]72 r January, \ 



ON THE SPECIES OF THE GENUS ORTHEZIA. • 



BY J. W. DOUGLAS. 



Two years ago, Mr. Henry Chichester Hart sent for my inspectioj 

 examples of an Orthezia he had found in Ireland, saying that the 

 appeared to him to be identical with a species he obtained at DisJj 

 North Greenland, which had been named for him Dorthesia chitov 

 Zett., that it also seemed to be the same as Coccus cat aphr 'actus, Shaw 

 and requesting my opinion. My reply was that I believed it to I 

 Orthezia Signoreti, F. B. White, that it seemed to agree with til 

 species described by Shaw and Zetterstedt, and that both these lata 

 and several others had been referred by Signoret, the latest writer c 

 the subject, to Orthezia (Ajihis) urticce, Linne. An article in tl 

 " Entomologist " for November, by Mr. Hart, on Dorthesia chiton, h; 

 been read by some of my correspondents to mean that I agreed will 

 Signoret's conclusion, but I merely stated a recorded fact, not havii' 

 at that time investigated the question. It w r ould be superfluous nol 

 for me to say this, but that it gives me the opportunity to offer sod] 

 remarks indicating that two species are confounded under the narif 

 urticce. These remarks were prepared long since, but reserved, becaul 

 Mr. W. E. Kirby informed me that Mr. Hart intended to work o I 

 the matter thoroughly. 



The species of this genus are dimorphous, that is, as in othj 

 Coccina, the males only are winged in the imago state. The followal 

 is the substance of Signoret's summary of the peculiarities in tl 

 natural history of the apterous forms (Essai sur les Cochinelles, a 

 421) — particulars it is essential to know : 



" "We find examples having six joints in the antennae, these are the young larv I 

 others with seven joints, more or less equal in size ; others, also with seven join! 

 with a kind of scape, as in the Hymenoptera ; finally, others with eight joints, thl 

 being the adult females. The individuals with seven joints have a peculiarity til 

 we have not seen in any other genus (those in which the joints are of regular foj 

 are the female larva?), namely: that those with the scape have in all the legs i 

 tibia and tarsus united, and thus form but a single joint. It is not, therefore, wonc 

 ful that authors have indicated a certain number of species, which, up to this till 

 we have not been able to find in the many places where we have collected thl 

 insects." 



Of the apterous forms two kinds exist, for while in both the wh-l 

 body, above and below, is covered with a close-fitting, wax-like (9 - 

 noret calls it calcareous), white secretion, and in both there is a wil 

 raised, segmented border formed of this matter, there are yet two gr<|| 

 differences, constant throughout all the stages of life, in the other dfl 



