COCONUT PLANTER'S MANUAL. 37 



which it makes. The beetle itself rarely causes serious injury to coco- 

 nut palms in Ceylon, since it is not known to breed in healthy nalins, 

 and since it appears to be controlled to some extent by its natural 

 enemies, but its importance as a pest is mainly due to the fact that its 

 injury is often followed by the attacks of the Red Weevil, which lays 

 its egis in the wounds made by the Black Beetle, and the grubs of 

 which kill young palms and seriously injure the older bearing palms. 



The results of the damage done by the Black Beetle may be seen 

 in the ragged appearance of the leaves or fronds, which are often 

 badly notched, sometimes on both sides. Or the leaf stalks may be 

 pierced with large holes near the base so that they sometimes break in 

 high winds. This characteristic notching of the leaves and piercing of 

 the leaf stalks results from the beetles having bored through portions 

 of the young leaves and leaf stalks while these were still closed up 

 within the heart of the palm crown. Again, older palms may often 

 bear permanent scars or pits on their trunks as the result of past injury 

 to the crown of the palm by the Black Beetle. 



A Declared Pest. 

 The importance of the Black Beetle as a pest of coconuts in 

 Ceylon has been realized for many years, and it was declared a pest 

 under the Ordinance as far back as 1997, but, apart from the collection 

 and destruction of the beetles, no serious attempt has been made to 

 reduce its numbers ( It is hoped that a fuller knowledge of the habits 

 of this pest may lead to a more general interest being token to keep 

 it in check. 



Life-History and Habits of the Different Stages. 



Beetle. — The Rhinoceros or Black Beetle is a rather large dark 

 brown to blackish insect (figure 1), with a horn projecting slightly 

 backwards from the top of the head- This horn is usually longer in 

 the male (figure 2) than in the female (figure 3.^ The mouth parts 

 are not formed for biting and chewing, as in niauy other beetles, but 

 the jaws are adapted for chiselling out small pieces of fibre and pith 

 while the beetle is forcing its way into the heart of the palm crown. 

 The horn is used in tearing out the fibrous strands which are gradually 

 pushed out as the beetle works its way in. The beetle, therefore, does 

 not bite off, chew, and swallow portions of the palm tissues, but bores 

 into the softer parts of the bud and sucks up the sap as it flows from 

 the wound. The beetles are active about dusk and after dark, but 



