7 6 THE NA TURE-S TUD Y RE VIE IV [ 2 : 2 — febru a ry, igc 6 



berries, raspberries, roses and others. It seems to me the reason why these 

 plants produce thorns and prickles is because "it is their nature to." 



Naming Forest Trees in Streets and Parks. The increased interest 

 in forests and forest trees has, among other things, led many city and town 

 officials to seek to make known the names of trees growing in streets and 

 parks. Not only are such trees in very many cases now without marks of 

 identification, but in not a few cases they have been labeled with incorrect 

 names. The Forest Service of the U. S. Dept. of Agriculture has devised 

 plans by which its co-operation may be secured in correctly identifying the 

 public trees of any community which may. care to call upon it. 



Cattle Ticks. The Bureau of Animal Industry, United States Depart- 

 ment of Agriculture, will soon issue a publication on the cactle disease 

 known as Texas fever, which was shown several years ago to be due to a 

 parasite transmitted by the cattle ticks. According to the estimates, the 

 ticks are thus directly responsible for an annual loss to stockmen in the 

 United States of over $40,000,000. The new publication will propose 

 methods for controlling the ticks. Popular descriptions and colored plates 

 will be contained in the new bulletin. 



Trees for Fence Posts. It is estimated that in this country more than 

 one billion wooden fence posts are set each year. A very large number of 

 these are cut from trees yielding less than five posts each. This great 

 demand and rapidly disappearing forests have given a new impetus to forest 

 planting in the Middle West. Hardy catalpa,' black locust, osage orange, 

 Russian mulberry and red cedar are being planted. The first three produce 

 five inch posts in ten to fifteen years. 



Insects as Carriers of Disease. This interesting subject was reviewed 

 by A. E. Shipley, F. R. S., in a paper addressed to the scientists at the 

 British Association, at Pretoria, last summer. The main points of the 

 address are as follows : 



The last fev years are marked in the annals of medicine by a great in- 

 crease in our knowledge of certain parasitic diseases, and above all, in our 

 knowledge of the agency by which the parasites causing the diseases are 



conveyed. 



Chiw among these agencies in carrying the disease-causing organisms from 

 infected to uninfected animals are the insects ; and, amongst the insects, 

 above all the flies. Flies, e. g., the common house-fly, can carry about with 

 them the bacillus of anthrax. Flies, ants, and other even more objectiona- 

 ble insects, are not only capable of disseminating the plague-bacillus from 

 man to man, and possibly from rat to man, but they themselves fall victims 



