168 Scientific Intelligence. 



the seventh in Mexico and fifth in India; grasses are fifth in the 

 world and in Mexico, but only third in India. Descending in the 

 systematic scale to the lowest terms of the series, the differences 

 between the elements of the two Floras become greater and 

 greater until genera are reached; thus as Mr. Hemsley shows, 

 only 25 to 26 per cent, of these are common to the two regions. 

 As yet data do not suffice to ascertain the exact number of species 

 common to India and Mexico, but it may not exceed 600 of the 

 25,273 which is approximately the sum of the species of both 

 Floras." Sir Joseph does not discuss the nature or the origin of 

 these striking likenesses and unlikenesses, but passes in his com- 

 mentary to a brief account of what he conceives to be the pri- 

 mary Floras of the globe. He limits the primary botanical 

 divisions of the globe to two, the Tropical and the Temperate, 

 and for these primary divisions he suggests the name, Botanical 

 Empires. The regions " next in importance to the two primary 

 are in my view seven, — two north temperate, of the Eastern or 

 Old, and Western or New World, respectively ; two tropical, cor- 

 responding to the above ; and three south temperate (America, 

 Africa, and Australia)." For these regions he proposes the term 

 Kingdom. With regard to " the exact geographical limitations 

 of any of these seven botanical areas, such are possible only 

 where geographical features present insuperable obstacles to the 

 further spread of the plants that characterize them. Where two 

 are conterminous, there is always a neutral ground, often a very 

 broad one, and this neutral ground may itself present a Flora 

 which may be regarded as either tropical or temperate." 



Mr. Hemsley on the other hand, with the same statistics before 

 him, proposes a different division. He thinks it possesses certain 

 advantages over that suggested by Wallace for the distribution 

 of animals: — these regions are the following, — (1) Northern, (2) 

 Neotropical, (3) Palseotropical, (4) Andine, (5) Cape, (6) Austral- 

 ian. " The anomalous Sandwich Islands Flora and the fragment- 

 ary Antarctic Flora would be unattached in this as in the other." 



Mr. Hemsley has given in the appendix a very valuable account 

 of the distribution of the more prominent natural orders, and 

 closes his work by a recapitulation of the dominant features of 

 the Flora of Mexico and Central America, and remarks on its 

 probable derivation. To them we hope to recur later. G. l. g. 



3. A Hand-book of Cryptogamic Botany ; by Alfred W. 

 Bennett, M.A., B Sc, Lecturer on Botany at St. Thomas's Hos- 

 pital, and George Murray, Senior Assistant Dept. Botany Brit- 

 ish Museum. 472 pp., 12mo, with 378 illustrations. London, 

 1889. (London and New York: Longmans, Green &,Co.) — This 

 small Hand-book covers all departments of cryptogamic botany. 

 The parts on Vascular Cryptogams, Muscineae, Algse and Schizo- 

 phyceas are by Mr. Bennett, and those on Fungi, Mycetozoa and 

 Schizomycetes by Mr. Murray ; but the authors hold themselves 

 " severally responsible for the whole contents of the volume." 



This compact, well- printed volume contains a mass of details 

 on the different orders of cryptogams, which will make it a val- 



