5^ BOTANICAL GAZETTE [january 



posed of Chlamydomonas, Pleurococcus, various blue-green algae, IVIyxophyceae, 

 and diatoms. The animals of the ''vader" and these algae are of enormous 

 importance in reclaiming land from the sea. A chapter is devoted to the enalids, 

 that is, the plants of submerged meadows, among which Zostera, Ruppia, and 

 similar plants dominate. 



An entire chapter is devoted to the ecology of Salicornia Jierhacea (another 

 evidence of the thorough treatment of the book), which is the pioneer emergent 

 plant of the salt marsh; its upper line is determined by the tide, since over three 

 hours of complete emergence seems detrimental. Beyond the Salicornia zone 

 are various halophnic plants, largely grasses, whose distribution varies largely 

 with soil changes. Sand-binding grasses like Glyceria maritima dominate in the 

 sandy m^arshes of this t>-pe. In the chapter which compares the salt marshes 

 of the North and East seas, it is noted that the North Sea flora is much more 

 halophytic than is that of the less salt>' East Sea. It is very curious, however, 

 that some true halophytes of the East Sea region are not known from the North 

 Q^ -D^.j —amps " "^' 



(up to 3 per cent. salt). Of much interest are the bacterial swamps in which the 

 purple sulfur bacteria and Beggiatoa dominate; these occur of course where 

 there is decajing vegetation. A chapter is devoted to the unevennesses of salt 

 maishes (such as mounds formed by ants, moles, etc.), and their vegetation, 

 which differs much from the ordinary- flora of the mai^h. The influence of arti- 

 ficial land reclamation is the subject of another chapter; dike-building soon 

 results m the disappearance of salt from the marshes, and the development of 

 the^ vegetation into an artificial meadow. The final chapters deal with the eco- 

 togical characteristics of haloph>tes. Most species are hapaxanthic turf-buHdeis. 

 Woody plants are missing except for two half-shrubs. Succulence and leaf 

 isoIateraHty are common. Th^ flowers are largely wmd-poIUnated, and the seeds 

 are scattered more by water currents than by other means. The thoroughness 

 of this work makes us long for the other members of the series.— H. C. Cowles. 



A new textbook of biology 



That the teaching of bioiogj- in secondary schools has not yet reached an 

 accepted method is evident with the appearance of each new textbook. Formerly 

 courses m general biology were recommended, without any separation into botany 

 and zoology. Later it became more common to offer unit courses in zoology, or 

 botany, or physiology. During aU this time, however, there have been adherents 

 to the elementary course in general biology, and some excellent arguments for such 

 a course have been recognized by ahnost every teacher. 



In a recent book by Hl-nter^ we have another attempt to solve this problem. 

 it IS mtended to present botany, zoobg)-, and human phvsiology in one course 

 to students m the first year of the high school, and has been used in the New 



=^ Hunter, George William, Elements of biolc^. NewY*^k: Amen- 



can 



