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DupoRT (L.) & Hautefeuille (L.). Gum Lac and the Breeding of 

 Tadiardia. — Internat. Rev. Science and Practice Agric, Mthhj. 

 Bull. Agric. Intell. and PI. Dis., Rome, vii, no. 8, August, 1916, 

 pp. 1153-1155. [Abstract from (1) Duport (L.). L'Insecte a 

 Stick-lac ; (2) Hautefeuille (L.). La gomme laque et son 

 traitement industriel, in Bulletin economique de VIndochine, 

 Hanoi-Haiphong, nos. 112-116, pp. 182-189 and 872-994, March- 

 April and November-December 1915.] [Received 13tli December 

 1916.] 



This study contains a summary of our knowledge of the lac insect, 

 Tachardia lacca, Kerr, the life-history of the insect itself being dealt 

 -with by the first-named author and the production and preparation of 

 lac by the second. 



T. lacca is found principally on Butea frondosa, Cajanus indicus, 

 Picas religiosa, Zizyphusjajxba, and especially Schleichera trijiiga,v^'hich. 

 supplies the best gum lac. It is stated that the most suitable spots for 

 production should have a moderately hot climate where the ramfall 

 amounts to about 29 "25 inches per annum. Observations made in 

 Indo- China give from 1,310 to 2,130 feet as the hmits of altitude. 

 The production of lac is also said to require the presence of a species of 

 large red ant, which, according to the natives, drives away all other 

 ants injurious to the scale. A scheme of research is proposed to com- 

 plete a survey of the areas likely to be productive, to specify more 

 clearly the nature and distribution of the most useful species or varieties, 

 to study the different kinds of lac produced and the reasons why some 

 kinds are insoluble in alcohol, and to extend the cultivation of 

 Schleichera trijuga, which is also useful owing to its edible kernel being 

 rich in oil. Further entomological study of T. lacca is also required, 

 especially regarding the economic conditions of its rearing, the trade 

 and exchange of the eggs and the ant associated with it. 



Some particulars are also given respecting the plant and apphances 

 required for the refining of gum lac, 



Stewart (V. B.) & Leonard (M. D.). The Part played by Insects in 

 the Spread of Bacillus amylovorus. — Internat. Rev. Science and 

 Practice Agric, Mthly. Bull. Agric. Intell. and PI. Dis., Rome, 

 vii, no. 8, August 1916, pp. 1198-1199. [Abstract from Phyto- 

 pathology, Baltimore, Md., vi, no. 2, pp. 152-158.] [Received 

 13th December 1916.] 



This is an account of experiments carried out with a view to ascer- 

 taining whether sucking insects are capable of spreading and inoculating 

 healthy plants with Bacillus amylovorus. Young pear and apple trees 

 were enclosed in wire cages and cultures of B. amylovorus in agar 

 were spread in abundance on some of them. The following insects were 

 introduced into each cage : — Pollenia rudis, F., Empoasca mali, 

 Le B., Psylla pyricola, Forst., Plagiognathus politus, Uhler, and Sapro- 

 myza bispina, Lw. Though the insects were at liberty to go from one 

 plant to another, the disease was unable to spread from the infected 

 to the healthy ones. This is probably due to the fact that some sucking 

 insects are not able to produce lesions of the tissues such as would 

 facilitate the entry of this organism. The false tarnished plant-bug, 



