337 



Penfodon auslmlis, a black Lamellicorn beetle, has been recorded 

 as attacking seedling maize, in which case it was present in the soil 

 from a previous crop of infested grass. 



Another beetle, a species of Clivina, destroys recently planted maize 

 seeds, which should be protected by dipping them in a repellent 

 mixture such as thin tar, and then in Ume-dust with which a little 

 Paris green has been mixed. This method, which is also used against 

 M-ireworms, does not affect the germinating qualities of the seed. 



Stored maize may be attacked by Calandra oryzae (grain weevil) 

 and by Sitotroga cerealella (Angoumois moth). C. oryzae, the 

 commonest Australian species, is a tropical and sub-tropical insect. 

 C. (franaria, which flourishes in cooler regions, has been recorded 

 only t\^ace, in imported grain. Both these weevils are best controlled 

 by the fumes of crude commercial carbon bisulphide, at the rate of 

 5 lb. or more to everv 1,000 cu. ft., applied at a temperature above 

 70° F. 



Jack (R. W.). Notes on the Larvae, etc, of some Rhodesian Tene- 

 brionidae.— *S. African Jl. Nat. Hist., Pretoria, i, no. 1, May 1918, 

 pp. 84-98, 2 plates. 



Several species of Tenebrionid beetles are of considerable economic 

 importance in southern Rhodesia owing to the attacks on crops made 

 by both the adult beetles and the larvae. 



Adults of Zophods boiei, Sol., emerge mainly at the commencement 

 of the wet season, but do not lay eggs until March or April. The 

 larvae feed during the winter and pupate in October and November, 

 so that there is one generation in a year. Adults have been known 

 to attack maize seed in dry ground, and sometimes cause serious 

 injury to newly planted tobacco. Species of the genus Psammodes 

 studied include P. scrobicolUs, Fhs., P. similis, Pering., as well as 

 larvae of P. pierreti, Fhs., and P. bqtesi, Haag. The larvae of Psam- 

 modes are active and are very camiibalistic in confinement. They 

 feed largely on the under-ground portions of plants and constitute 

 a serious pest of tobacco, kiUing the plants by eating into the under- 

 ground stems. They show a particular liking for potato tubers. 

 Adults of P. scrobicolUs emerge at the commencement of the rains 

 and oviposit at once. The life-cycle lasts three years, most of which 

 is passed in the larval stage. The life-history of P. similis has not 

 been worked out ; growth in both these species seems to take place 

 mainly during the wet season. These species occur chiefly on sandy 

 soil, either sandstone or granite ; the larvae have not been recorded 

 as injurious in diorite areas. The larvae of Distretus amplipennis, 

 Fhs., have similar feeding habits to those of Psammodes. The beetles 

 emerge and oviposit at the beginning of the rainy season. This 

 genus is commonest on the sand veld, but occurs also on the diorite. 

 TracJiynotus geniculatus, Haag. , in the larval stage has similar feeding 

 habits ; two species of this genus are serious pests of tobacco. Adults 

 of T. genicidatus emerge in April, at the end of the rains, and the life- 

 cycle occupies one year, though occasional specimens may occupy 

 two years in development. Anomalipus plebeius, Pering., attacks 

 potato tubers ; the life-history is not known, but adults emerge and 

 oviposit at the beginning of the rainy season. 



(C485) B 



