be found that 

 several unknown Agaves exist in the West Indies that have been 

 passed over by botanists from their similarity of growth to the 

 commonly known forms of the larger islands and mainland." 



An excellent series of "Museum Hand-books" is being 

 issued by the Manchester Museum, Owens College. A 

 •' General Guide to the Contents of the Museum " has been 

 prepared by Mr. W. E. Hoyle, Keeper of the Museum, and 

 Prof. Milnes Marshall has drawn up an "Outline Classification 

 of the Animal Kingdom," and a " Descriptive Catalogue of the 

 Embryological Models." 



We have received the tenth Annual Report of the U.S. 

 Geological Survey to the Secretary of the Interior, 1888-89, by 

 Mr. J. W. Powell, Director. It is divided into two parts, the 

 first relating to geology, the second to irrigation. 



Messrs. Gauthier-Villars have published a work en- 

 titled " Le9ons de Chimie," by Henri Gautier and Georges 

 Charpy. It is intended mainly for the use of students of 

 special mathematics. 



We learn from \\vt. Journal of Botany that the first pait will 

 shortly be issued by Messrs. Dulau and Co. of a new botanical 

 NO. I 167. VOL. 45] 



publication, to be called British Museum Phycological Memoirs, 

 edited by Mr. George Murray. It will be devoted exclusively 

 to original algological papers, the records of research carried on 

 in the Cryptogamic laboratory of the British Museum in Cromwell 

 Road, and is intended to be issued at about half-yearly intervals. 

 The first part will be illustrated by eight plates, and will contain, 

 among other articles, the description of a new order of Marine 

 Algae. 



Dr. Baillon's " Dictionnaire de Botanique," the publication 

 of which was commenced in 1869, is now completed. 



A NEW acid, chromosulphuric, possessing the composition 

 H2Cr2(S04)4, is described by M. Recoura in the current number 

 of the Comptes rendus. A short time ago the same chemist 

 obtained a remarkable isomeric form of chromic sulphate 

 Cr2(S04)3, which exhibited neither the reactions of a sulphate 

 nor of a salt of chromium. For instance, its solution yielded 

 no precipitate of barium sulphate with barium chloride. This 

 isomeric form of chromic sulphate is found to combine directly 

 with one equivalent of sulphuric acid or of a metallic sulphate to 

 produce the new acid, or a salt of it. Thus, when a solution 

 of zinc sulphate is mixed with a solution of the isomeric sulphate 

 of chromium in equivalent molecular proportion, zinc chromo- 

 sulphate is formed, ZnCr2(S04)4. The solution of this zinc salt 

 so obtained gives none of the reactions of sulphuric acid, nor 

 does it yield those of chromic acid, but it exhibits the usual 

 reactions of zinc salts ; hence it must be a zinc salt of a specific 

 acid, chromosulphuric. When the solutions of the new acid and 

 its salts are allowed to stand, they gradually decompose, and 

 barium chloride commences to precipitate barium sulphate, hence 

 they appear not to be very stable, but to decompose slowly into a 

 mixture of ordinary chromic sulphate and sulphuric acid or the 

 metallic sulphate. Boiling brings about the decomposition at 

 once. The acid itself has been obtained in the solid state, 

 combined with eleven molecules of water ; it is a green powder, 

 which is very hygroscopic, and rapidly deliquesces in moist air 

 but is quite permanent in a dry atmosphere. Its solution pos- 

 sesses a brilliant green colour when freshly prepared, but, upon 

 standing, changes to blue, and, after a few days, passes com- 

 pletely into a violet- coloured solution of ordinary chromic sul- 

 phate mixed with free sulphuric acid. The potassium salt has 

 also been obtained in the solid state, combined with four mole- 

 cules of water, as a green powder whose dilute solution yields 

 no precipitate with barium chloride, but at once gives the usual 

 potassium precipitates with platinic chloride and picric acid. 

 This salt also appears to be formed when chrome alum is de- 

 hydrated first for some time at 90°, and finally at 110°. The 

 sodium and ammonium salts have likewise been obtained, and 

 are found to resemble the potassium salt closely in their nature 

 and properties. 



The additions to the Zoological Society's Gardens during tne 

 past week include two Silver-backed Foxes {Canis chama), two 

 Leopard Tortoises ( Testudo pardalis) from South Africa, pre- 

 sented by Mr. C. Holmes ; a Vulpine Phalanger {Phaiangista 

 vulpina i ) from Australia, presented by Mr. W. J. C. P. Macey ; 

 a Ring-tailed Coati (Nasua rufa) from South America, pre- 

 sented by Miss M. Tew ; a Fallow Deer {Dama vulgaris 9 ), 

 British, presented by Mrs. Edith Hilder ; a Milky Eagle Owl 

 {Bubo lacteus) from Mashonaland, South Africa, presented by 

 Mr. E. A. Maund ; four Herring Gulls {Larus argentatus), a 

 Lesser Black-backed Gull {Larus fuscus), two Black-headed 

 Gulls {Larus ridihundus), a Jackdaw (Corvus monedula), a 

 Tawny Owl {Syrnium aluco), British, an Orange-cheeked Max- 

 bill {Estrelda inelpoda) from South Africa, two Hooded Finches 

 {Sperniestes cucullata) from West Africa, an Indian Silver-bill 

 {Munia vialabarica) from India, twelve Barbary Turtle Doves 

 ^Turtur risorius) from North Africa, presented by Mrs. Kate 



