STJB'FAMILY XYELINA. 109 



clypeus is yellow, the base of pronotum, tegulse, scutellum and post- 

 scutellum, yellow. 

 Long, 5J lines. 



Rare. New Galloway, Combe Wood and Hertford 

 (Stephens, 1. c.). 



Sub-family XYELINA. 



Antennae 9- to 12-jointed, the third much longer and thicker 

 than any of the others. Wings with three radial and four cubital 

 cellules. Transverse nervure received in first cubital cellule. Posterior 

 wings with two or three middle cellules. Two posterior tibiae spined. 

 Ovipositor longer than half the length of the abdomen. Prothorax 

 transverse. Middle lobe of mesonotum short, triangular, widely sepa- 

 rated from scutellum. Larva without ventral legs. 



As already remarked (p. 84) the affinities of this 

 sub-family are clearly with Pamphilius, as is shown by 

 the not dissimilar arrangement of the cubital nervures, 

 by the structure of the thorax, the spined tibiae, &c., but 

 the very remarkable antennae and palpi, the extra radial 

 cellule and the long ovipositor sufficiently differen- 

 tiate it from all the other sub-families of Tenthredinidce. 

 The curious genus Blasticotoma, Klug, has certain 

 affinities with it, and like it has the third joint of the 

 antennae very large and thick ; but there are only 

 four joints in all ; there are no spines on the tibiae, and 

 there are only two radial and three cubital cellules. 



Only two genera of Xyelina have been described 

 Xyela and Macroxyela the former with twelve-jointed 

 antennae and two middle cellules in hind wings, the 

 latter with only nine joints in the antennae and three 

 middle cellules in the hind wings. Xyela contains at 

 present only six European and one North American 

 species. Macroxyela is exclusively American. 



