ECONOMIC ZOOLOGY ENTOMOLOGY. 749 



A summary of the evidence as to the existence of plague among human beings 

 in the affected parts of Suffolk show that " there were 4 cases of true pneu- 

 monic plague in Holbrook in 1910, 8 cases of practically certain pneumonic 

 plague in Shotley in 190G and 1907, and 7 cases of possible bubonic plague In 

 Trimley in 1909 and 1910." It is said that the rat flea of Suffolk is Ccrato 

 pfiyUus fascialus. The means by which the disease was introduced into this 

 district is unknown ; the various theories which have been advanced are pre* 

 sented at some length. 



Investig-ations of " Liverpool virus," a rat-destroying preparation, K. 

 Steffenhagen {Arb. K. Gsndhtsamt., 36 (1910), No. 2, pp. 19S-220). — The cul- 

 tural and biological studies here reported are accompanied by a bibliography of 

 32 titles. 



Publications of the Bureau of Entomolog'y ( U. S. Dept. Agr., Div. Puds. 

 Circ. 16, pp. 9). — ^A list of publications of the Bureau of Entomology that are 

 available for free distribution by the Division of Publications of this Depart- 

 ment. 



Entomology, A. W. Morrill (Arizona Sta. Rpt. 1910, pp. 390-392) .—The 

 author reports that insect i^ests are fast assuming in Arizona the important 

 status they have long maintained in California. The woolly aphis has estab- 

 lished itself in Graham and Yavapai county apple orchards, where it was intro- 

 duced several years ago. 



The large red harvester ant ( Pogonomyrmcx sp.) is one of the most destruc- 

 tive insect pests in the Territory, the areas made bare in alfalfa fields by this 

 insect in some sections amounting to 5 or 10 per cent of the total acreage, and 

 being estimated at 2 per cent throughout the Salt River Valley. The harvester 

 ants also occasionally defoliate young citrus ti'ees and gnaw the bark, causing 

 (he destruction of the trees attacked unless they are promptly suppressed. 



Experiments conducted have shown carbon bisulphid to be too expensive for 

 general use against these insects in alfalfa fields. Potassium cyanid dissolved 

 in water and used at the rate of 1 oz. to 1 gal. of water is the cheapest and 

 best method for immediately checking them, but this treatment can not be 

 relied upon to eradicate them completely. London purple, although slow acting, 

 is stated to be the cheapest and most satisfactory insecticide of the many 

 tested ; it should be applied at intervals in powder form at the rate of 1 table- 

 spoonful scattered around the opening to each nest. 



Examinations of oranges were made in December, 1909 to determine the 

 injury caused by the citrus thrips (Euthrips citri). Of 100 navels selected at 

 random from the field boxes from each of 10 representative groves it was found 

 that an average of 25 per cent was so scarred that it should properly be classed 

 as second grade. The injury ranged in different groves from .3 to 57 per cent. 



Tenth report of the state entomologist of Connecticut for the year 1910, 

 W. E. Britton (Connecticut State Sta. Rpt. 1909-10, pt. 9, irp. VI+657-712, pis. 

 8, figs. l.'f). — The entomological features of 1910 are briefly considered, includ- 

 ing reports of the inspection of nurseries, imported nursery stock, and apiaries, 

 and of the gipsy moth work. 



During the work 8,234 gipsy moth egg masses and 8,936 caterpillars at burlap 

 bands were destroyed at Wallingford, where the area actually infested with the 

 moth is estimated at 0.378 of a square mile. During the season a tachinid para- 

 site (Tachina rneUa), which has previously been recorded as parasitic on the 

 gipsy moth in Massachusetts was bred at Wallingford. At Stonington but 1 

 egg mass and 146 caterpillars were found and destroyed. A brief account is 

 given of the brown-tail moth and its occurrence in Connecticut as previously 

 noted (E. S. R., 24, p, 455), 



