298 



THE AGRICULTURAL NEWS. 



September 23, 1905. 



INSECT NOTES. 



Citrus Pest at Montserrat. 



It has recently been reported that the citrus plants at 

 the Grove Station, Montserrat, have been suffering from the 

 attacks of a beetle, vhich eats the leaves. In the absence 

 of a detailed descrii-tion, it is inferred that the report refers 

 to the giejish weevil (Ejiicaerus ravklu^), which has for 

 several years been known to eat the leaves of young citrus 

 plants at the Grove Station. This insect occurs on limes at 

 Dominica, Antigua, and St. Kitts, as well as in most parts 

 of ^Montserrat, but has not, so far as is known, been con- 

 sidered a pest on any but young trees. The life-history is 

 not known, but the larva is most likely a root-feeder, as in 

 other nearly related species. 



Handpickiug is perhaps the best remedy, although, if 

 the weevils occurred in large numbers, they might be jarred 

 off into a cloth such as that described in the Af/riculliiml 

 i\V(.;'s (Vol. Ill, p. 394). This method is used in Porto Eieo 

 in controlling the orange weevil {E.roj>thalmus gpeii</h)-i), 

 which is closely related to the species in Montserrat. 



Beneficial Insects in Cotton Fields. 



In a recent number of thu A:/>-k-ii!tt'.ni/ Xii'-^ (\ ul. I^ , 

 p. 266) descriptions were given of the cotton aphis and the 

 insects that feed upon i't. The cotton aphis sometimes 

 occurs in great numbers on the leaves of the cotton plant, 

 and as ea'ih individual lives by sucking the juice of the 

 plant, considerable injury may result to the plant. The 

 aphis is, however, generally held in check by beneficial 

 insects. These insects are predaceous in their habits and 

 voracious feedeis, each individual eating a large number of 

 aphis each day. 



Unfortunately, cotton planters do not in all cases 

 recognize these insects, and it is in the hope of creating 

 a better understanding as to the useful insects found on the 

 cotton plants that this matter is again referred to. Quite 

 recently, a report was received at the office of the Imperial 

 Department of Agriculture from a planter to the effect that 



his cotton was being 

 seriously attacked by 



I 



several small insects, 

 the worst of which 

 was a small, red bug. 

 A visit to the field 

 in company w ith the 

 planter revealed the 

 fact that the small, 

 red bug complained 

 of was the red lady- 

 bird {Ci/cloneda sa)t- 

 ffuinea), fig. 20, L 

 Another was the 

 spotted lad_v-bird 

 (^MeoiUa mrindata), 

 fig. 20, a. Both thc.'-e were very abimdant, the red lady-bird 

 occurring in numbers on nearly every plant. The larvae of 



<:ilOO 



Fig. 20. Lady-bikds. 



, Spotted lady-bird {Me-jUht maaihilo) ; 

 Red lady-bird (CiiclnHeihi saiijfH.'jieo) ; 

 c, Eggs of lady-biitl. All eidarged. 



as 



Fiv 



Fly. 



these insects were also present, and lastly the lace-wing fly 

 {Cltriisojxi sp.). An energetic warfare had been instituted 

 against all these insects, a large number of them having 

 already been killed. The only evidence against them was 

 that thej- were numerous and that the leaves of the plan 

 showed signs of having been eaten 



So thoroughly had these friendly insects done their worl 

 that very few aphis were to be found. The holes in ther' 

 leaves had been made by 

 the cotton worm, but at that 

 time verj- few worms were 

 found, and no other leaf- 

 eating insects were to be 

 seen, in consecjuence, prob- 

 ably, of the fact that these 

 fields had received an 

 api'lication of Paris green 

 a few days before. The 

 fears entertained by the 

 planter that his cotton 

 plants were being 

 destroyed by the insects 

 he reported were entirely groundless. The role [ilayed by 

 each of these beneficial insects was carefully e.xplaiued, and 

 that particidar planter will not again waste time and money 

 in trying to exterminate from his cotton fields his insect 

 friends. 



C)f the lady -birds the red one is generally much more 

 numerous than the spotted one. It is of a blood-red colour, 

 about I inch long and i inch wide. The spotted lady-bird 

 is of a pinkish-red colour writh black spots on its back. It 

 is longer and narrower than the red one, a little more than 

 I incli in length and about J inch in width. The larvae of 

 these two species are much alike (see fig. 22, c), the eggs 

 being also much alike. The eggs are small, oval, orange-red 

 in colour, and are to be seen on the leaves of the cotton plant. 



The lace-wing (see fig. 2l) is a small, green insect with 

 gauzy wings. The body is about i inch long, and the wings 

 spread nearly an inch. These insects may be seen flying 

 about in the cotton fields or walking about on leaves or 



21. Lace-wi><. 

 (Enlarged.) 



I 



Fig. 22. Eggs .and Lakvae. 



f(., Eggs, and h., larva, of lace- wing fly ; c, hu-va 

 of ladv-bird. AU enlar«ed. 



stems. The larva or grub is small, pointed behind, and is 

 armed with a pair of long, strong jaws. The eggs of the lace- 

 wing are small, white objects attached to a long stalk. 

 (See fig. 22, a. and h.) 



It is very important that these insects should be 

 recognized by planters as beneficial and that they should not 

 be killed They do not eat the leaves nor in any way 

 injure the plant. 



