m E R 
ume 
1206 Scientific News. [November, 
and placed for half an hour in one per cent solution of gold and 
cadmium, being kept dark ; washed again in one per cent aqueous 
solution of formic acid, in which they were left twelve hours in 
the dark, then twelve in the light; finally kept in the dark in 
stronger formic acid for one day and preserved in glycerine. The 
fibers of such strips may easily be dissociated. l 
:0: 
SCIENTIFIC NEWS. borg 
— A review in the Nation of Bentham and Hooker's Genera of 
Plants, says: 3 
“Some idea of the progressive enlargement of the field may be 
had by a comparison of the number of genera characterized in 
these successive works. The phenerogamous genera of 
Linnzus, Gen. Pl. ed. t, A, D: 1737, WEEG. .scaveesere 
e “ s 
ed. 6, A. D. 1764, “ 4... asa 
Jussieu, “ A. D.. 1789, si yh secu 
Endlicher, “ A. De 1843, “ aboutssscce- 6400 
Bentham and Hooker, at A. D. 1883, $ neran EE 7585 
“If the last had been elaborated upon the scale of Endlicher, or 
with the idea of genera which is still common if not { a 
the number of genera would have amounted to at least ten pa | 
sand. An estimate of the number of known species of ai 
genus and higher group has been made throughout the pees 
rough approximation only, mentioning first the number in Me 
books, and the number to which, in the opinion of the auti ri 
these may probably be reduced by botanists who adhere to a 
Linnzan view of species; from which it appears that upon ~Y 
very strictest estimate their number, as now known p mere : 
the a ; 
of botanists. The five largest orders, as well for genera 35 
the orchid family in the list, will be a surprise to many. pense 
knew only a hundred species; five thousand is now “ae : 
estimate—about half as many as there are of Compost Tn both 
hold to their proportion of one-tenth of the arier its pe 
families every country and district is largely peculiar 1, 
cies and types. The far greater prominence of Com 
orchids is owing to the vast number of individuals 
their paucity in the latter.” 
— The British Association for the Advancement 7o 138: 
elected Lord Rauleigh president of the assoc Lorne, te 
Among the vice-presidents elected are the Marquis os Charles 
Marquis of Lansdowne, Sir John A. Macdonald, 9f =. Dr. 
Tupper, Sir Alexander Galt, the Right Hon. YT date of th 
Charles William Siemens and Professor Huxley. 
