612 Mr. F. D. Morice on new Hymenoptera. 
it at a glance from any European species. The actual hairs 
seem, however, to be pure white, and it is only where they 
are prostrate that the blue effect appears. I imagine that the 
underlying or surrounding subcyaneous chitin is either seen 
through them or reflected by them in some way (the tint is 
just that produced by a thin layer of Chinese white over a 
wash of black or dark blue paint). 
The almost complete absence of reliable structural characters, 
even in the males, makes the proposal of new Crocisa species 
risky and unsatisfactory ; but as I can find no description 
which at all suits the present insects, and as Herr Friese, to 
whom I sent the specimens, returns them as unknown to him, 
I have ventured to describe them as new. 
The bluish-white hair-patches on the scutellum ttself are a 
very peculiar character, this part in Croczsa being otherwise, 
so far as I know, always immaculate. They are very large 
and subquadrate in the male, smaller and rounder in the 
female. The other pilose ornaments of the thorax and also 
those of the abdomen are arranged exactly as in ramosa, 
differing only in looking bluish, as described above. On the 
legs they are not blue, and (by contrast, I suppose) look even 
a little yellowish. 
Rhynchium Sirdart, sp.n. ¢. 
Colore omnino ut synagroides, sed structura alia. Clypeus 
semicirculariter emarginatus, angulis apicalibus spiniformibus, 
longitudine sua evidenter latior. Mandibule valide, late, minus 
quam in synagroide elongate; margine apicali dentibus 2 in 
medio instructo, contiguis quidem sed bene distinctis, quorum 
exterior interiore duplo longius. Postscutellum, a latere visum, 
acute conicum: area huius basalis vel horizontalis brevis, crasse 
punctata, et in medio carina alta longitudinali, vel dente com- 
presso, armata. Abdominis segmenti secundi pars ventralis, ut in 
synagroide, basi subbituberculata; sed disco leeviore, punctis 
sparsis, magnis quidem sed minime profundis. 
Long. cire. 26 mill. 
Khartum, 31 1. ’01. 
The semicircularly emarginate clypeus, with its long spine- 
like angles, at once distinguishes this species from ardens g 
as described by Saussure, and also from specimens called 
abyssinicum g in the South Kensington Museum, which 
(like abyssinicum 2) have a subtruncate clypeus. From 
synagroides g it differs in having the clypeus evidently 
wider than long, the mandibles stouter, and the teeth on their 
apical margin better developed. Also in synagrotdes the 
ventral surface of the second abdominal segment is far more 
