316 



growing in galleries bored in the wood by the parent beetles. Certain 

 species of ambrosia fungi are beUeved to be definitely associated with 

 certain species of beetles. The spores of the fungus are distributed 

 by the adults either accidentally or intentionally, as in the case of the 

 European species Xyleborus disjxir, ¥., where the spores are carried 

 in the crop and later regurgitated, or as in some Indian forms, where 

 the dorsal pores of the thorax serve as carriers. The trees attacked 

 are those which have been weakened by other insects, fungi, etc., or 

 have been recently felled. Healthy trees, and barked or partially 

 seasoned unbarked logs are rarely attacked, while dry timber is 

 immune. Direct fatal injury has been recorded in the case of living 

 tea, coffee, camphor, pomaceous and citrus fruits, etc. 



The galleries in the sapwood and outer heartwood are referable to 

 three types. In the case of X. major, Steb., X. semigmnosus, Bldfd., 

 X, fornicatus, Eichh., and EccopLoptenis sex-spinosus, Motsch., the 

 gallery consists of an entrance tunnel bored horizontally into the sap- 

 wood of the sal tree [Shorea robiista] ending in an irregular chamber from 

 which a number of branches are given off. Pairing in X. major occurs 

 before the migratory flight ; eggs are laid in groups of from three to six 

 in the innermost branches. Egg-laying and extension of the galleries 

 continues as long as conditions are favourable. Pupation of the larvae 

 takes place in the lateral branches or in the central chamber. A very 

 large proportion of the adults are females. In X. fallax, Eichh., the 

 entrance tunnel runs horizontally and radially into the sapwood, and 

 from it the main tunnel passes right or left, following the rings of 

 wood. Secondary branches given off from the main tunnel are occupied 

 by eggs or larvae. Pupation usually takes place in special chambers 

 on the main and lateral galleries or in the outer part of the sapwood. 

 Modifications of this type are found in X. perforans, Woll., X. andrewesi, 

 Bldfd., X. parvulus, Eichh., X. suhmarginatus, Bldfd. and X. laticollis, 

 Bldfd. The galleries of the Scolytinae differ in the presence of a 

 special pupal chamber for each individual, formed on the primary'' or 

 secondary tunnels. In the genus Crossotarsus the entrance gallery 

 runs radially and horizontally to a depth of from 2 to 4 inches, then 

 gives off a series of vertical branches, terminating in vertically arranged 

 pupal chambers. Eggs, larvae and immature adults occur in all parts 

 of the system. 



The following is a list of ambrosia beetles attacking Shorea rohusta :— 

 Scolytinae : X. andreivesi, Bldfd. ; X. aplanatus, Wich. ; X. fallax, 

 Eichh. ; X. laticollis, Bldfd. ; X. major, Steb. ; X. parvulus, Eichh. ; 

 X. perforans, Woll. ; X. schlichii, Steb. ; X. semigranosus, Bldfd. ; 

 X. suhmarginatus, Bldfd. Platypodinae : Crossotarsus bonvouloiri, 

 Chap. ; C. saundersi. Chap. ; Diapiis furtivus. Samps. ; D. (piinque- 

 spinatus, Chap. ; Platypus cavus, Stroh. ; P. cupulatus, Chap. ; 

 P. curtus, Chap. ; P. solidus, Chap. ; P. pilifrons, Chap. 



Morrill (A. W.). Report of the Entomologist of the Arizona 

 Commission of Agriculture and Horticulture. — Arizona Commiss. 

 Agric. and Hortic, 7lh Ann. Rept. for the Year ending 30th June 

 1915, Phoenix, 24th December 1915, pp. 9-50, 18 figs., 6 plates. 

 [Received 23rd May 1916.] 



During the year ended 30th June 1915, the following insect pests 

 were found on imported nursery stock or other plants : — Coccus 



