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Genus ORNITHOPTERA. 



The present generic group was first separated from 

 Papilio by Dr. Boisduval. None of its characters, 

 taken singly, are very strongly marked, but their 

 aggregate importance is sufficiently considerable to 

 authorise its adoption. As in Papilio the antennas 

 form an elongate club, having the extremity slightly 

 curved upwards, the palpi are longer than in the 

 genus just named, but they never rise above the 

 forehead. The prothorax is much developed an- 

 teriorly, and forms a pretty distinct neck. The 

 abdomen is long and robust, that of the male deeply 

 grooved on the under side, and provided at the anal 

 extremity with two large rounded valves. The 

 wings are large, of a strong texture, and furnished 

 with salient nervures ; the anterior pair elongate ; 

 the posterior with wide shallow indentations, and 

 never prolonged into a tail. 



We are very imperfectly acquainted with the 

 natural history of the insects of this group in their 

 early stages. Their remote localities, and the rarity 

 of most of the species, have, for the most part, 

 prevented them from falling under the notice of 

 competent observers. The caterpillar and meta- 

 morphoses of one of them (O. Heliacon), however, 

 have been described by Dr. Horsfield. Like the 



