248 NOTICES OP BOOKS AND MEMOIRS. 



with the adoption of Lindberg's arrangement, whereby instead of 

 the three now familiar terms, monoieDUS, dioicous, and synoicous, 



we now have six, namely : 



1. Synoicous, which retains its old signification. 



2. Paroicous, having the antheridia naked and axillary, as in 



Bryum nutans. 



3. Autoicous, equivalent for monoicous as usually understood, 

 having the fertile and barren flowers distinct, but upon the same 

 stem, as B. uliginosum. 



4. Heteroicous, with both synoicous and autoicous flowers on the 



plant, as B. pendulum. 



5. Dioicous, having the fertile and barren flowers on distinct 

 individuals, as in B. capillare and so many other mosses which are 

 but seldom found bearing fruit. 



6. Poloicous, having both barren and fertile flowers, both on 

 the same and on different plants — and this 6th section is again 

 divided into three subsections. Whether this change and multi- 

 plication of terms will be looked upon as anything but a doubtful 

 blessing by students remains to be seen. 



In regard to nomenclature the author, following Dr. Lindberg's 

 lead, adopts fully the principle of the right of priority, as already 

 he had done in various articles in this Journal and in his 

 * Sphagnacese.' This method has the sanction of authority, and it 

 is difficult to say anything in its depreciation : a principle is worth 

 nothing unless carried out regardless of convenience or consequence ; 

 but there will probably be regrets at the trouble involved in the 

 abolition or superseding of names grown familiar by many years 

 use, for the sake of others which have fallen altogether out of recol- 

 lection. It will be long a matter of difficulty and trouble to unlearn 

 what has taken years to learn, and Georgia will sound unwelcome 

 in the place of the long- accustomed Tetr aphis. 



These, however, are moot points, and in the presence of so 

 many excellencies as the work presents it is more agreeable to 

 leave them. The familiar names are given as synonyms, and col- 

 lectors may use their own discretion as to whether they will at 

 once adopt the new-old nomenclature, or wait till time shall have 

 given it sanction, bearing the inconvenience which reformations 

 must involve as patiently as they may. Apart from these ques- 

 tions the work will be found to furnish them with the fullest and 

 readiest means of studying and identifying the genera and species, 

 the habits and structure of mosses ; and we hope nothing will delay 

 the rapid progress and completion of a work of so much promise, 

 for which so much, and in whose depreciation so little, is to be said. 

 The large increase in the number of British species of mosses since 

 the publication of Wilson's < Bryologia/ five-and twenty years ago, 

 and the scarcity of that work now, have created a want which the 

 4 British Moss-Flora ' is exactly and thoroughly adapted to supply- 



