403 



plants while damp with soot or powdered lime, or spraying the leaves 

 with strongly-smelling tobacco water or with X.L.All Uquid insecticide, 

 also gives good results. 



Talbert (T. J.). Control of Some of the Important Garden and Truck 

 Crop Insects. — Missouri Agric. Expt. Sta., Columbia, Circular 

 no. 15, April 1917, 24 pp., 19 figs. [Received 10th July 1917.] 



This paper reviews the chief vegetable pests of Missouri, and gives 

 formulae for contact sprays for sucking insects and poison-bait for 

 chewing and biting insects. Spray- outfits for liquid and dust sprays 

 are described, and a spraying calendar is included. The paper contains 

 no new information. 



Haseman (L.). The Periodical Cicada in Missouri. — Missoiiri Agric. 

 Expt. Sta , Columbia, Bulletin no. 137, November 1915, 33 pp., 

 19 figs. [Received 10th July 1917.] 



This report was prepared in response to numerous requests of farmers 

 and fruit-growers for information concerning the periodical cicada 

 [Tibicen septemdecim]. Much of the information contained in the 

 bulletin has already been abstracted [see this Review, Ser. A, ii, p. 433]. 

 Experiments to determine the effect of climate on the two distinct 

 races (the 13-year and the 17-year) gave indeterminate results, but 

 obviously climatic conditions are not sufficient to account for the fact 

 that in the same field it requires 17 years for the one race to develop 

 and only 13 for the other. In Missouri, there are four broods of each 

 race ; these are classified and their origin and distribution discussed. 

 The broods consist of two forms, the larger form being the more 

 abundant. The dwarfed form was formerly described as a distinct 

 species. Cicada cassinii, but is now considered as a variety of the 

 periodical cicada. The favourite hosts are oak, apple, hickory, ash 

 and walnut trees, and sometimes vines and herbaceous plants. The 

 injury is done to the twigs, those in which eggs are deposited being 

 weakened or killed. The eggs are laid in June in nests dug into the 

 wood, the female dying after depositing her supply of eggs. The 

 young larva, which hatches after six or seven weeks, very soon drops 

 to the ground and enters upon its subterranean life. Experiments 

 conducted throughout the entire 17-year life-cycle revealed the fact 

 that six stages are passed underground, the first four being larval and 

 the last two uymphal periods, each stage being characterised by 

 structural differences. The cell of the young larva is usually formed 

 along the side of a small root, which constitutes its principal food 

 supply, but so little food is required each season that practically no 

 injury is done to the tree by the larvae. The nymph in its last stage 

 digs its way to the surface of the ground and ascends the nearest tree, 

 the adult emerging about the end of May. 



Natural enemies include, besides insectivorous birds and mammals, 

 small wasps, flies and mites, which feed upon the eggs and destroy 

 them in great numbers. Sphecius speciosus, a large digger-wasp, kills 

 the adults and stores them away in burrows as food for its young. 

 Dragon-flies have also been known to attack the adults. Common 

 whitewash or Bordeaux mixture will effectually prevent the deposition 

 of eggs. 



(C390) b2 



