Book Notices. 497 



lends itself more readily than English does to terseness and 

 clearness of expression, as seen in European treatises on 

 Botany, in which it is used. Diligent field-work, he holds to 

 be the great desideratum for accuracy in systematic deter- 

 minations ; the accumulation and careful comparison of 

 specimens alone can secure true scientific results. 



R. C. 



Notes ox a Collection of Crataegus made in the 

 Province of Quebec near Montreal. — By Charles S. Sargent, 

 Reprinted from " Rhodora," Vol. 3, No. 28, April, 1901. 



New or Little Known North American Trees. III. — By 

 Charles S. Sargent. Reprinted from the " Botanical Gazette," 

 Vol. xxxi., April, 1901. 



The former of these pamphlets is of special interest to those 

 occupied with the Natural History of the District of Mont- 

 real. Anything bearing on trees or shrubs proceeding from 

 the pen of Professor Sargent, is sure to be of value ; and 

 when he writes of the native thorns of the continent, a 

 subject which he has made his own, his conclusions will be 

 received with the deference accorded to an expert. The first 

 thing we note, in connection with this paper, is the fact that 

 the collection of Crataegus on which the notes are based, was 

 made by Mr. J. G. Jack, a name honourably associated with 

 the plant life of this province. We are glad that Mr. Jack 

 does not forget his old home, although winning his bread 

 under another flag ; and that he patriotically desires to have 

 the flora of his native Chateauguay and its neighbourhood 

 made generally known. The next thing we have to remark is 

 the advance made in the views of the author of this mono- 

 graph. He now admits to the dignity of a species series of 

 plants which as late as 1889, when the 6th edition of " Gray's 

 Manual of the Botany of the Northern United States " was 

 issued, he is represented as classing as mere varieties; for the 

 list of the Crataegus species contained in that work, pp. 165-67, 

 is given as characterized by Prof. C. S. Sargent. This advance 

 movement is in obedience to the prevailing tendency among 

 men of science to multiply species; although there are some of 

 conservative temper to oppose it. A series of plants, separ- 

 ated from other members of its genus by a quality or qualities 

 easily discernible, constant, and perhaps functional, it is now 

 usual to erect into a species. Prof. Sargent has found such 



