( 6ii ) 



CHAPTER XXII, 



RHYNCHOPHORA {contiiiiud)^Fami\y PLATYPODIDAE. 



The beetles of this family are easily distinguishable from the Scolytidae 

 (Ipidae) owing to their more elongated form with parallel sides, the large 

 exserted head, and the long legs with slender five-jointed tarsi. They 

 were originally classified as a sub-family of the Scolytidae. From a study 

 of the habits and the considerable difference in the structure of the family 

 I have long held the opinion that they should be classed as a true family. 

 In his recent work for the Genera Insectorum Dr. Hagedorn confirms this 

 opinion in that he omits the Platypodidae from his family Ipidae. Colonel 

 Winn Sampson, who has kindly described some of the new species, also 

 treats the Platypodidae as a distinct family. 



So far as present observations have been conducted, the Platypodidae 

 would appear to be entirely wood-borers. The Indian species known all 

 tunnel into the wood of trees to oviposit, the eggs being deposited at the 

 bottom of the tunnel either in the sapwood or heart-wood of the tree. The 

 beetles may be considered as semi-diurnal, since they are often to be found 

 tunnelling into the tree in the daytime, fly well in sunlight, and have a 

 habit of coming up to the orifice of their tunnel in the bark and protruding 

 the head, possibly to obtain fresher air. They remain alive for some time 

 after the eggs are laid and have hatched out, and often die in the upper 

 part of the tunnel in the portion made in the bark, thus blocking the tunnel 

 to the entry of predaceous foes. The larvae resemble in habits those of 

 the scolytid wood-borers who are " ambrosia " feeders, as they invariably 

 appear to feed upon the sap in the walls of the egg-tunnel or on fungous 

 growths growing in this sap. 



The family appears to have a wide distribution 



throughout India and Burma, both in the mountains 



and plains, and probably includes a considerable number 



of species. In m}- book on Injurious Insects of Indian 



Forests, published in i8gg, I could only record one 



species of this family, reported as infesting oak-trees 



in the Himalaya, as a forest pest, viz., Diapus impressiis, 



Janson. In this chapter I deal with nineteen species, 



of which eight are new to science, which oviposit 



in timber trees in different parts of the country and 



about whose life histories some data have been jr,(. .gg 



collected. The family would appear to be one of Crossotarsus coni- 



economic importance in the tropical and sub- tropical -^f'^^' ^^fj*;' '" 

 r , ^ ^ deodar. Western 



forests. Himalaya. 



Q Q 2 



