CEECEEIS. 121 



length of the second and third antennal joints united, and from each other by less than 

 the length of the third joint. Clypeus subconvex, the sides projecting, especially at the 

 apex, straight, and continued as stout teeth beyond the apex. Antennal tubercle elongate, 

 sharply pointed, depressed at the base and apex; third antennal joint one quarter 

 longer than the fourth. Head coarsely punctured, large, well developed behind the eyes, 

 sparsely covered with long pale hair ; the oral region thickly clothed with silvery pubes- 

 cence. Thorax subopaque, clothed with short pubescence, strongly punctured ; meso- 

 sternum with a stout tooth projecting obliquely backwards, and there is a short tubercle 

 in front of it, and a blunt tooth at the apex. Median segment with a gradual rounded 

 slope, the heart-shaped area semiopaque, bearing a few large punctures laterally, and with 

 a shallow crenulated furrow in the centre. Petiole longer than broad, gradually bulging 

 out slightly in the middle, and clearly separated from the second segment. Contraction 

 at the apex of the second segment wide. Pygidial area elongate, narrow, of nearly 

 equal width at the base and apex, bearing large punctures, irregularly transversely 

 striolate, and covered with fuscous depressed pile ; the apex is rounded ; the sides bear 

 large punctures, and are fringed with stout pale projecting hairs ; beneath, the ventral 

 segment is carinate in the middle, incised at the apex, and projects into stout converging 

 teeth. The punctuation on the abdomen is strong ; the pubescence is sparse, except 

 on the apical segment. The base of the mandibles and the scape beneath are yellow ; 

 the flagellum beneath and the basal three joints of the antennae above are rufous. The 

 anterior and middle tibiae are obscure white in front ; the spines and metatarsus are 

 white; the spurs and claws are rufous. The second abdominal segment beneath is 

 for the greater part yellowish-white ; the sides and apex above, a narrow line on the 

 apex of the fourth, and an obscure line on the fifth segment are yellow. 



The flat, not rounded, centre of the clypeus, with the apex transverse and toothed (or 

 at least projecting), distinguishes this species from its allies; the toothed mesosternum 

 separates it from C. obsoleta, &c. 



Apparently not uncommon. 



23. Cerceris truncata. (Tab. VII. figg. 19, head, 19 a, clypeus, 19 b, pygi- 



dium, 19 c, hypopygium, $ ; 20, head, 20 a, pygidium, 20 b, hypopygium, 8 .) 



Clypei pars media libera, margine apicali truncato; oculomm margines fere divergences; area cordiformis 



aciculata ; macula clypeo, oculorum orbitis, maculis duabus scutello, metanoto, maculis tribus segmento 



mediali, abdominisque segmentis 1°, 2°et 4° margine apicali flavis ; alis fuscis, anticis fortiter fumatis. $ . 



Long. $ 11, S 8 millim. 



Sab. Mexico, Temax in North Yucatan (Gaumer). 



Eyes slightly diverging beneath. Hinder ocelli separated from the eyes by a little 

 more than the length of the third antennal joint, and from each other by the length of 

 the fourth. Head rugosely punctured, the face not quite so strongly as the vertex. 

 Clypeus free at the apex, not projecting very much, the apex truncated, the projecting 



biol. cente.-amee., Hymenopt., Vol. II., December 1890. ek 



t\ 



y o 



