1863.] 
281 
superior wing, while on the right wing the third suhmarginal cell is 
petiolated, i. e. the transverse cubital nervure that separates the second 
and third submarginal is suddenly angulated at its anterior third and 
becomes confluent with the third transverse cubital nervure before it 
reaches the radial nervure ; an example of this monstrosity is shown 
in the normal second submarginal cell of Miscophus ,—a genus of Lar- 
ridae. (See St. Farg. Hijmenopt. pi. 27, fig. 6 bis.) Mr. Walsh of 
E,ock Island, Ill., informs me that he possesses a % Nomada “ with the 
three normal submarginal cells on the left wing and only two on the 
right wing, the two next the base being confluent; and another S with 
two submarginal cells on the left wing and only one on the right wing.” 
The abdomen is short and ovate, but the segments are generally more 
or less distended and consequently vary in shape j the base of the first 
segment above has a more or less deep longitudinal excavation; the 
apical segment of the male is narrow, its lateral margins somewhat re¬ 
flexed and the tip mostly bifid, rarely rounded. 
As most of the species of this genus are liable to vary more or less 
in the color and markings, it will be found very difficult to separate the 
varieties and to tell correctly to what species they belong, without 
having a large series of specimens; but with a limited collection and 
with no intermediate grades of variation, it is hardly possible to avoid 
creating a number of species, which, after a large series of specimens 
has been accumulated, may prove to be only varieties. This, however, 
is generally the case with almost every variable genus of insects when 
first monographed, where synonyms are unavoidably created. 
The following have the appearance of being distinct species:— 
1. N. superba n. sp. 
Male .—Head large; black; densely, somewhat deeply and conflu- 
ently punctured, the punctures more sparse and less deep on the face; 
thinly clothed with whitish hairs; sides of the face, orbits of the eyes 
beneath, clypeus, labrum, a quadrate spot above the clypeus, mandibles, 
except tips, lemon-yellow. Antennas, when extended back, attains the 
scutellum; fulvous, apical joint paler, scape in front yellow, behind 
black. Thorax black, densely, somewhat deeply and confluently punc¬ 
tured ; collar, tubercles, tegulge, except a dot on the middle, a trian¬ 
gular spot on the pleura, immediately behind the fore feet, and two 
spots on the scutellum which is bilobate, lemon-yellow; thinly clothed 
I 
