Hymenoptera aculeata collected in Algeria: the Sphegidae. 89 
1 9. Woods near Médéa, on (?) Daucus setifolius, 8. viii, 
93. A. E. E. 
1 g Bone (“border of estuary—near the railway 
works”). A. E. E. 
I think these are all arenaria, but the § and the Bone 
a seem to have wider and less emarginate yellow bands 
(esp. on segments 1 and 2) than normal European 
specimens. 
(I am not quite certain that Mr. Eaton’s record of 
Daucus as the plant visited by the ? refers to the insect to 
which I have attached it, but that is how I understand his 
note on the subject.) 
CERCERIS NITRARIAE, 0. sp. 
This is evidently one of those pale-yellowish species, 
very sparingly marked with black (chiefly on the vertex 
and mesonotum), and with somewhat silvery pilosity, 
which seem especially characteristic of the N. African 
desert-fauna. Unfortunately all the specimens before me 
seem to have had their original colour much altered by 
cyanide, and I have no means of ascertaining how far this 
circumstance is responsible for the varying combinations 
of different yellowish tints (cream-colour, fulvous orange, 
and even testaceous red) which their paler parts now 
exhibit. I think, however, that these parts were not even 
originally quite unicolorous—some being probably lacteous, 
and others distinctly lemon-yellow. Abandoning the 
attempt to distinguish these tints, the coloration of the 
insect may be described as “flavescens sparse nigro- 
maculata.” The vertex is crossed by a wide black fascia 
which is produced in front (biramose) so as to embrace the 
insertions of the antennae. The mesothorax, the pleurae 
at least in part, and the shining “‘cordiform area” are 
black, and some at least of the abdominal segments (all 
in the f) are more or less widely black at their bases. As 
in most species the f shows a greater extension of black 
not only on the abdomen but on the head and thorax than 
the 9, ¢.g. in the latter the tempora are yellow or fulvous, 
but in the ¢ they are black as well as the vertex and only 
bear a small spot of yellow behind each eye. In both 
sexes the collar, tegulae, and postscutellum seem to be 
always yellow. The scutellum may be yellow, or merely 
spotted with that colour (or with red ?), or entirely black. 
