very slender, and consisting of four joints, which is likewise the case with the labial pair; spines of the hinder legs pectinated on the inner side.
To exemplify this genus we have represented a new and splendid species from the collection of the Rev. F. W. Hope, which, on account of its large size and vivid colours, Mr. Westwood has named C. nobilis. It is of an intense black, clothed with very short velvet-like plush; the three terminal segments of the abdomen brick-red, and the wings black, with an exceedingly brilliant purple gloss; the length is about thirteen lines; expanse of the wings nearly two inches; the second submarginal cell receives the first recurrent nerve, and the second recurrent nerve is confluent with the nerve which closes the third submarginal cell; the hind legs are extremely hirsute, with two long and acute tibial calcaria, both denticulated, but one more strongly than the other; the upper lip is triangular; the mandibles with four teeth, the two inferior ones strongest and obtuse; the maxillary palpi short, very slender, and four-jointed.
Locality doubtful; but in all probability South America.
CENTRIS GROSSA.
Plate XX. Fig. 2.
Head bluish-black, with a mixture of green; antennæ black; thorax of a dark golden green, inclining to
