19161 ECONOMIC ZOOLOGY — ENTOMOLOGY. 155 



place where the number of cases of pink disease had increased greatly during 

 the last year. Indigofera arrecta was found to be attacked by pink disease, 

 but mildly and only in a few instances, where the host plants were not in good 

 condition. C'litoria cajanifolia has also been recorded as a host for pink disease 

 at the Buitenzorg Botanic Gardens. The form assumed by the fungus on the 

 above plants was the pink incrustation commonly observed on rubber, on which 

 usually, as on all these plants, no trace of basidiospores was found. 



The red rot of conifers, F. H. Arbott (Vcrtnont Sta. Bui. 191 (1915), pp. 3-20, 

 pis. 4, figs. 2). — According to the author the so-called red rot of conifers is due 

 to the fungus Trametes pini, which is primarily a parasite assuming more or 

 less the character of a saprophyte when the tree falls. The fungus is said to 

 attack tamarack, pine, hemlock, spruce, and balsam, its ravages being greatest 

 in unthinned stands, especially in pure stands of white pine. 



The infection apparently occurs mainly through broken branches which ex- 

 pose the heartwood, root infection being considei*ed doubtful. The principal 

 means of spreading the disease is through the sporophores, which are formed 

 on all host species but vary in form on different hosts, occurring on both stand- 

 ing and fallen trees. The damage to the wood is brought about by the solu- 

 tion of its lignin content by the enzym of the fungus and this injury appears to 

 cease when the tree falls. The damaged wood may be used in the manufacture 

 of boxes, tubs, wooden pails, etc. For prevention of spread of the red rot, 

 proper thinning, removing the diseased trees, and destroying the fruiting bodies 

 are recommended. 



The two rust diseases of the spruce, A. W. Borthwick and M. Wilson 

 (Notes Roy. Bat. Gard. Edinb., 9 (1915), No. U, pp. 6.5-69, pi. i).— Discussing 

 the life history of Chrysomyxa rhododcndri causing spruce blister rust and 

 also rust of rhododendrons, the authors state that although the presence of the 

 spruce is apparently not essential to the continued existence of the fungus, the 

 SEcidial stage on the spruce can exist only where the rhododendron is present, as 

 the infection of the needles is brought about only by the sporidia. Removal of 

 the rhododendron will, therefore, completely check the disease. The effect of 

 this disease on rhododendron is not very serious. In case of the spruce, the 

 diseased needles fall in the summer of infection, and in severe cases, the trees 

 may be almost stripped of their foliage. 



C. abietis, the needle rust of spruce, is also discussed as to its biology and 

 distribution. Certain spruces in a wood may be badly attacked while others 

 remain free from the disease. This is ascribed to the fact that infection takes 

 place in a certain definite stage in the development of the young leaves, which, 

 in some cases, does not coincide with the exact developmental stage of the 

 sporidia necessary to infection. While a considerable degree of defoliation may 

 take place, the disease usually fails to maintain itself through a long series 

 of years on any one tree, so that cutting down the trees on account of this dis- 

 ease is not recommended. 



Honey fung-us, C. Fkombltng (Forstw. CentbL, n. ser., 37 (1915), No. 7, pp. 

 299-30Jf) .— This is a somewhat general summation of observations on Agaricus 

 melleus regarding its activity and effects as related to some conifers in con- 

 nection with such conditions as age, soil, growth, spacing, and .shading by other 

 trees. 



ECONOMIC ZOOLOGY— ENTOMOLOGY. 



Birds of Porto Rico, A. Wetmore (Porto Rico Bd. Agr. E.xpt. Sta. Bui. 15 

 (1916), pp. lJ/0. pJs. 10). — This is a reprint, text unchanged, of Bulletin 326 of 

 this Department, previously noted (E. S. R., 34, p. 849). 

 47580°— 16 5 



