﻿iig 



ORNITHOPTERA ARUANA, v. Obiensis. 



As I have been quite unable to ascertain in what pub- 

 lication this insect has been described, and by whom, and 

 also its name, though I have been assured that it has 

 been described by a Dutch Entomologist, I have thought 

 it best to provisionally propose the above name, v. Obiensis, 

 so as to prevent further delay. Later on, if I obtain the 

 required information, I will acknowledge it, when the above 

 name may or may not, become a synonym. 



S . Anterior wings : deep velvety black, with a discal 

 warm brown pupseform sexual mark ; the subcostal colour 

 band is silvery greenish azurine blue, rather broad uniform- 

 ly, extending from the base to the apex of the wing ; the 

 interior submarginal band of the same green extends from 

 the base till half way up the outer margin of the wings, 

 when it becomes divided into three twin spots to within a 

 little distance from the apex, the highest spot small and 

 composed of bluish-green atoms ; the median nervure 

 slighty indicated by a line of bluish atoms, otherwise the 

 neuration is only obscurely to be seen. 



Posterior wings of the same greenish blue, the veins, 

 other than the subcostal and median, only faintly seen ; a 

 few delicate black hairs flow from the base into the cell 

 a little below it, and a few black atoms are equally scater- 

 ed over the wing, but can only be seen by examining the 

 wing closely ; there are 8 lemon-orange internervular spots 

 (nearly obsolete) near the outer margin ; and a narrow 

 black submarginal border ; the abdominal marginal fold 

 is dark brown. [Viewed obliquely opposite the light, 

 the left lower wing becomes a brilliant silvery azure blue, 

 with salmon coloured reflections, and the colour band of 

 the anterior wing silvery green ; opposite the light, in the 

 ordinary way, the wings are warm bluish silvery green ; 

 viewed against the light the wings become lilac, and slight- 

 ly saffron green; obliquely they are entirely suffused "with 

 silvery salmon tints.] The longitudinal thoracic mark 

 the same colour as in the wing. 



Undersurface of anterior wing, with the transverse discal 

 colour marks silvery azure-blue on the lower three, 

 and all the others to the sub-costa silvery olive green ; the 

 distal end of the cell on its lower half with a moderately 

 large green spot, extending nearly half way towards the 

 base, and there is a short elongate and green congeries of 

 atoms close to the submedian nervure, midway of the cell. 



Under surface of the posterior wings golden green, but 

 with the lower half of the cell, and part of the area 

 beneath the median nervure silvery azure blue ; an elon- 



gate spot of golden yellow between the costal and sub- 

 costal veins ; a transverse band of suborbicular black 

 discal spots, 5 in number, followed by an outer row of 

 golden yellow spots ; the submedian area half-way from 

 the anal angle rich yellow, shading into the blue above ; 

 the abdominal fold vivid brown, and fringe of hairs chest- 

 nut tint. 



[Viewed opposite the light the appearance is nearly 

 normal, or very slightly warmer ; obliquely against the 

 light the colours are subdued, and shot with a saffron 

 yellow sheen, except on the blue ; when the sky is clouded 

 the greens appear olive toned.] 



The abdomen is golden orange yellow as in Eumceus. 

 Length of costa 76, of hind margin 53, and of inner margin 

 35 mms. Greatest length of posterior wing 44, and width 

 35 mms. Length of abdomen or antennae 34, and of the 

 thorax with head 21 mms. 



Habitat: Obi or Oby Major. (Waterstradt). 



Obi is a small island S. of Batjan, or slightly S.W. of 

 Djillolo, in about E. longitude I27°22' to I23°i2' and 

 about S. latitude i° 18' to i° 14'. 



This form, probably a local variety of Aruana, appears 

 to be closely allied to Eumceus, and is another of those 

 transitional links between Aruana and Urvilliana, of which 

 more will probably come to hand in the future. 



The most important difference between Obiensis and 

 EumcBUS is the character of the different blue colours. In 

 Obiensis also the blue extends uniformly over the coloured 

 portions of the wings ; in Eumceus there is a decided patch 

 of green on the posterior wings to below the first subcostal 

 nervule ; there are discal black orbicles towards the outer 

 margin, in Obiensis there are none, but there are two small 

 yellow spots and traces of a third ; and while on the 

 anterior wings the median vein and its branches are well 

 marked with green atoms, only a few blue atomic scales 

 indicate the direction of the median vein in Obiensis. On 

 the under-surface of Eumceus the cell is nearly occupied 

 by the green area, while in Obiensis less than i-4th of the 

 cell is coloured. On the posterior wing of Eumceus there 

 are no submarginal golden spots, but in Obiensis they are 

 fully present. 



In the Tring Museum and other collections. 



