H. M. PARSHLEY 
9 
al)Sont ; color generally black. In this grouji the basal expansion 
of the corinin is reduced, so that in a majority of the American 
sjiecies the lateral margin of the corium is straight. 
Cinnamomeus ( Iroup. — Antennae short and thick, almost monil- 
iform; pronotal carinae vestigial; color reddish brown. single 
isolated species of wide distribution, which has some affinity, 
perhaps, with the subgenus Qinlnus, esi^ecially in type of pterygo- 
polymorphisni. 
Orbidilus (iroup. — Second antennal segment very slightly cla- 
vate and as long as head; extreme sexual dimorphism. A single 
species with small stenopterous male and lai'ge brachypterous 
female, somewhat related to Qvilnvs in wing characters and 
pi'onotal form. 
InsoUtus Ciroup. — Margins of pronotum strongly angulate; 
rostrum extending but little b.eyond base of head. The remark- 
al)le species constituting this group has little relationship with 
others, but forms a connecting link Ixdween the su])genera by 
I'eason of its very short rostrum. 
Subgenus Quilnus . — The three American species form a single 
well-defined group characterized ])y the short rostrum, not reach- 
ing the base of the head; pronotum small, without expanded 
margins; and a strong tendency to wing reduction. Kii'itshenko’s 
statement '‘marginibus lateralibus pronoti totis rectis” will not 
always api)ly, since in macropterous forms the sides may Ije 
distinctly sinuate (vide fig. GO). 
Distribution 
Species of the genus Awdus have been found in all the great 
faunal divisions of the world, but a vast majority inhabit the 
northern hemisphere, few occurring in the tropics. That this is 
a true expression of the facts, and not one founded merely on 
inadequate collecting, becomes clearly evident if we consider 
the records of Aradidae given by Champion in the Biologia Cen- 
trali-Ainericana (1897 to 1901). The Aradinae and Alezirinae 
(Brachyrhynchinae) are found in similar situations and collected 
by the same methods, but of Aradid, representing the former, 
only one species, /a/./c/H', is recorded, while of the various ATc'zirine 
genera seventy-six species are listed. In the mateiial which 
THANS. AM. EiXT. SCK'., XLVII. 
