THE COCCIDAE OF SOUTH AFRICA. — in. 227 



of two + even lobules, shorter than L 2 . P strong, dagger-shaped ; usually entire, 

 but occasionally divided at their extremity (fig. 145). Parastigmatic glands numerous 

 at the anterior spiracles, where usually about 15 are arranged in an anterior crescent- 

 shaped group. Circumgenital glands in 5 large groups : — 



6—25 

 13-49 13-49 



10-41 10—41 



Formula : L 13 IP.,, G, 11 2 , P 3 , G, L 3 , P 4 . 



Historical Note. The following interesting note appears in Mr. Lounsbury's 

 Annual Eeport for the year 1898, pp. 32-34 : — 



" Strange behaviour of Peach Scale in St. Helena. — It is possible that an efficient 

 check for our white peach-scale (Diaspis amygdali) exists at St. Helena. The basis 

 for this conjecture is the recorded statement that a century ago the peach trees 

 of the island suffered greatly from the attacks of a white scale-insect which has 

 since wholly disappeared from notice. Kirby and Spence, writing in 1815 (page 113, 

 seventh edition), thus speak of the pest : ' A coccus, as it should seem from the 

 description, imported about thirty years ago from the Mauritius or else with the 

 Constantia vine from the Cape of Good Hope, has destroyed nearly nine-tenths of 

 the peach trees in the Island of St. Helena, where formerly they were so abundant, 

 that, as in North America, the swine were fed with their fruit. Various means have 

 been employed to destroy this plague, but hitherto without success.' Reference 

 is made to an older work, ' Description of the Island of St. Helena,' from which the 

 information was probably derived. I have not had access to this second book, but 

 in Melliss's ' St. Helena,' published in 1875, is a long extract from it, in which the 

 insect is described in such terms as to leave little doubt in my mind that it was the 

 scale now known as Diaspis amygdali. The pest is said to settle on the trunk of the 

 ~tree and to there form a white crust, a peculiarity that at once brings our white 

 peach scale to rnind. Continuing, the old writer, as quoted by Meliss, says : ' It 

 attacks other trees, particularly the native gum-wood trees and the mulberry, but 

 the trunk of the peach seems to be its favourite lodgement.' Next to the peach, 

 the mulberry suffers more than any of our other trees from the present-day scale. 

 Melliss in his work, after relating what a severe pest the insect was formerly, goes 

 on to state that the peach trees of his day enjoy immunity from the trouble, and 

 expresses the belief that the pest had run its course and then naturally disappeared 

 from the Island, a fate which he intimates had also befallen other introduced insects, 

 notably the death's head moth, Acherontia atropos. It seems to me, however, that 

 some trace of the scale must still exist, and associated with it a powerful natura 

 check. Through the kindness of friends, the subject has been brought to the notice 

 of his Excellency, the Governor of the Island, and he has written to say that diligent 

 search will be made in the old gardens, and that should any insect answering the 

 description be found, specimens will be forwarded to me. The result of the enquiries 

 is awaited with much interest, but even should no occurrence of the insect be located, 

 I would not think it conclusively shown that the insect is now extinct, for a few scales 

 here and there would probably be overlooked by anyone not experienced in searching 

 for this type of insect. It may be remarked that Diaspis amygdali is known both 

 at the Cape and Mauritius, the one or the other of which countries, as stated above, 



(C507) d2 



