226 

 COCCID^, OR SCALE INSECTS. 



By T. D A. CocKERELL, F.Z.S., F.E.S., Curator of Museum, 

 Institute of Jamaica. 



(From the Jamaica Botanical Department Bulletin.) 



Mr. Bowrey and other observers have noted that -weakly 

 plants are those usually attacked, strong ones escaping. It would 

 often be difficult to prove this, as if the facts are stated another 

 way, namely that the plants attacked are weakly, we have but a 

 truism. Nevertheless, it is apparently well-ascertained that 

 plants sufl'ering from other causes do especially harbour scale- 

 insects, and i]i any case it is perfectly evident that given the 

 same amount of insect-injury in any two cases, the plant which 

 was also injured in some other way v.'ould soonest die. 



As an instance of the severe vv'ay in which some plants are 

 attacked, we may take the genus Citrxis, which includes the 

 orange, lemon, &c. These trees ai'e attacked in America by four 

 or five species of Aspidiotus, one Chionaspis, one Parlatoria, two 

 of Mytilasjns, two of Cero2'>lastes, one JDacfylopius (mealy-bug), 

 one Icerya, and three of Lecanium. Of these 14 citrus-scales, 

 eleven appear to be found in Jamaica, though not all as yet on 

 Citrus. 



The special injury done by the several species will be dis- 

 cussed later on. 



While blaming the Coccidse for their injuries, it must be 

 remembered that certain species are very viseful. We have one such 

 in Jamaica, the Cochineal Insect (Coccus cacti), which abounds 

 on the Opuntla in the Parade Gardens, Kingston. 



(To be Confimied.) 



