39 



Virginia is somewhat misleading in that it includes at least half 

 a dozen species which in the southern states are known only in 

 the mountains, and not in the coastal plain, and one or two whose 

 occurrence northeast of Maryland is doubtful. (It is interesting 

 to note that nearly half of the 44 spermatophytes listed as pine- 

 barren plants are monocotyledons, and the proportion would be 

 still larger if the corrections just indicated had been made.) 

 This part closes with an instructive discussion of the factors 

 by which vegetation provinces are differentiated, and a bibliog- 

 raphy of works relating to the flora of Maryland and the District 

 of Columbia. 



In Part 3, the longest and most important of all, the vegetation 

 of each of the five subdivisions of the state is classified by habitat; 

 Dr. Shreve taking the easternmost, middle and westernmost, 

 Dr. Chrysler the "Western Shore" (that part of the coastal 

 plain west of the Bay), and Dr. Blodgett the upper midland zone. 



In the habitat lists prepared by Dr. Shreve, the species, in- 

 stead of being arranged in taxonomic, alphabetical, or merely 

 haphazard order, as was customary up to four or five years ago 

 (and is yet, to a considerable extent), are divided into trees, 

 shrubs, and herbs (bryophytes and thallophytes being left out 

 of consideration), and arranged in approximate order of abun- 

 dance (as stated in a rather inconspicuous way in a footnote on 

 page no). Unfortunately in such lists the trees are mentioned 

 only by their common names, and these are run into paragraphs 

 instead of being arranged in columns like those of the herbs, 

 which makes this part less valuable for purposes of reference 

 than it should be. In order to find from the index all that is 

 said in the book about any particular species of tree its common 

 name has to be constantly borne in mind. The names of the 

 herbs are sometimes run into paragraphs too, but in most cases 

 they are arranged in single columns, thus wasting considerable 

 space which might easily have been filled with condensed informa- 

 tion about the structure and adaptations, or even the geographical 

 distribution, of each species. If smaller and more closely set 

 type or double columns had been used for the herbs each habitat 

 list would have been confined to one or two pages, and thus 



