TEMTHREDIXID.*:. SELANDUIA. 45 



diminishing in length and thickness to the apex, the terminal joint being 

 short, and somewhat conic : mandibles bidentate : labrum emarginate : head 

 broad : ocelli 3 : wings ample, anterior thin, with 2 marginal areolets, 

 divided by a straight nervure, placed a little obliquely, and 4 submarginal 

 ones, the 1st small rounded, 2nd and 3rd of equal size, the former receiving 

 1 and the latter 2 recurrent nervures, the 4th larger, extending to the apex 

 of the wing: body broad, scarcely longer than the thorax, somewhat depressed 

 and ovate in the females : legs simple, with a pair of short unequal spurs at 

 the apex of the tibiae alone. 



Although in the structure of the wings there is great similarity 

 between the insects of this genus and in those of AUantus and 

 Tenthredo, nevertheless the brevity and stoutness of the antennze, 

 the shortness and ovate depressed bodies, the comparatively greater 

 amplitude of the wings, in which the marginal areolet is generally 

 divided by a straight nervure, will sufficiently distinguish them from 

 those genera, as will the areolets of the wings* from those contained 

 in the present section : the species are generally small, and of dark 

 and sombre colours, some of the early ones, however, simulating the 

 Athali^. 



Sp. 1. serva. Flava, antennis, capite thoracisque dorso sternoque nigins, alis 

 hyalinis, basi costaque dimidiata Jlavis, stigmate nigra. (Long. corp. 

 24— 5^ lin.; Exp. Alar. 54—12 iin.) 



By. serva. Fabricius. — Se. serva. Steph. Catal. 330. No. 3830. 



Head and antennae black ; palpi testaceous; thorax yellow or luteous, with 

 its disc above and the sternum shining-black ; abdomen and legs immaculate 

 yellow, the last palest; wings hyaline, with the base and half the costa 

 yellow, nervures the same, the apex of the latter fuscous, stigma black. 

 Not uncommon in marshy situations within the metropolitan 



district, in June and the beginning of July. 



Sp. 2. dorsalis. Luteo-Jlava, anticis capite thorace supra infraque abdominisque 

 segmentorum omnium basi supra nigris, stigmate fusco. (Long. corp. 4 — 

 54 lin.; Exp. Alar. 8—10 lin.) 



Se. dorsalis. Steph. Catal. 330. No. 3831. 



Head and antennae black ; thorax black above and beneath, the shoulders 

 sometimes lutescent ; abdomen luteous-yellow, with its basal segment 

 almost entirely and the other segments at the base black ; legs pale luteous- 



* As before alluded to, the variations of these must not invalidate the rule ; 

 I possess an example of Se. serva with 2 marginal and 5 submarginal areolets, 

 and a Nematus vicinus with 1 marginal and only 2 submarginal areolets. 



