Odonata from New Caledonia. 45 



failed to notice the difference in tlie form of tlie posterior 

 lobe of the prothorax, which is more quadrangular in e.csudans 

 tlian in the other insect. But for tliis and the wholly 

 different anal appendages, it would be difficult to distinguish 

 our specimens of exsudans from material o£ the so-called 

 jiygmrsa from Seychelles with which I have confronted them *. 

 The resemblance between the two species, which is at all 

 times very close, is accentuated by the present comparison, 

 for all four males of exsudans are free fiom the pruinosity 

 on head, thorax, and femora which characterises the type- 

 specimen, and one of the two which retain the last three 

 segments of the abdomen have them coloured reddish brown, 

 as ill pijgiiicea. 



Family Libellulidse. 



Subfamily Corbvliinm. 



Hemicordulia oceaiiica, Selys. 



' 1 c^ , Plaine des Lacs, 18. ii. 14 (264). 



This species was originally described fi'Oin Tahiti, and the 

 British Museum possesses a male collected in that island 

 during the visit of H.M.S. ' Challenger ' in 1875. The fact, 

 however, was not mentioned in Kirby's paper on tiie 

 Neuroptera of the * Challenger ' Expedition (Ann. & Mag, 

 Nat. Hist. (5) xiii. pp. 453-6, 1884). 



1 ? , Bale Ngo, 25. iv. 14. 



Martin refers to a " ? incomplete^' in the De Selys 

 Collection (Coll. Selys, Cord. p. 12, 1906), but the only 

 description of that sex which seems to be available is that 

 given by His of an individual from New Britain doubtfully 

 referred to H. uceanica (Nova Guinea, ix., Zool. p. 503, 1913). 

 As our specimen from New Caledonia is in good condition, 

 and is doubtless to be associated with the male in the same 

 collection, a brief account of it is subjoined. 



Length of abdomen 37 mm. ; hind wing 34*5 mm. ; 

 pterostima 2 mm. 



Labium yellow ; labrum yellow to bi'ownish yellow ; 

 clypeus greenish yellow ; frons hairy, orange anteriorly, 

 metallic green above. Vertex orange, partially overlaid with 

 metallic green. Occipital triangle orange, very hairy. 

 Antennse black. 



* Males of this species from Seychelles do not seem to show any 

 essential points of ditterence from males of ^. Iiyacintlms, Tillyard, from 

 Queensland, which Dr. Tillyard has been kind enough to send ms. 



