Vll. 



36. Aspidiotus hartii, Ckll., was found on the roots of Discorea or yam. 

 This scale covers the yam roots very plentifully when they are stored for 

 any length of time ; but it does not appear to injure growing plants, 



37. Aspidiotus dictyospermi, Morg., was found on leaves of Areca 

 catechu growing in pots in some quantity in the Nursery grounds of the 

 Botanic Gardens. 



39. Aspidiotus destructor, Sign., is common on the leaves of Bassia 

 latifolia which it covers, and evidently does great harm to the plant. 



40. Aspidiotus articulatus, Morg., was found at the Railway Station at 

 Port-of-Spain on the leaves of lime. When this insect together with Mijti- 

 laspiis citricola and Cldonaspis citri attack the trees at the same time, 

 something must be done to decrease their numbers or the trees will surely 

 succumb. 



The scale insects until late years were but little studied, and agricul- 

 turists as a general rule only know them as " blight." Study of them 

 has however resulted in providing information to the cultivator showing 

 how they may be destroyed or how their ravages may be restricted 

 and in some cases their attack entirely overcome. There is however, yet, 

 much to be learnt. They have their natural enemies as well as other classes 

 of living organisms, and it will probably be found that by maintaining the 

 proper balance of natnre with regard to these as far as possible, that their 

 attack on any particular plant may be reduced so as not to be practically 

 any important hindrance to the agriculturist. 



It is a well known fact that a low state of vitality tends to induce 

 attack, and that when once such pests obtain headway it is very difficult to 

 reduce their nimibers except by the use of destructive agents such as the 

 various washes and sprays that are now in common use. No reliance can 

 however be placed upon these sprays, &c., as real extermmators, and unless 

 the general health and economy of the plant is properly attended to the 

 attack will most surely recur. The cultivator's aim therefore, should be 

 first to destroy the insects, then to clean, and to keep clean the plants, and 

 see that they get all that they require in the way of protection, drainage 

 manure and general cultivation. 



J. H. HART. 



26th December, 1895. 



