245 



ready solubility in water. A high degree of humidity, such as 98 to 

 100, does not cause injury unless accompanied by a temperature 

 exceeding 70° F. 



Cotton (R. T.). Scale Insects and their Control. — Bd. Commiss. Agric., 

 Rio Piedras Expt. Sta., San Juan, P.R., Circular no. 9, 1917, 

 7 pp. [Received 12th April 1917.] 



This popular article on the scale-insects of Porto Rico contains 

 little new information. The most successful spray used on the island 

 for these pests is kerosene emulsion, 1 part to 15 parts water. For 

 citrus scales an emulsion is recommended composed of 8 lb. or 1 U.S. 

 gal. whale-oil soap, 2 U.S. gals, corvus or red junior oil, 1 U.S. gal. 

 water. Two or three weeks after application, the dead scales should 

 be scrubbed off the trunks. For pineapple mealy-bug [Pseudococcus 

 bromeliae] the following emulsion is recommended : 2 U.S. gals, 

 kerosene oil, h lb. blue cloud soap or caustic potash soap, 1 U.S. gal. 

 water. One part of this emulsion should be used to 18 parts water. 

 This should not be used on the newly formed fruit buds and must be 

 applied with a fine spray powerful enough to remove the mealy coat 

 of the insects and saturate them with the spray. 



Faulwetter (R. C). Dissemination of the Angular Leafspot of Cotton. 

 — Jl. Agric. Research, Washington, D.C., viii, no. 12, 19th March 

 1917, pp. 457-475, 2 figs. 



In connection with the dissemination of angular leaf spot of cotton, 

 caused by Bacterium malmcearuni, investigations have been made to 

 determine the role played by insects in the spread of this disease. 

 As Jassids were the most common and most active insects on the 

 cotton plants under investigation, these insects were chosen for the 

 experiments, and tables are given showing the results of treating 

 plants infested by them with cultures of B. malvacearum. While 

 the data are not conclusive, the results of the tests lead to the con- 

 clusion that insects have a very slight, if any, effect in dissemination 

 of the disease, and this is borne out bv later observations in the open 

 field. 



A bibUography of 40 references is appended. 



Morrison (H.). Monograph of the Nearctic Hymenoptera of the 

 Genus Bracon Fabricius. — Separate, dated 7th March 1917, from 

 Proc. U. S. Nat. Mus., Washington, lii, pp. 305-343, 4 plates. 



A key is given to the species of this genus, which are described. 

 Bracon vulgaris, Cress., is the only species for which there are breeding 

 and host records, this species having being recorded as a parasite of 

 the sugar-beet web-worm, Phhjctaenodes (Loxostege) sticticalis, L. 



Ehrhorn (E. M.). Division of Plant Inspeetion.^ — Hawaiian Forester 



and Agriculturist, Honolulu, xiv, no. 1, January 1917, pp. 8-10. 



[Received 12th April 1917.] 



During the month of December 1916, a pine tree infested with a 



species of Chermes was fumigated before dehvery. A nest of ants, 



Prenohpis longicornis, was found in packing material in a box from 



Japan ; the box was fumigated with carbon bisidphide for 48 hours, 



