20 MUTILLZ OF NEW HOLLAND. 
induced to add a figure of it, and of Diamma cerulea, to my 
representations of Australian Mutille. 
As the genus Psamatha has been described at some length in the 
work above referred to, it will be necessary only that I should 
notice some peculiarities omitted by Mr. Shuckard ; these relate 
especially to the structure of the mouth. The clypeus (plate 54, 
fig. 5 a) is carinated down the middle, beg produced in a trans- 
verse lobe over the labrum, of which the anterior ciliated margin 
is almost hidden. The mandibles are much curved, and terminate 
in three acute teeth, the apical one being the largest. In the male 
Mutille the mandibles are simply bifid; the same is also the case 
with the majority of the Thynni. The Chilian Telephoromyia Guér. 
and the Kangaroo Island Tachypterus Guér. have, however, the man- 
dibles bidentate within. The maxille (fig. 5 5)in Psamatha do not 
materially differ from the general form of these organs amongst the 
fossorial species, with 6-jointed maxillary palpi; the labium (fig. 5 c) 
in my specimen is considerably exserted and emarginate at the tip, 
arising from a very narrow carinated mentum, slender in front, and 
with 4-jointed labial palpi. The ungues in all the feet are bifid, 
(fig. 5 d), in which respect the insect agrees with the Thynni, and 
differs from the Mutille. The eyes are but very slightly emargi- 
nate on the inside, whereas they have a deep notch in the male 
Mutille. The veins of the wings extend quite to the apical margin 
as in the Thynni, whereas in the Mutille they stop at some distance 
from the margin. And lastly, the want of colour in these organs, 
as in this insect, occurs in the Thynni more ordinarily than in the 
Mutille. The extremity of the abdomen (fig. 5 e) is incorrectly 
described by Mr. Shuckard, as it has only one valve on each side 
projecting beyond it (in my specimen being coloured whitish) 
forming the quadrant of a circle, and externally fringed; the 
apical ventral plate is truncate at its extremity, and not produced 
into a spine as in many Thynni, nor bidentate as in the male 
Mutille. 
Species 1.—Psamatha chalybea, Shuckard. (Plate 64, fig. 5.) Chalybea nitida griseo- 
pubescens, margine postico prothoracis albido, abdomine atro utrinque maculis quatuor 
albidis, pedibus rufis basi nigris, tarsis piceis. Long. corp. lin. 6—63. Expans. alar, lin. 
114. f 
Habitat in Terra Van Diemenii. Mus. Soc. Ent. Lond. Saunders, Shuckard, et Westw. 
I am indebted to W. W. Saunders, Ksq., for this interesting 
species. 
