FORESTRY. 135 



Eztensiou work in horticulture, L. H. Bailey (Kew York Cornell Sta. Bui. 110, 

 pp. 125-1G4). — This bulletin consists of a report on the progress of the work under- 

 taken by the Cornell University Agricultural Experiment Station in pursuance of 

 the requirements of the experiment station extension law of the State. The 

 researches and experiments in horticultural and entomological lines are briefly out- 

 lined, and the objects, methods, and results of extension of university teaching to 

 the people of the State are given. Conspectuses of 5 so-called schools of horticul- 

 ture held in diU'ereut parts of the State are given, and in addition are included 

 synopses of the lectures delivered at these schools, dealing with different phases of 

 horticulture, botany, chemistry of the soil, insect and fungus diseases, etc. A list 

 of the bulletins published under the ausruces of the experiment station extension 

 bill is appended. 



FOEESTRY. 



The internal temperature of trees, C. Flammarton {Bui. Min. 

 Agr. France, 15 {1896), No. 2, pp. 277-279, fig. 1).—T\iq author has made 

 a study of the internal temperature of a number of trees and finds that 

 it varies with the temperature of the air and is transmitted to the 

 interior in proportion to the diameter of the tree and the condition of 

 the wood whether living or dead. The minimum temperatures observed 

 February 7 at 9 p. m. were for air — 15.1°, dead poplar — 14.9°, fir 

 — 11.8°, cherry — 14.0°, dead cherry — 14.2°, black locust undergrowth 

 — 12.3°, and black locust — 10.2°. Figures are given for the internal 

 temperatures of the same trees August 21, and it is shown that in the 

 dead wood there was a wider diurnal range than in the living. 



The effect of the diameter of the tree upon its temperature is shown 

 by observations made during 8 days upon a large and a small black 

 locust tree. The average temperature for 12 days was air 7.3°, small 

 tree 9.4°, and large tree 10.1°. The average internal temperature of 

 resin-bearing trees is said to be higher than those not producing it. 



Mechanical and physical properties of Southern pine, B. E. 

 Fernow ( TJ. 8. 1)ept. Agr., Division of Forestry Circular 12, pp. 12, dgms. 

 4). — Notes are given on the mechanical and physical i^roperties of the 

 long-leaf pine {Pinus palustris), Cuban pine (P. heterophylla), short- 

 leaved pine (P. echinnta), and the loblolly or old field pine (P. twda). 

 The data given in the present circular are condensed from a special 

 bulletin ui)on the same subject that is to be issued in the near future. 



Familiar trees and their leaves, F. S. Mathews {New York: D. Appleton <|- Co., 

 1896, pp. X, 320, figs. 215). — This handsome work is an artist's description in popular 

 language, illustrated in a rather satisfactory manner, of about 200 of the more com- 

 mon trees and larger shrubs of the region covered by Gray's and Chapman's manuals, 

 with occasional references to some growing beyond these limits. The plan of the work 

 is to attbrd a ready means for identifying trees by means of their foliage, other char- 

 acters being called upon when necessary. The author seems to have been very suc- 

 cessful in his undertaking, and the work will be found useful and instructive to the 

 botanist as well as to those who are unfamiliar with botanical details. The nomen- 

 clature is that of Gray, with the names as given by Sargent as synonyms. A copious 

 index is given of the scientific, common, and ordinal names of every species and 

 variety described in the text. 

 5096— No. 2 4 



