128 FAMILY BOSTRYCHIDAE 



The males and females in some species differ from each other, and also 

 have curious modified characters which distinguish one male or female from 

 another of the same species, due to modifications in the hooks and teeth of 

 the prothorax and tubercles of the body. 



The larva is white, curved, corrugated, soft and flesh}', furnished 

 with powerful mandibles and a pair of four-jointed 

 Larva. antennae, and three pairs of legs on the thoracic 



sections. 



The pupa (fig. 31, a) is soft, white, with a well-developed hood-like 

 prothorax, the antennae, legs, and wings being pressed 

 Pupa. against the chest. 



The modus operandi of the beetle is to tunnel 

 through the bark down into the sapwood (or in the case of the bamboo into 

 the wall), eating out a gallery of irregular length in which the eggs are laid 

 at intervals. The larvae on hatching eat out irregular galleries running 

 more or less in the long axis of the wood, pupating at the end of the tunnel 

 when they have reached full growth. On maturing the beetle bores 

 through the wood until it reaches an empty egg-tunnel, up which it crawls 

 and escapes to the outside. 



From a utilitarian point of view the family is one of the most destruc- 

 tive in the country, owing to the large amount of harm it does to felled 

 timber and bamboos. This damage is well known, and timber contractors 

 soak their cut bamboos and poles in water and then smoke the former to 

 prevent the beetles from infesting them and reducing them to powder before 

 their sale. This is done throughout the tropics. Also timber contractors 

 will not cut bamboos and poles when the moon is full, as they hold the 

 opinion that bamboos felled at this period are more subject to attack. 

 Elsewhere this subject is discussed in detail (p. 140). That the damage 

 done by the insects throughout the country to constructive material must 

 run into very large figures is borne out by the fact that buildings which 

 include bamboo and pole materials require continual attention and repairs 

 in parts of the country. During the year 1903, whilst officiating as 

 Superintendent of the Indian Museum, I carried out a series of experiments 

 in conjunction with the Head of the Telegraph Workshops at Alipur, which 

 proved that soaking the bamboos in crude rangoon oil rendered them 

 immune to the attacks of Dinodcrus, and bamboos so treated which were 

 used for a light field telegraph on the Tibet Mission, 1904-5, stood the test 

 well and remained unattacked for years afterwards (p. 137). 



It has long been supposed that the bostrychids were wood-borers pure 

 and simple, and did no damage to standing trees. Observations have shown, 

 however, that species of Sinoxylon will attack and oviposit in sickly standing 

 green trees. A worse habit in the case of one species, Sinoxylon crassum, has 

 received some investigation. In February 1902, Mr. A. M. Littlewood, a 

 student of the Imperial Forest School at Dehra, found an insect tunnelling 



