106 MISS EMBLETON ON CEEATAPUIS LATAISIiE. 



I forget if I sent him specimens or only described the insect : he 

 replied that what I had found were probably females. I found 

 these winged females were not nearly so common as the 

 apterous ones, still at various times I must have found a hundred 

 or so. I think I noticed this insect in its different conditions two 

 or three years, and then my uncle got a new head-gardener and 

 Cerataphis vanished, and I saw it no more." 



Mr. Saunders also kindly sent me some drawings made in 

 1879 of the winged female, and some details of structure, similar 

 to those that have already appeared in Buckton's work : in 

 addition there are also some figures of the nymphal condition, 

 one of which I have added to Plate 12 (fig. 6) as no previous 

 illustration of this instar has been published. 



On March 11th, 1903, Mr. Saunders wrote to say that 

 " On carefully examining some dried specimens of CeratapMs 

 latanice which I had mounted on card, I noticed what I do not 

 think had ever been discovered before, that the apterous female 

 has cornicles ; Buckton has not noticed them evidently. You 

 do not show them in your drawing, and I certainly never saw 

 them in the specimens I examined when fresh. I have just 

 made a drawing under the camera lucida, which I enclose with 

 my other drawings." I find this discovery of Mr. Saunders is 

 correct, and I have added sketches of the cornicles as they exist 

 in the adult (PI. 13. figs. 7-9). Neither Mr. Sau.nders nor I 

 have found them in the young larvae; he says " they are not in 

 the winged forms, but are present in the pupae." 



The occurrence of the winged female in England for one or 

 more seasons twenty-four years ago is of considerable interest 

 in connection with the peculiar life-cycle of this creature, and, 

 on the whole, lends, it appears to me, additional support to the 

 view I suggest, viz,, that the extent of life-cycle, or the number 

 and variety of the instars that go to make up the life-history 

 of this creature, are determined by the conditions under which 

 they live. 



BiBLIOaEAPHY. 



1. HuxLET, T. H., 1852, Upon Animal Individuality. P. E. Inst. 



i. pp. 184-9. [Foster & Lankestek, Scientific Memoirs of 

 Thomas Henry Huxley, p. 147 (London).] 



2. Spenceb, H., 1864, Principles of Biology. (London.) 



