44 The Plant World. 



under any conditions, and as it gathers its most destructive 

 force in ascending a slope, the burnt areas will be limited. Out 

 of one hundred pine trees (Pinus arizonica) examined in order 

 as they stood along a certain high ridge in the Rincon mountains 

 of Arizona, in October, 1909, nine or ten were found to have 

 been struck by lightning at one time or another, and a number 

 were severely burned. In other more exposed places the dam- 

 age was much greater, and a certain high point in the Santa 

 Ritas showed perhaps as high as thirty to fifty per cent of the 

 trees as having been struck by lightning, while many were also 

 severely scarred by fire. During the rainy season of summer 

 these mountain peaks literally become the lightning conductors 

 of the desert, and the forest growth is often seen to suffer heavily 

 from mechanical disruption by frequent bolts as well as by re- 

 sultant local fires. 

 Tucson, Arizona. 



BOOKS AND CURRENT LITERATURE. 



Peat Deposits of Maine, by Edson S. Bastin and Charles A. 

 Davis, has been issued as Bulletin 376 of the United States Geo- 

 logical Survey, bearing date of 1809. It is accompanied by a map 

 of Maine, showing localities where peat has been found in im- 

 portant amounts. Between forty and fifty such localities are 

 marked, nearly all of them in the southern half of the state. The 

 northern part doubtless may be expected to make a far better 

 showing when it is more fully explored. The conditions of peat 

 formation, the plants concerned in its growth, the variable 

 character of peat deposits, and the present floras of peat bogs 

 are among the subjects of botanical interest. On the economic 

 side there are discussions of location, market, methods of pros- 

 pecting and estimating, the choice of machinery and the utiliza- 

 tion of the product. About one-half of the paper is devoted to 

 detailed descriptions of localities, with maps giving the location 

 and areas of the bogs examined, and the locations of test borings, 

 thus presenting a body of exact intormation indispensable to 

 those who may engage in further investigation or in the ex- 

 ploitation of the resources described. 



