176 CERATOPHORUS. 



cence ; the mesothorax with three abbreviated longitudinal im- 

 pressed lines in front, and two deeper ones parallel with the 

 tegulae ; the thorax is rugose ; the metathorax with a semi- 

 circular space at its base, enclosed by an elevated ridge ; the 

 truncation with a deep fossulet in the centre, the whole of the 

 metathorax coarsely rugose ; wings fusco-hyaline and iridescent, 

 the nervures piceous, stigma black. Abdomen: the petiole 

 rugose, longer than the first segment, and curved; the apex 

 pubescent. 



Male. Differs in having the face clothed with silvery pubes- 

 cence, in having the mesothorax punctured, not rugose, and the 

 abdomen more elongate. 



Var. a. The limbus which encloses the semicircular space at 

 the base of the metathorax smooth and shining. 



I consider the variety of the male, which is Shuckard's P. luc- 

 tuosus, nothing more than a variety : on examining numerous 

 examples of that sex, intermediate approaches will be found; but 

 I have never seen a female with any tendency to the variety. 



This is one of the most abundant insects in the whole fossorial 

 group; it burrows in posts, rails, &c. in a decaying state. Its 

 cells are provisioned with different species of Aphides. I have 

 observed it settle on a rose-tree, and scraping a number of 

 Aphides into a ball, fly off with it, carrying it in front of its 

 anterior legs, and under its head. 



Genus 9. CEEATOPHORUS. 



Pemphredon, pt., Van d. Lind. Obs. ii. 82 (1829). 

 Ceratophorus, Shuck. Foss. Hym. 195 (1837). 



Head transverse, deeply excavated behind ; eyes lateral and 

 ovate ; stemmata in a triangle ; antennae inserted at the base of 

 the clypeus, not approximate ; the clypeus deeply emarginate, 

 the angles produced, subdentate; the labrum exposed, smooth, 

 shining, oblong, and rounded at the apex ; the mandibles biden- 

 tate ; an obtuse tubercle in the centre of the face, just above the 

 insertion of the antennae. Thorax ovate ; the anterior wings with 

 one marginal and two submarginal cells the first submarginal 

 cell oblong, receiving the first recurrent nervure beyond the 

 middle; the second submarginal much broader than long, receiving 

 the second recurrent nervure just within near its base, widest 



