20 On don ata from Queensland. 



supra-triangular nervureson the fore wings and the untraversed 

 triangle of the hind wings will at once distinguish it. 



Orthetrum villosovittatum. 



Libellula viUosovittata, Brauer, Verli. zool.-bot. Ges. Wien, xviii. 

 p. 167 (1868). 



The collection contained four specimens of a species which 

 I regard as 0. villosovittatum, although it is less yellow at 

 the base than Brauer's description appears to indicate. There 

 is a supra-triangular nervure, and the triangles of all the wings 

 are traversed, points on which the description says nothing. 



Orthetrum oramineum. 

 libellula braminea, Fabr. Ent. Syst. Suppl. p. 284 (1798). 



This species is very common throughout Australia, and the 

 description of Fabricius would apply very fairly to the female 

 or immature male. I have therefore added a more full 

 description of the adult male. If I have correctly identified 

 Fabricius' insect, it is a true Orthetrum, and not a Nesoxenia. 



Long. corp. 43millim.; exp. al. 68 millim.; long. pter. 

 5 millim. 



Male. — Head yellow, frontal tubercle concave ; thorax 

 lighter or darker olive, with five dark reddish or black stripes 

 above, one on the central carina and two on each side, of 

 which the lower one is often hidden by the pruinosity which 

 covers the sides and under surface of the thorax in adult 

 examples, and partly extends to the legs, which are black, 

 striped below with testaceous ; abdomen pruinose blue ; anal 

 appendages as long as the ninth segment, lower appendage 

 two thirds as long as the upper ones. Wings with twelve to 

 fifteen antenodal cross-nervures, the last continuous, and nine 

 to ten postnodal cross-nervures ; pterostigma moderately long 

 and broad, yellow, between black nervures, the uppermost 

 thick, the apical half of the wings clouded with smoky yellow ; 

 nodal and subnodal nervures considerably waved; triangle of 

 moderate size, with one cross-nervure and a supra-triangular 

 nervure, followed by three rows of cells, increasing; supra- 

 triangular space consisting of three cells ; triangle of hind 

 wings not traversed. 



The female and immature male are yellow, with five reddish- 

 brown lines on the thorax, and the sutures of the abdomen 

 black, with a broad brown band running along each side; the 

 legs are also streaked with black, and the smoky yellow cloud 

 on the outer half of the wings is either much reduced or, in a 

 few cases, entirely obsolete. 



