6 9 8 SCIENCE PROGRESS 



requirements of this class of reader the descriptions of the different species lay 

 particular emphasis on characters of foliage and fruit. The so-called seeds of 

 most of the common grasses are figured, and artificial keys are supplied based 

 respectively on the foliage, the floral characters, and the "seed." The first named 

 of these loses much of its usefulness through the omission of such species as 

 Koeleria cristata and 7 udia decumbens, both of which are so common as to 

 render their exclusion indefensible. 



In the Botanical section the student would have been greatly assisted if 

 important diagnostic features had been brought into prominence by the use of 

 distinctive type. In some instances useful characters have been omitted, as for 

 example in the description of Holcus mollis, where we find no mention of the 

 exserted awn, a feature which, in the fruiting condition, offers the most facile field 

 distinction from its congener. We deplore, too, the rather cursory treament of 

 critical forms such as the species and varieties of Festuca and Agrostis. 



The short section on the distribution of grasses might well have been fuller 

 and, on some points, better informed. For instance, on p. 23 we find the 

 statement that Psamma and Elymus are Halophytes, whilst no mention is here 

 made of the really halophytic grasses such as Glyceria maritima, Agrostis 

 maritima and Lepturus incurvatus . Surely, too, among the species characteristic 

 of calcareous soils Poa rigida and Poa compressa might have been included 

 rather than such atypical species as Nardus stricta and Triodia decumbens, which 

 occur almost exclusively on siliceous soils or, if in calcareous areas, where the 

 surface layers have become leached. 



In Part II. the agricultural value and characteristics of farm grasses are dealt 

 with, and here a considerable amount of data is given relative to commercial 

 "seed" and its common impurities. 



Taken as a whole the book furnishes much of the information that is required 

 by an agricultural student and, in so far as stress is laid on points of economic 

 importance, marks a distinct advance on the current works on agrostology. 



E. J. Salisbury. 



The Grasses of Ohio. By John H. Schaffner. [Pp. 79, with two plates.] 

 (Ohio State University, 1917. Price $0.50.) 



Mr. Schaffner has provided what may be described as a Graminaceous Flora 

 of the State of Ohio. Two synopses and a key to the tribes and genera precede 

 descriptions of all the grasses native to this district together with those which 

 have been introduced or are commonly cultivated, a total of about 180 species. 

 Artificial keys are provided for all the larger genera, but unfortunately there is no 

 attempt to distinguish the segregates of polymorphic types, such as Festuca ovina 

 and Koeleria cristata, and in many cases the diagnoses might well have been 

 amplified. Economically the recognition of the variety or microspecies is often 

 more important than the separation of the larger aggregates, since the former in 

 general have a more restricted distribution in relation to the habitat conditions. 



Floral characters are chiefly relied upon, and only occasionally is data fur- 

 nished with respect to ligular morphology, etc., though vegetative distinctions are, 

 here and there, embodied in the specific keys. The appeal of the text is thus 

 rather to the systematist than to those interested in the group from the agricultural 

 or economic standpoint. 



E. J. Salisbury. 



