CBRCEKIS. 307 



. . . scutellum sparsely puuetnred, trigonal area smooth, impunc- 

 tate, farrowed down the middle . . . Petiole wider than long, 

 bulging out in the centre, sparsely and finely punctured, the fifth 

 segment also sparsely punctured, the others with the surface 

 aciculate. . . . Hinder tibise very stoutly and closely spiued. The 

 male has the face from the top of the antennal ridge entirely 

 yellow ; the clypeus flattish, the apex rounded, almost transverse, 

 the lateral plates incised, there is a small yellow mark below the 

 tubercles, theie are two large yellow marks on the median segment ; 

 the 4th segment is almost entirely yellow, the 5th has a narrow 

 yellow border on the apex, the Gth is almost entirely yellow, the 

 sides of the apical segment are yellow ; the legs are clear yellow ; 

 the hinder femora are marked with black, the hind tibia) are 

 broadly black at the apex, and the hind tarsi are fuscous ; other- 

 wise coloured as in the 2 • • • Length 11 mm." 

 Hah. Bombay. I have not seen this species. 



549. Cerceris instahilis, !^mHh, Cat. iv,p. 452,2; Schlett. Zool.Jahrb, 

 1887, p. 494 ; Cam. Mem. Manch. L. Ph. Soc. (4) iii, 1890, p. 249. 

 Cerceris velox, Smith, Tr. Ent. Soc. 1875, p. 41, cj' . 



2 (S . Head, thorax, and abdomen closely punctured ; clypeus 



broad, incised in the middle, with two prominent but obtuse teeth ; 



median segment with the enclosed triangular space at base 



equilateral, longitudinally striate in the 2 i punctured in the d , 



basal abdominal segment particularly slender and long. Reddish 



brown ; the region of the ocelli, with a broad patch below stretching 



laterally to the eyes and downwards to the base of the antennae, 



the pronotum in front, the triangular enclosed 



space at the base of the median segment, 



a medial narrow line down to the apex of 



the latter, and the bases of abdominal segments 



2-5 narrowly, black ; the clypeus, fnce in front, 



antennae, and legs more or less fulvous ; the 



posterior margin of the pronotum, the scutellum 



and postscutellum, a curled comma-shaped spot 



i^ig. SQ.~Cerceris on each side of the apex of the median segment, 



uisfabilis, 2- ?• a subbasal spot on the 2nd abdominal segment 



above, and the posterior margins of the 3rd and 



5th segments broadly, yellow ; wings hyaline, their apical margins 



broadly fuscous. 



Var. a. The front above the antenna;, the vertex and occiput 

 black, the last with a curved brownish-red transverse stripe. 



Var. /3. Similar to Var. a, but with no yellow spots on the 

 median segment ; the clypeus and face below the antennae, and 

 scape of the latter bright yellow. 



Var. y. The head and thorax black, with the yellow markings 

 as in the type. 



Var. d. Very much larger; head and thorax black; yellow 

 markings as iu the type, with the addition of a broad curved 



I 2 



