the internal nervure is of a bluish-green with black atoms. 

 The spots on the lower wing are only four in number, 

 nearly oval, and almost of uniform size. The hind- 

 marginal border extends only half wa)^ from the anal angle, 

 the remaining half being only faintly indicated towards 

 the apex of the wings. 



The median and sub-costal nervures are deep-black, as 

 is also the sub-median. All the rest are only faintly seen 

 in the blue. Length of costa 84 ; antennae and abdomen 

 (allowing always for the anal curve) 35 ; thorax 15 ; head 

 (width) 7, (length) 4 mms. ; articulations of antennae, 

 including basal joint, 42 in number. 



This very nearly agrees with the original of my figs, in 

 colour and markings, except that the blue patch within the 

 discoidal cell of the under surface is more extensive, and 

 the blue band on the hind margin of the upper surface of 

 the superior wing is more complete, i.e., not so strongly 

 divided by the nervures, and extends from the anal nearly 

 to the anterior angle. The locality of this specimen was 

 New Ireland. 



From the time of the discovery of this species till 1877, 

 M. Durville's specimens were the only ones known, till 

 the Rev. Mr. Brown, a Wesleyan Missionary, sent a series 

 of both sexes to the collection of Messrs. Godman and 

 Salvin, thereby giving us an opportunity of knowing what 

 the 2 was like. In their paper, in Proc. Zool. Soc., 

 Godman and Salvin say that "the <? 's present a slight 

 amount of variation inter se., one having the characteristic 

 blue markings rather purer than the other, in which a 

 slightly greener tint prevails." This has been the case 

 with many of the specimens which have reached us since : 

 as might be expected they only indicate local variation. 

 The wonder is that this variation is not greater. In 

 addition to the colours which the <? presents on its 

 different surfaces, many beautiful opalescent and other 

 tints can be seen by looking at it from different directions, 

 and in different degrees of light. These, as I hope to 

 show in another section of this work, have a very im- 

 portant meaning. On the 3 from which my figs, were 

 drawn, in certain positions the entire violet-blue band 

 along the costa presents tints ranging from fiery-salmon to 

 richest emerald green ; the blue scales on the lower wings 

 become a delicate fawn colour ; the extremely delicate 

 velvet-black of the upper wings is shot with opalescent 

 violet-green ; the 3 sexual sericeous patch of velvet-brown 

 on the upper wings ranges from sooty black to a very 

 warm -red velvet brown. The underside is opalescent on 

 all the wings, viewed obliquely : the green of the lower 

 wings becomes a fawn-greenish blue, or delicate purple- 

 salmon, and the blue on the upper wings is a fiery-salmon. 

 These are highly suggestive of the colours of 0. Crcesus. 



The following are the measurements of the costa in 

 three specimens belonging to Mr. Janson ; 88, 86, and 89 

 mms. respectively. 



2 . Godman and Salvin, in their paper, gave a short 

 description ; the 2 " resembles that of 0. Priamus itself, 

 being of a sordid brown colour, the lighter markings being 

 also dingy and not well defined as in O. Aruana. In 

 form and position their marks correspond to those of the 

 2 O. Priamus. The anal angle is however more pro- 

 duced, a characteristic also shown in the S ." Proc. Zool. 

 Soc. p. 148, 1877. 



The depth of the brown on the wings varies greatly in 



different examples. In some it is very dark, in others ex- 

 tremely light. The white markings of the lower wings are 

 often so dingy as almost to merge into the brown — this 

 effect being caused by the brown scales which are spread 

 over them, and graduated in number from the base of the 

 marks. The white spots on the upper wings are generally 

 much lighter, and sometimes faintly fawn- tinted, while this 

 tint is more strongly indicated on those of the lower wings. 

 The abdomen is of a burnt sienna yellow, tinged with 

 green towards the thorax, with dorsal triangular cloudings 

 on four of the segments, and small orange-black lateral 

 dots seven or eight in number. On the underside of the 

 wings the white markings are much more strongly tinted 

 with burnt sienna-yellow, especially the outer half of those 

 on the hind wings : all the large semi-orbicular and conical 

 spots enclosed by these are very black, the hind marginal 

 border of the hind wings being nearly as intense ; those of 

 the superior wings are faintly seen through on the upper sur- 

 face. The veins of the wings on both surfaces are rich 

 brown-black. The under-side of the abdomen is orange- 

 yellow, reddish at the anal extremity, with heavier black 

 dots, and black on the subdorsal articulations ; the sides 

 of the breast with a rich vermilion patch occupying all but 

 the lower part near the trochanters; legs and tarsi black; 

 eyes warm brown ; antennae black. Viewed obliquely, and 

 in different positions, all the browns are velvety purple- 

 brown ; opposite the light a ruddy ochreous brown with 

 greenish tints in parts. 



A specimen in Mr. Dannatt's collection is much lighter 

 in colour. The upper wings are white brown, with a faint 

 green tinge ; lower wings white brown with ruddy tinge ; 

 underside of upper wings slightly darker with ruddy tinge, 

 but changing like shot silk as the insect is moved about ; 

 lower wings light reddish ochreous-brown except on the 

 spots and band. Expanse of costa 104 mms. 



Four 2 2 In Mr. Janson's collection, expanse of costa 

 87, 97, 105, 106 mms. respectively. 



? In Brit. Mus. Length of costa 100 ; length of 

 antennae and abdomen 44 ; of thorax 15 ; of collar 4 ; and 

 of head 3 mms. Width of head 7 mms., divided by the 

 eyes into three nearly equal parts. Width of collar 7 

 mms. ; probable width of thorax 11 mms. 



The groundcolour of this specimen on the upper side is 

 much paler than in my fig., especially of the superior wings. 

 The spots within the white of the inferior wings are much 

 smaller. Length of legs : first pair; femur, 13; tibia, 9; 

 tarsi, ig mms. Second pair ; femur, 14 ; tibia, 16 ; tarsi, 

 18 mms. Third pair ; femur, n ; tibia, 15 ; tarsi, 20 mms. 



Specimens from which the plate was drawn — Habitat, 

 3 New Ireland ; 2 Solomon Islands, (but which of them 

 I could not learn). 



The number of articulations in the antennae of Mr. 

 Crowley's 3 are 46 ; of his 2 56 ; of Mr. W. Dannatt's 

 2 50, though it is a larger specimen, — the length of the 

 costa of the former being 99, and of the latter 104 mms. 



The abdominal fold of the 3 is more open and simple 

 than in the $ $ of the Pompeoptera ; and does not enclose 

 a cottony deposit. [The sexual brand, or sericeous 

 pupseform transverse patch take the place and function of 

 the latter in the true Ornithoptera, probably.] The fold 

 of the 2 is almost obsolete, or only presenting a concave 

 depression. 



