136 Transactions. — Zoology. 



year was extraordinarily mild and dry. This disappearance 

 of theirs was, indeed, so sudden that, whereas in July, when 

 procuring specimens of male pupae for hatching, I could have 

 carried away untold thousands, in August I could scarcely 

 find any, and had to hunt over a good deal of ground to pro- 

 cure a dozen infected leaves of Melicytus. I cannot offer an 

 explanation of this peculiar invasion and departure. A similar 

 circumstance, but in a much less pronounced way, was noticed 

 by me in 1879 in the case of Lecanium hespcrichim (see 

 "Trans. N.Z. Inst.," vol. xii., p. 292) : that insect, in a dry 

 season, had become considerably lessened in numbers ; but its 

 appearance and disappearance were not by any means as 

 peculiarly rapid as those of C. dysoxijli in 1889. 



The second and much more curious fact in connection with 

 the insect is the emergence of a number of apterous males. 

 I had not the male of the species before this year, but, finding 

 the male puparia on Melicytus so numerous, I collected many, 

 with a view to procuring the adult. The result was that I was 

 able to hatch them out as follows : In February, four : in 

 March, eleven ; in May, eight ; in June, sixteen ; in July, eleven ; 

 and in August, two. I was particular in taking note of the 

 numbers at the time I procured them, because the occurrence 

 of an apterous male at once arrested my attention ; and for 

 the same reasoii I am particular in recording them now. I 

 know of no similar instance amongst Coccids of any group : no 

 observer has, I believe, recorded the existence of an apterous 

 male, unless the extraordinary statements of M. Moniez 

 (" Comptes Eendus de I'Acad. des Sci.," February, 1887), 

 regarding males of L. liesperidum existing within the abdomen 

 of the females can be accepted as positive. All male Coccids 

 have hitherto been considered as having two wings : there is a 

 case reported by Dr. Signoret ("Essai," p. 320) of Gossyparia 

 ulvii, where the male has "rudimentary elytra," but Signoret 

 himself doubts whether the insects he saw were really adult.''' 



* In the August, 1889, number of Professor Riley's excellent publica- 

 tion, " Insect Life," which has just reached me, !irr. L. 0. Howard gives a 

 very full description of Gossyparia tihni, which seems to have lately 

 invaded European elms in America ; and he figures both the male with 

 rudimentary wings mentioned by Signoret, and the fully-winged male 

 which also emerges from the cocoons. It seems, therefore, that G. uhnl 

 and C. dijsoxyli are two insects with abnormal males ; the difference 

 being that in G. uhni males with rudimentary wings emerge only " a few 

 days," according to Mr. Howard, before the fully-winged forms, while in 

 C. dysoxyli males entirely wingless emerge for several months before the 

 winged forni appears. 



While this paper is in the press I have received a note from Jlr. 

 Newstead, of the Grosvenor Museum, Chester, England, stating that he 

 has bred both apterous and winged males of Chio7iaspis fraxini. Perhaps, 

 now that attention is directed to the point, other observers may note 

 similar occurrences. 



