482 HALIDAY ON 



this areolet becomes very minute. Of tlie lower wings, also, 

 the nervures are disposed after a peculiar type, to which, 

 among the proper IcJmeiiniones, Porizon and some of the 

 Cremasti make an approach ; a few have two radial areolets, 

 some also two cubital, and, in one extensive group, the com- 

 mencement of a complete discoidal areolet beyond the second 

 brachial is traced by a recurrent nervure. 



Their habits, so far as ascertained, present no broad distinc- 

 tion from the rest of the family. I am not aware that any of 

 them are hyperparasitic ; but in their earlier states they are 

 themselves obnoxious to the attacks of certain of the proper 

 Ichneumones, of the Chalcides, and the Oxyuri. For their 

 transformation, the majority enclose themselves in a silky 

 cocoon; this is dispensed with in a' few instances, where 

 the nature of their nidus renders such a protection unneces- 

 sary. 



Tabula SynopHca. 



isub pectus incurvatile Apihdini. 

 /'contigiia conipleta • Sigalphini. 

 baud incurva-1 ^^^^j.^ s.incompleta:['nervum unicum Braconii. 

 tile : Areolai^ irachialis posterior a-) 

 disci anhca I, ,/ ., { 

 I larumposttcarumemit-\ 



\tevs ' iiervos binos .' Agathenses. 



Trihus 1. — Aphidini. Haliday. 

 Comjjlectitur genus unicum. 



Gen. I. — Aphidius. Essenbeck. 

 Incubus. Schrank. 

 Hybrizon. Fallen. 



Thorax brevis gibbus : abdomen sub pectus incurvatile : 

 aculeus breviter exertus, compressus : valvtda ventralis 

 carinata amnn siqierans. 



Caput postice contractum : vertex late rotundatus : occiput angus- 

 tum truncatum undique marginatum : mandibulas forcipatoe, 

 cuneatae, parum curvatae, apice emarginatas s. acute bidentes : 

 labrum subtrigonum apice appendiculatum : palpi varii maxil- 

 lares ad summum 4-articulati : caput et abdomen thoraci annexa 

 solito inferius : thorax brevis antice gibbus : alae superiores areola 

 disci antica vel subcontigua, vel sa^pius incompleta : inferiores 

 nervis longitudinalibus binis tantum, areolam brachialem sajpius 



