323 



Coccids and Aleurodids included a species of Pulvinaria on arti- 

 choke that has apparently not been previously'' recorded from Bar- 

 bados, and Orthezia praelonga, Dougl., Saissetia nigra, Nietn., Coccus 

 mangiferae, Green, Vinsonia stellifera, Westw., Chionaspis citri, 

 Comst., Psendococciis calceolariae, Mask., Aspidiotus sacchari, Ckll., 

 Pseudococcus sacchari, Ckll., and Aleurodes goyabae, Goldi, on various 

 fruit trees and garden plants. Selenaspidus articulatus, Morg., 

 was frequently found on Tamarindus indica, and was apparently 

 checked by the fungus Hormodendron sp. Coccus viridis. Green, 

 abundant on Citrus, was sometimes successfully controlled by the 

 fungus, Cephalosporiiim lecanii. The Chalcids, Aspidiotiphagus citri- 

 nus, Craw, infesting Aulacaspis rosae, Bch., and Encarsia sp. attacking 

 Aleurodes goyabae, Goldi, exercised a considerable measure of 

 control. 



Special investigations into the life-histor\^ of Lachnosterna {Phytalus) 

 smithi, Arr., under Barbados conditions, are recorded at length. It is 

 estimated that the loss due to this beetle in one year over 1 1 ,666 acres 

 was 7,945 tons of sugar-cane, valued at approximately /33,400. 

 Almost any green foliage is eaten by the beetles, though they seem 

 to prefer leaves of sugar-cane, cassava and roses. Sometimes banana 

 foliage is severely injured. The larvae devour roots of various grasses, 

 particularly sugar-cane, maize, palms, bananas, legumes and rose 

 trees. 



Life-history studies show an average length for the stages as fol- 

 lows : — incubation period 13 days, larvae (active) 227 days, pre-pupa 

 31 days, pupa 17 days, adult life, before emergence. 27 days, from 

 emergence to oviposition 60 days, reproductive period 61 days, post- 

 reproductive period 16 days. The adults fly and feed on the leaves 

 shortly after dusk, remaining underground in the daytime ; the eg§„ 

 larval and pupal stages are all passed underground. As the life-cycle 

 may vary from 308 to 618 days, there is a great overlapping of 

 broods ; the maximum emergence of adults is during May and June, 

 but emergenc<=! may continue until January. The average number of 

 eggs produced by one female was 108. For oviposition and hatching 

 of eggs a certain amount of moisture is necessary; under dry conditions 

 this is obtained by burrowing deeper into the soil. The effect of 

 irrigation has not been studied, but it is thought that the beneficial 

 effect of the green muscardine fungus, Metarrhizum anisopliae, would 

 counterbalance the encouragement to breeding of the humid 

 conditions. Many larvae seem to be killed by a bacterial disease, 

 caused by an organism resem.bling Bacillus pestis. The Scoliid 

 parasite, TipJiia parallela, which was considered to be an effective 

 check some years ago, no longer seems so efficient, neither is Dielis 

 dorsata, F., sufficiently active. The possible effect of certain 

 Nematodes on the eggs is discussed. 



It is suggested that there should be rigorous co-operative action 

 on the part of planters in collecting beetles throughout the year. 

 A central insectary should be estabhshed for the rearing and distri- 

 bution of Tiphia parallela. Permanent ponds should be constructed 

 on estates for the rearing of the common toad, Bufo agua, which is 

 a very useful predaceous enemy of these hard-back beetles. Rotation 

 of crops does much to discourage the insect in infested fields ; cotton 

 is an excellent crop in this respect. Any new parasites of L. smithi 

 that are discovered in the future in any country where the hard-back 

 occurs should be introduced into Barbados. 



(3393) z 2 



