GENERAL CHAKACTERS. 5 



During flight, the anterior and posterior wings are connected by 

 means of a series of minute hooks, or spinulje (fig. 5, m), along the 

 anterior margin of the posterior i)air, which catch the hinder margin 

 of the anterior pair and thus produce one continuous surface on each 

 side. Occasionally the wings are more or less abbreviated, or entirely 

 wanting r apterous forms are found in the families Ichneumonidaj, 

 Braconidse, Cynipidae, Chalcidida?, Proctotrupidae, Formicidse, and 

 MutillidjB. 



Fig. 4. — Anterior wing of MelUnus. 



I, costal cell ; a, median or externo-medial cell ; 3, submedian or interno-medial cell ; 

 4, anal cell ; 5, marginal or radial cell : 6, first submarginal or cubital cell ; 7, second sub- 

 marginal or cubital cell ; 8, third submarginal or cubital cell ; 9, fourth submarginal or 

 cubital cell; 10, first discoidal cell; 11, second discoidal cell; I3, third discoidal cell; 13, 

 first apical cell ; 14, second apical cell : a, costal nervure ; b, subcostal nervure ; c, externo- 

 medial nervure ; d, anal nervure ; e, marginal or radial nervure ; f, basal nervure ; g, first 

 transverse-cubital nervure ; h, second transverso-cubital nervure ; i, third transverso- 

 cubital nervure; j, transverso-medial nervure; k, discoidal nervure; 1, cubital nervure ; 

 m, first recurrent nervure ; n, second recurrent nervure ; o, subdiscoidal nervure ; p, 

 stigma; q, posterior margin ; r, apical margin. 



Fig. 5. — Po.sterior wing. 



1, costal cell ; a, median cell ; 3, submedian ceil ; 4, anal cell ; 5, marginal or radial cell ; 

 6, submarginal or cubital cell ; 7, discoidal cell ; a, costal nervure ; b, subcostal nervure ; 

 c, externo-medial nervure: d, anal nervure; e, marginal or radial nervure; f, cubital 

 nervure ; g, discoidal nervure ; h, transverso-medial nervure ; i, transverso-cubital ner- 

 vure ; j, stigmal region ; k, basal lobe ; 1, sinus ; m, spinulae. 



