1864.] 
373 
black spots on the outer margin of the secondaries; two, connected, at 
one-third the length of the margin from the anal angle, the other, mid¬ 
way between them and the outer angle. Abdomen without spots. Be¬ 
low, immaculate, costa of primaries rosy. Length of body 3| lines ; 
of the wings 104 lines. 
Philadelphia. 
Should these prove to be new, I would propose for them the name 
of fri-maculosa. 
On the North American species of several genera of APID.ffi. 
BY E. T. CRESSON. 
Gen. ANTHIDIUM, Fabr. 
The characters of this genus are laid down by Mr. Smith {Bees e)f 
Great Bjataiii, p. 184) as follows;*— 
‘^The body usually adorned with yellow si‘)ots or stripes. Head nearly as 
wide as the thorax; the ocelli placed in a triangle forward on the vertex; the 
antennoe filiform, the basal joint of the flagellum obconical. The mentum linear, 
elongate and pointed at its apex; the labium elongate, blunt at its apex and 
channeled down the middle, one-third longer than the palpi; the latter four- 
jointed, the first and second joints elongate, gradually narrowed from the base 
to the apex; the two apical joints minute, placed at the side and near the apex 
of the second joint. The maxillary palpi consisting of one joint, placed on a 
cup-shaped basal tubercle (or joint?); the apical lobe of the maxilloe sickle¬ 
shaped. The superior wings having one marginal and two submarginal cells, 
the second submarginal cell receiving the first recurrent nervure a little within 
at the base, the second recurrent nervure uniting with the second transverse 
nervure. Abdomen incurved, furnished with a dense pollen-brush beneath in 
the femalesthe males having the aj^ex armed with spines.” 
Our species of this beautiful genus are apparently quite rare and 
may be classed as follows:— 
Sect. 1, containing those species which are large, broad and sub¬ 
parallel, having somewhat the form of a Megachile^ the body more or 
less hairy and subopaque, the wings hyaline, the second recurrent ner¬ 
vure uniting with the second transverse nervure, the abdominal seg- 
In giving the characters of the genera of Apidse, I copy the excellent de¬ 
scriptions of Mr. Frederick Smith, as given in his Catalogues of Hymenoptera 
in the British Museum, and think it unnecessary to draw up other descripti(ms 
when those of Mr. Smith are full and explicit. These descrijjtions are here 
given as an assistance to those not having tJie original ones convenient 
