316 Review of Gi^ay^s Botany. 



These, heretofore, to the student in botany, have been sealed 

 and secret forms, which have set at defiance his efforts to 

 discover ; and, while he has admired their elegance, beauty, 

 or minute wonders, he has been obliged to be content to 

 know their history in the most meagre and unsatisfactory 

 way. Scattered, too, as were their original descriptions, 

 through rare, costly, and foreign works, (the production of 

 European botanists, to whom they were at first sent by 

 Muhlenberg and earlier collectors of North American plants,) 

 scarcely any one seemed capable of telling what were the 

 most ordinary forms which our localities furnished. Very 

 brief descriptions of a few, were to be met with in the later 

 editions of Eaton's Manual^ affording a meagre assistance to 

 those, who, in this department, may be said to have "pur- 

 sued knowledge under difficulty." With the present facili- 

 ties, we are happy to add, in the words of Prof. Gray, in his 

 Preface, (p. x,) "it may be hoped that these beautiful but 

 neglected tribes will become as familiar to botanists as our 

 more conspicuous flowering plants now are." 



The specification of another obscure, but deeply interesting 

 order, the Lichenes, was intended to have been embodied in 

 this work. The value of the accurate study of these lower 

 forms of vegetation cannot, at this time, be exhibited ; suffi- 

 cient, however, may it be to say, that, for subjects of curious 

 research and singular advantage, scarcely any tribe exceeds 

 them. 



EspeeiaUy do I regret, says Dr. Gray, that the unexpected bulk of 

 the volume has compelled the omission of the family of the Lichenes, after 

 they had very carefully been prepared expressly for this work, in compli- 

 ance with my invitation, by the well-known lichenologist of this country, 

 Mr. TrcKERMAN. Nothing but the apparent impossibility of including the 

 whole within the covers of a single duodecimo volume, and the assured 

 expectation that it will immediately be given to botanists in another form, 

 has reconciled me to the exclusion of this important contribution. (Pre- 

 face, vi.) 



This contribution, it is our pleasure to add, has since ap- 

 peared in the Proceedings of the American Academy of Arts 

 and Sciences, and also in the form of a " Synopsis." 



A rich branch of botany is to be found in the vast number 

 of Algge, which, as seaweeds, or as the tenants of our fresh- 



