1863.] 
what squarely indented in the middle and with a very small black dot 
on each side; abdomen beneath with a dot on each side and a trans¬ 
verse spot in the middle of the second segment, and an uneven trans¬ 
verse band on the third, fourth and fifth segments, yellow, that on the 
fifth segment is narrower, divided in the middle with black, and with 
the yellow extending posteriorly on each side of the segment. 
Hah. Pike’s Peak. Collected by Mr. Winslow J. Howard. 
One male and two female specimens in the collection of the Entomo¬ 
logical Society of Philadelphia. 
The male of this species difiers remarkably in several points of struc¬ 
ture from the type of the genus, M. vespiformis^ as delineated by 
Messrs. Saussure and Schaum. It differs as follows:—The knob of 
the antennae is much broader, and more of an oval. The neuration of 
the superior wings is diflerent from that given by Dr. Schaum.* The 
marginal cell is not so long, the first submarginal more elongate, the 
second submarginal without any projection towards the marginal, the 
second discoidal cell much longer, the third discoidal not so square, 
but more elongate and bent towards the second submarginal. The 
figure given by M. Saussuref represents the neuration of the wing of 
our species much better, although the third discoidal cell is also too 
square. The singular structure of the anterior and in particular the 
intermediate tibim, and the posterior tarsi; the bifid styloid spine at 
the tip of the posterior tibim, and the simple tarsal claws J are charac¬ 
ters not noticed in M. vespiformis. The tip of the apical segment of 
the abdomen above, instead of being bifid, as seems to be the case in 
M. vespiformis^ is deeply and broadly emarginate, and the carinm and 
tubercles on its disk are very conspicuous. The projections on the 
second and third ventral segments are also diflerently constructed from 
those of M. vespiformis.^ that on the second segment being less devel¬ 
oped and bifid, while that on the third segment is strongly developed, 
bifid, and bearing an acute spine posteriorly. 
* Ann. Soc. Ent. Fr. 3 ser. 1, pi. 20. 
f Monog. des Masariens, pi. 5, f, 4. 
i I am satisfied that the tarsal claws in this species are simple, and that the 
styloid spine at the tip of the middle tibiae is deeply bifid, as I have examined 
them repeatedly with a strong magnifying power, and am quite convinced that 
it is the effect of no optical error, as suggested by M. Saussure (1. c. p. 17). 
