9 



It is not proposed in the present article to discuss the measures which should be taken to prevent 

 the introduction of pests; whether there should be a government quarantine, or the matter should be 

 left to the public spirit and good sense of private individuals. It would undoubtedly be a matter in- 

 volving a certain amount of trouble and expense, to inspect all imported plants and rid them of 

 insects, but when it is considered that a few shillings thus spent to-day, may save us from a pest 

 which would cause the loss of perhaps hundreds of pounds annually for an indefinite number of years, 

 the subject appears to deserve serious consideration. No doubt, as in the case of human maladies, 

 there will be an occasional leaping of the bounds in spite of much care, but that is no reason for utter 

 recklessness. 



Importing the Enemies of Coccidae. 



As a general principle, it is extremely unwise to disturb the balance of nature. The importation 

 of new animals, whether mammals, insects, or what not, is a risky business, very generally attended 

 with unfortunate results, as we in Jamaica have excellent reason to know. But when we have already 

 upset nature's arrangements by introducing foreign Coccidae without their enemies, the best remedy 

 is to search out those enemies, and introduce them too, as in the case of the Vedalia. Even in such a 

 case, however, care is needed, to ascertain very exactly the habits of the enemy we are importing. It 

 was true enough that the mongoose fed on rats, but it also feeds on poultry and wild birds. The 

 European sparrow, taken to America, has no doubt some virtues, but if the introducers of that bird 

 had had a proper knowledge of its habits, they would have been horrified at the idea of inflicting so 

 serious an injury on their country as has resulted from their actions. 



Fortunately, however, there are some enemies, including all those really important in connection 

 with Coccidae, which we can import with perfect impunity, as their habits are well-known, and there 

 is no reasonable possibility of their proving injurious. Such are the lady-birds, and the parasitic 

 Chalcididce and Hymaridce. If we had an extensive Cochineal industry at some future time, it is possible 

 that some of these enemies might attack the dye-producing insect so as to interfere with the value 

 and amount of the product, but there seems no likelihood of such an event, and even were it to so 

 happen, the saving to other crops would much more than counterbalance the loss in this direction. 



The present writer has lately made some studies of the fauna of Jamaica, the results of which when 

 more complete, will appear elsewhere. The general conclusions arrived at are, that we have two distinct 

 faunae in this Island ; one, very ancient and dating back to the time of connection with the continent ; 

 the other, of more recent origin, consisting of species which have reached us from over the sea. The 

 former contains few species, and these highly peculiar, — often representing genera now found nowhere 

 else. The latter includes species either identical with, or very closely allied to, those found elsewhere, 

 In that grand genus of butterflies known as Papilio, P. homerus and P. thersites belong to the old 

 fauna, and P. poly crates and P. thoas to the recent. 



The majority, at least, of the destructive Coccidae in Jamaica are allied to or identical with 

 Bpecies found elsewhere, and consequently they must be classed with the recent fauna which has come 

 over sea — in this case no doubt in ships. 



The importance of this appears when we consider that if the parasites of the Coccidae have not 

 been imported with them, there will be nothing ready to attack them here. In the United States, if 

 you import a Lecanium or an Aspidiotus, there is almost sure to be a parasite of an allied native scale 

 that will attack it ; but in a case where there are no allied native scales, there will probably be no 

 available native parasites. Such Chalcids, &c, as belong to our ancient fauna, probably will not attack 

 introduced CoccidaB to any great extent ; while we are not likely to have any suitable recent fauna para- 

 sites until after the advent of the scales, since if by chance a Chalcid came to us over sea, it would 

 find nothing in which to propagate its species. 



Some of our imported scales, as will be explained in detail when the species are discussed, are in- 

 fested by parasites. For example Mytilaspis citricola, an injurious orange scale, is infested both in 

 Jamaica and in Antigua. But so far as I have been able to observe, the Jamaica Coccidae have few 

 enemies, and to this, in large part, is probably to be attributed their great abundance. It is hoped, 

 at some future time, to introduce some of the Coccid-enemies that are likely to be useful, but of this 

 more hereafter. Prof. C. V. Riley, who is more competent than anyone else to judge of such a matter 

 writes (March 25, 1892) : " I think it would be an easy matter for you to import the parasites of any 

 particular scale which may be common to Jamaica and this country, and I will gladly help you when 

 opportunity offers." 



How xo send Scale-insects by Post. 



Later on, it is proposed to treat of the various species separately and in detail. In the meanwhile, 

 the writer will be very glad to receive Scale-insects from any part of Jamaica or the West Indies. 

 They are as a rule extremely easy to collect : all that is necessary is to cut off some of the infested 

 leaves or twigs, and put them in an envelope, writing on the outside the name of the plant, the esti- 

 mated severity of the attack, the locality, and the name of the collector. Such envelopes may be 

 enclosed in a larger one, and sent by post in the ordinary way. Species that are soft, or liable to be 

 damaged, can be sent inside a small joint of bamboo, or any convenient receptacle. It is better not to 

 put the specimens in any air-tight box, especially if the leaves are fresh, as they are liable to rot. 



Any specimens sent will be duly acknowledged and identified, and proper credit given in publi- 

 cation. They should be addressed to the Curator of the Institute of Jamaica, Kingston. 



June 18, 1892. 



