DISEASES OF THE DATE PALM. 135 



Rhinoceros Beetle or Black Palm Beetle (Oryctes 

 rhinoceros). 



94. The pest is reported from Ceylon, Madras, Malabar, 

 Bombay, Kanara, Bandra, Bengal, Tenasserim, Maliwon, Siam, 

 Annam, Singapore, Pahang, Sumatra, Java, Celebes, Ceram, 

 Amboyna, Philippine Islands, Formosa, Korea, and Hongkong. 



It is said to do a great deal of damage to the toddy palm 

 (Phcenix sylvestris] in Bombay, Madras and elsewhere in India. 

 It has not yet been found in the Punjab, as far as I know, but as 

 the work of observation on the diseases of the date palm is only 

 starting here and the attacks of tha red weevil (see page 126) 

 are frequently associated with this pest elsewhere, it is possible 

 that they are so in the Punjab, although this has not yet been 

 proved. The few remarks made heue regarding it are therefore 

 made to help the people to recognise it and report to us if it 

 should be found. 



It is a dark brcwn beetle about 4 cms. long and having a 

 prominent structure on its head resembling the horn of a rhino- 

 ceros, therefore the name (see illustration No. 47, page 134&). 

 The elytra (hard wing cases) are marked by lines of closely placed 

 annular punctures, one of these lines being close to where the 

 two elytra meet on the insect's back, and three pairs of other 

 lines rather wide apart. The tibia (longest segment of leg visible 

 as the beetle walks) in each of the front pair of legs has four teeth 

 along one side, the uppermost one of these being small. On 

 the other side of the tibia and at its lower end, there is also a 

 short and conspicuous tooth. The tibiae of the middle pair 

 of legs are much shorter than those of the hind ones. 



The beetles are reported to appear after winter and the 

 majority of them about May ; the greatest damage being reported 

 about the time of the rains. 



The usual mode of attack on palm trees is for the imago 

 (mature beetle) to bore a hole 1 inch or more in diameter through 

 the opening leaf-bud or stalks of the leaves into the succulent 

 top of the stern. They are believed to feed on the soft tissues 



