325 



Notes (by W. Nowell and F. W. Urich) on the pests and diseases 

 enumerated are appended ; the parasol ants referred to are Atia 

 cephalotes and A . odospinosa, the cacao beetle, Stirastoma depressimi ; 

 while the locusts include several species, of which the most injurious 

 is Schistocerca paranensis (South American migratory locust). 



As a precaution against the introduction of the pink bollworm 

 [Platyedra gossypiella], the importation into the Colony of cotton seed, 

 seed cotton and ginned cotton is prohibited, except under a permit 

 issued by the Director of Agriculture. 



Hall (G. C). A Carbon-tetrachloride Killing Bottle.— £«/. News, 



Philadelphia, Pa., xxxiii, no. 4, April 1922, pp. 112-113. 



Carbon-tetrachloride is a very useful kilUng agent for insects, the 

 method adopted being to place a piece of felt at least a quarter of an 

 inch thick at the bottom of the bottle and cover this with cotton- 

 wool to a depth of about one inch. The carbon-tetrachloride should 

 be poured down the side of the bottle to avoid wetting the cotton, 

 in sufficient quantity to saturate the felt. The bottle thus prepared 

 will last a day in active service, and when corked will keep for months. 



Parrott (P. J.). Control of Sucking Insects by Dusting.— Pwc. 



67th [4th] Ann. Meeting N. Y. State Hortic. Soc, Rochester. 

 N. Y., 1922, pp. 35-49. 4 tables. 



All pubhshed results on the control of the San Jose scale [Aspidiotus 

 perniciosus] by dusting are inconclusive. This insect is more resistant 

 than any other species to insecticides in powder form. Dusting prepara- 

 tions composed of sodium, calcium and barium sulphides were less 

 effective than the standard lime-sulphur spray solution ; they also 

 caused severe scorching of unfolding leaves. The deficiency of dusting 

 materials is probably due to the poor insecticidal properties of the 

 various powdered sulphides. 



In experiments undertaken against pear psylla (Psylla pyricola) 

 the adults showed a marked susceptibiHty to nicotine in dust and liquid 

 forms. Dilutions of nicotine, considerably greater than the minimum 

 necessary to control most sucking insects, were as toxic as the standard 

 concentrations. The practicability of freeing an entire orchard remains 

 to be demonstrated. The insects show a greater resistance to nicotine 

 during periods of low temperatures. 



The effect of nicotine in dust and liquid form on apple red bugs 

 [Lygidea mendax], Myzns ribis (currant aphis) and Brevicorvne [Aphis) 

 brassicae (cabbage aphis), together with the conclusions drawn from 

 the dusting experiments here described, have already been noticed 

 [R.A.E., A, X, 305^ 



Hartzell (F. Z.). Pear Psylla Problems.— Proc. 67th [4th] Ann. 

 Meeting N. Y. State Hortic. Soc, Rochester, N. Y.," 1922, pp. 

 50-55. 



Tabulated results are given of spraying experiments made in July 

 1921, which, so far as the author knows, are the first proof that psylla 

 adults [Psylla pyricola] are susceptible to nicotine dusts. Further 

 investigations showed that the application had destroyed the older 

 n^TTiphs and adults, but had not killed the younger n\Tnphs enveloped 

 in honey-dew. Other tests proved that lime-nicotine and sulphur- 



