61 



NOTES ON INSECT PESTS IN ANTIGUA. 



By H. A. Ballou, M.Sc. 

 Entomologist to the Imperial Depart meat of Agriculture, British West Indies. 



(Plates VIII and IX.) 



The principal object of my visit to Antigua, during December 1912, was to 

 study an outbreak of the twig borer of limesf which had been reported by the 

 Superintendent of Agriculture from two localities in the island. 



At the time of my visit, owing to recent pruning, there were only occasionally 

 infested branches to be seen, but these were in sufficient number to enable me to 

 form a very good opinion of the nature of the attack and of the general habits 

 of the insect. 



The attack on a lime branch apparently always begins on a small twig. I am 

 not able to say whether the twig on or in which the egg is laid is dead or dying 

 at the time of egg-laying ; but in every instance of attack observed by me, both 

 in the field and in specimens forwarded, the twig has been found entirely eaten 

 out, the dead interior connecting with the tunnel in the larger branch from which 

 the twig springs. This branch is always more or less girdled by the tunnel of 

 the grub. The girdling seems to be the first thing done by the grub after com- 

 pleting the destruction of the smaller twig and it results in the death of the branch 

 beyond the point of the girdle. The tunnel does not circle the twig in such a 

 manner as to cut it off completely, but the direction is rather in a spiral, so that 

 as the injury to the branch becomes more and more felt, it breaks down and is 

 usually left hanging. The entire grub and pupa stages are passed within this 

 branch, the adult beetle only issuing from the dead branch some time after 

 emerging from its pupal condition. 



The length of the life-cycle is not known. The number of eggs laid by a 

 single female, and the other food-plants on which they are laid, are also still to 

 be learned. With regard to the length of life-cycle, it may safely be said to be 

 comparatively long, since specimens have been found, both larva and adult, in 

 lime twigs which had apparently been dead for a long time, and it seems likely 

 from what we know that this insect begins to feed in living wood. 



It is possible that this insect has occurred as a pest of limes in Antigua for 

 some time but has been overlooked. It is also probable that it has a considerable 

 range of food-plants from which renewed attacks on limes may be experienced 

 from time to time. The presence of this insect, however, should not, in my 



* [Extracted from a Report submitted to the Secretary of State for the Colonies by Dr. 

 Francis Watts, C.M.G., Commissioner, Imperial Department of Agriculture for the West 

 Indies. — Ed.] 



f [Specimens of this insect have been forwarded for identification by Dr. Francis Watts ; it 

 proves to be Elaphidion mite, Newman, a Longicorn of the family Cehambycidae. The species 

 has also been recorded from St. Thomas, St. Bartholomew, St. Kitts, Guadeloupe and 

 Brazil.— Ed.] 



