452 EXPERIMENT STATION EECOED. 



The bulletin includes an account of the food plants, life history, and habits, 

 with technical descriptions of the several stages of these katydids. 



A small chalcidid belonging to the genus Anastatus is the only enemy of 

 the egg discovered during the iuA-estigation. This parasite is much more effec- 

 tive in checking the angular-winged katydid than ;S. furcata in orange groves 

 in the San Joaquin Valley. 



The angular-winged katydid, while much less important, is also responsible 

 for a certain amount of injury to orange trees. The first instar nymphs of 

 M. rJiombifolium feed principally, if not wholly, upon the leaf surface, removing 

 merely a chlorophyll layer. Later stages gnaw clear through the leaves, fill- 

 ing them with ragged holes and destroy a larger amount of foliage in propor- 

 tion to their number than does the fork-tailed, katydid. It has never been 

 observed to attack blossoms or fruit. The eggs of this si)ecies are also attacked 

 by Anastatus sp., it being estimated that SO per cent or more of all eggs depos- 

 ited are destroyed. 



Spraying experiments conducted and here reported have led to the recom- 

 mendation of two applications of arsenite of zinc at the rate of 2 lbs. per 100 

 gal. of water, or two applications of arsenate of lead at the rate of 4 lbs. 

 per 100 gal. of water. The first application should be made, at the latest, 

 immediately after most of the petals have fallen; the second application, from 

 10 days to two weeks after the first. " If it seems desirable to spray for 

 the citrus thrips also, lime-sulphur should be added to the above at the rate 

 of 2 gal. per hundred, and a third application of lime-sulphur only, at the 

 same dilution, should be made about two or three weeks after the second. The 

 cost of spraying will vary somewhat according to size of trees, cost of labor, 

 team hire, insecticides, etc., but with ordinarily good management will not 

 exceed $5 per acre." 



Control of the chang'a, S. S. Grossman and G. N. Wolcott {Porto Rico Bd. 

 Agr. Exi)t. 8ta. Circ. 6 (1915), pp. 5). — Experiments extending over a period of 

 several years are said to have led to a very easy, cheap, and effective method 

 of destroying this mole cricket (Scapteriscus didactylus) , accounts of which 

 by Barrett (E. S. R., 14, p. 885) and by Worsham and Reed (E. S. R., 29, 

 p. 557) have been previously noted. This consists in the use of Paris green 

 2.5 to 3 lbs. to 100 lbs. of low grade flour. This mixture, when placed around 

 the tobacco plant in a shallow trench about 1 in. deep and 3 in. from the 

 tobacco plant at the rate of a heaping teaspoonful to the plant, results in prac- 

 tically 100 per cent stand. Broadcasting before planting at the rate of from 

 250 to 300 lbs. per acre was also effective. The cost, including labor, is said 

 to amount to $8 to $10 per acre. This method can also be successfully employed 

 in protecting other crops. 



Aphids or plant lice attacking sugar cane in Porto Rico, T. H. Jonks 

 (Porto Rico Bd. Agr. Expt. Sta. Bui. 11 (1915), pp. 19, pis. 2).— This bulletin 

 presents brief accounts of two species of plant lice that attack sugar cane in 

 Porto Rico, namely, SipJia flava, to which the name " yellow sugar cane aphis " 

 is applied ; and Aphis setarice, to which the name " brown sugar cane aphis " 

 is given. 8. flava occurs on the under surface of the cane leaves, especially 

 those which have begun to bend over, while A. setarice occurs at the junction of 

 the leaf sheaths and leaf blades of young cane on the lower surface and on 

 either side of the midrib. 



Observations and experiments on the San Jose scale, S. A. Forbes (Illinois 

 Sta. Bui. 180 (1915), pp. 5It5-561, figs. 3).— A brief note is given on the life 

 history of the San Jose scale, including a diagram of annual generations de- 

 scending from one hibernating female, followed by a report of tests of orchard 

 sprays. The work is summarized as follows: 



