230 HALIDAY ON 



to the entire of each group; and as Von Essenbeck has long 

 since shown the affinity which subsists between Chelonus 

 among the Bassi and Microgaster in the present family, I 

 commence the latter with that genus. Here, however, seems 

 to be the most convenient place to introduce a genus anomalous 

 in its palpi, but bearing, on the whole, more resemblance to 

 Microgaster than to any others of the family, although the 

 differences are sufficient to prevent my comprehending them 

 under one generic name, and even to leave their affinity open 

 in some degree to doubt. This may be owing, partly, to the 

 want of sufficient materials, the genus being founded on the 

 examination of a single ill-preserved specimen. 



Gen. II. — MiRAx. 



Palpi maxillares 4<-articulati, labiates 3-articulati : antenncc 

 \^-articulatcJB : occiput retusmn : oculi glabri : meso- 

 thoracis scutum haud tripartitum : abdomen breve sub- 

 sessile : aculeus subexertus. 



Sp. M. rufilabris. Fern. Niger, piedibus Jlavo-ferrugineis : 

 alee hyalince: os, clypeus, squamulcB et stigma ferruginea : 

 abdominis segmenta 2 anteriora flava. (Long. corp. .08. 

 alar. .2.) 



Caput thoracis latitudine, transversum crassum ; occiput retusum ; 

 vertex late rotundatus ; ocelli in triangulum ; oculi parvi glabri :^ 

 antennae corpora parum breviores, graciles, 14-articulatae ; scapo 

 ovato-cylindrico, pedicello extricato ovato, articulo tertio longiore 

 quam scapo, reliquis longitudine decrescentibus : labrum trans- 

 versum lateribusrotundatum, epipharynga obtegens, hujus tantum 

 ligul^ apicali attenuata prostante ; mandibulae trigonse apice 

 curvatae et tenue bidentes ; maxillae lobus latus obtusus ; labium 

 integrum obtusum ; palpi maxillares 4-articulati, articulis l'"". 

 breviore, l^"^. paulo crassiore ; labiales 3-articulati : thorax ovatus 

 (•epressus ; pro thorax inconspicuus ; meso thoracis scutum rotun- 

 datum, planiusculum, sulculis ordinariis omnino nullis ; metathorax 

 rotundatus : alse anticae — stigma crassum rotundato-trigonum ; 



' This character has had some weight in inducing me to separate the genus 

 from Mirrogasfer ; it should be remembered, however, that the eyes are hairy in 

 one section of the genus Chelonus {Ch. sulcatus, &c.), while they are naked in 

 the rest. 



