ustry of their larvae. The first are workers in mosaic, encrusting a
network of silk and sand; the second weave pure silk.

Of smaller size and clad in black with trimmings of silvery down on the
edge of the abdominal segments, the Tarsal Tachytes frequents the
ledges of soft limestone in fairly populous colonies. (T. tarsina, LEP.)
(According to M. J. Perez, to whom I submitted the Wasp of which I am
about to speak, this Tachytes might well be a new species, if it is not
Lepelletier's T. tarsina or its equivalent, Panzer's T. unicolor. Any
one wishing to clear up this point will always recognize the quarrelsome
insect by its behaviour. A minute description seems useless to me in the
type of investigation which I am pursuing.--Author's Note.) August and
September are the season of her labours. Her burrows, very close to
one another when an easily-worked vein presents itself, afford an ample
harvest of cocoons once the site is discovered. In a certain gravel-pit
in the neighbourhood, with vertical walls visited by the sun, I have
been able within a short space of time to collect enough to fill the
hollow of my hand completely. They differ from the cocoons of the
preceding species only in their smaller size. The provisions consist of
young Acridians, varying from about a quarter to half an inch in length.
The adult insect does not appear in the assorted bags of game, being
no doubt too tough for the feeble grub. All the carcases consist of
Locust-larvae, whose budding wings leave the back uncovered and put one
in mind of the short skirts of a skimpy jacket. Small so that it may be
tender, the game is numerous so that it may suffice all needs. I
count from two to four carcases to a cell. When the time comes we will
discover the reason for these differences in the rations served.

The Mantis-killing Tachytes wears a red scarf, like her kinswoman,
Panzer's Tachytes. (The Mantis-hunting Tachytes was submitted to
examination by M. J. Perez, who failed to recognize her. This species
may well be new to our fauna. I confine myself to calling her the
Mantis-killing Tachytes and leave to the specialists the task of
adorning her with a Latin name, if it be really the fact that the Wasp
is not yet catalogued. I will be brief in my delineation. To my thinking
the best description is this: mantis-hunter. With this information it
is impossible to mistake the insect, in my district of course. I may add
that it is black, with the first tw