79 
Obione of Gertner. The total number of species enumerated 
is 847, arranged in 2 suborders, 7 tribes, and 46 genera. 
A Flora of North America, arranged according to the Natural System, by 
John Torrey and Asa Gray. Vol. i. parts 3 and 4. 
At pages 5 and 41 of the volume of this work for 1889, 
this important publication has been already noticed. Since 
that time two more parts, completing the first volume, have 
made their appearance. They contain the remainder of 
Leguminose, and all the orders as far as Loranthacezx inclu- 
sive, of DeCandolle’s Prodromus, embracing therefore some 
of the most extensive of the orders commonly cultivated in 
gardens. 
The work is so full of original and valuable matter that to 
make extracts is an endless labour ; all persons interested in 
the North American Flora will of necessity procure the book 
itself. The reviewer must confine himself to general ob- 
servations upon points to which special attention should be 
drawn. 
The authors have bestowed much pains upon extricating 
the entangled synonymy of garden plants long cultivated 
in European gardens, and the opportunity enjoyed by Dr. 
Gray of examining, when in Europe, the original authorities 
upon which numerous species have been founded, gave him 
such advantages as no previous American Botanist has ever 
ossessed, ‘That he has used such opportunities with profit 
will not be doubted by any one who knows his Botanical skill 
and peculiar aptitude for critical investigation. We are how- 
ever clearly of opinion that in reverting at all times to the first 
name that has been given to a particular species he occasion- 
ally sacrifices general convenience to chronological rigour. 
For instance, it appears that the name Crategus tomentosa 
was given by Linneeus to the plant now universally called 
C. p rifolia ; and consequently the former name is restored ; 
but surely this is precisely one of the cases where summum 
"us is summa injuria, for the effect of the alteration is to 
render the nomenclature of every writer upon American trees, 
with the solitary exception of Duroi, at variance with that of 
the work now in course of publication. Had Linnzus given 
such a description of his plant as would have enabled Bota- 
nists to know what he meant, the name of C. pyrifolia would 
not have been substituted; but he did no such thing; he 
