346 REVIEWS INTRODUCTION TO CRYPTOGAMIC BOTANY. 



them together under the name Mtcetales. This 13 a consequence 

 of the theory that all divisions of one name must be of equaV value 

 and equally related to each other, a theory altogether at variance 

 with well-known facts. The arrangement of Acrogens is as follows: 

 " Spores or nucules solitary. Chabaceales, an alliance consisting 

 of the order Characece alone. 



Spores numerous, giving rise to a plant which produces one or 

 more successive sets of fructifying archegonia : — MtrscALES, § 1, 

 without a peristome : (Hepaticse) orders Eicciacb^, sporangia 

 valveless, without elaters : Marchantiacece, sporangia dependent 

 valvate or bursting irregularly ; Spores mixed with elaters : Junger- 

 manniacece. Sporangia erect, valvate ; Spores mixed with elaters. 



§ 2, Peristome mostly present, Musci [^Bryacece^. Spores 

 numerous, producing a prothallus which beats a single set of Arche- 

 gonia which yield fructifying plants. Pilicales — Filices \_Polypodi- 

 acece], sporangia annulate or rarely exannulate and closely crowded : 

 Ophioglossace<js, sporangia exannulate bivalvate : Equisetacece, spo- 

 rangia dependent, unilocular, bursting laterally: Marsiliacecs, spo- 

 rangia multilocular : Lycopodiacece, sporangia axillary, unilocular." 

 This arrangement seems to us an improvement on any with which 

 we are acquainted. It is not free from difficulties, but it is upon the 

 whole natural, and compares very favorably with rival systems. We 

 cannot but feel surprised that Mr. Berkeley so little appreciates the 

 value of Lindley's mode of nomenclature, which we had expected to 

 see at once accepted by all writers on the subject. In the case of 

 the ferns, for example, he has applied generally, yet not uniformly, 

 the terminations in acece, which ought to mark leading orders to the 

 sub-families ; whilst, in naming the order, he has preferred the old 

 title Filices to one formed on the analogy of other natural orders. 

 Not less objectionable is the practice of speaking of monopetalous 

 orders of plants, a term which conveys a false idea, and which all the 

 most accurate writers are abandoning. We recommend the term 

 synpetalous as concise and intelligible, and greatly preferable to 

 gamopetalous, which was recommended by De Candolle ; but the 

 continued use of a term like monopetalous, which expresses a view 

 imiversally acknowledged to be false, seems to us a serious evil. 

 Taken as a whole, we can hardly speak too highly of Mr. Berkeley's 

 work. It more than fulfils all reasonable expectations, and vnll 

 prove such a help to the cryptogamic botanist that he will account 



