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shot-hole borers and ants, and no advance in methods of control of 

 these insects has been made. May beetles and the sugar-cane root 

 and stalk borers have been important in the cane district. In the 

 Mayanfiiez section there have been outbreaks of the caterpillars of 

 Megalopyge l-rugii, damaging guama {Inga spp., coffee shade trees) 

 and coffee foliage; of Diahrotica innnba and D. biviltata; and of 

 Xgleborus sp., which has killed numbers of guama trees. During 

 the summer PliUella niacnlipennis (diamond-back moth) did some 

 damage to cabbage, but was reduced in numbers when the heavy 

 rains began. There was a local outbreak of the Geometrid. Melan- 

 cJtroia corvaria {cephise), in Camuy, Phyllanthus distichus being almost 

 defoliated. A pate firincisca has been numerous about Mayaguez 

 and has ten recorded host plants. It has been taken in living Salix 

 humbold liana and in dry posts of Picramnia pentandra. The most 

 important work of the year has been in connection with the pests of 

 coffee and coffee shade trees, and with a bacterium pathogenic to 

 May-beetle larvae. Of the remedial measures for the control of 

 Scapteriscus didactglus (mole-cricket) tested at the station, one seemed 

 to give promise of satisfactory results. This was the strewing over 

 infested areas of a mixture of phosphorus and corn-meal. Leucoj)lera 

 coffeella (the coffee leaf-miner) is abundant in coffee-growing sections 

 of the island. The eggs are laid singly on the upper side of the leaf. 

 The larva immediately after hatching enters the leaf tissue ; the 

 larval stage, lasting from 11 to 13 days, is passed entirely within the 

 leaf. Pupation takes place on the underside of the leaf, the adult 

 emerging in from 6 to 8 days. Liberian coffee seems to be free from 

 serious attack. The miner in the larval stage is parasitised by two 

 Chalcids, Chrysocharis livida and Zagmmmosoma muUilineatum. Spray- 

 ing infested trees with 1 pint of nicotine sulphate in 100 U.S. gals, 

 water containing 5 lb. soap in solution, is effective against the pupae, 

 if applied with considerable force to the underside of the leaves, but 

 the i-esults do not repay the expense and labour involved. Spraying 

 against eggs and larvae gives no practical results. Xyleborus sp. was 

 the most troublesome pest of shade trees for coffee, such as Inga 

 laurina and I. vera. In some hill districts large areas of /. laurina 

 were killed. Trees should be felled and converted into charcoal as 

 soon as the beetle is noticed. An undetermined pink Coccus, attended 

 by the ant Myrmelachista ambigxa ramidorum, attacked the branches of 

 guama, resulting in the destruction of new growth and the weakening 

 of branches. The removal of infested branches from isolated trees a few 

 years ago was successful, but constant inspection is necessary. Banding 

 trees with tanglefoot and the use of poisoned bait have been un- 

 successful in ridding trees of the attending ants. The larva of 

 Megalopyge hrngii has been abundant on guama. Coffee, especially 

 the Liberian variety, was also attacked. It is usually parasitised by 

 a Tachinid fly and by Chalcis ovata ; the latter is an important check 

 on this pest. The disease of Lachnoslerna due to Micrococcus nigro- 

 fasciens is confined to the larva. The bacterium is present in the soil, 

 but its efficiency cannot be increased, since infection takes place only 

 through a wound in the iiitegument of the larva. The Arctiid, Ecpan- 

 theria eridanus, was found on orange trees in the Mayaguez district. The 

 ogg-masses are laid on the leaves and hatch out in 5-8 days. The larva 

 reaches maturity in about five weeks. Pupation takes place in a loose 



