10 
AMERICAN SPECIES OF AKADUS (iIEMIPTERa) 
has been availalilc (lurino; the present study, I have come across 
four species from the regions south of the United States. Stab 
records gracilicornis from (hil)a, and Lethierry and SeveriiP indi- 
(*ate for angudellus a wide dispersal over the South American 
continent. Bergroth (1895) reports crenahis from Mexico, and 
Uliler (1878) mentions a specimen of qimdrilvmatus which he 
has from Panama. Champion'' remarks that there may lie some 
mistake regarding the two records last noted, lait the latter, 
at least, may be accepted. I have examined the specimen, still 
jireserved in the United States National Museum, which is a 
lierfectly typical (juddrilineatns (male) and bears the written 
label, “Pan.” In the C’ornell collection there are examples of 
7mjer liearing the label “Mex.” It is rcasonalily certain, how- 
ever, that further collecting on the central plateau of Mexico 
will result in the addition of a few more species to the fauna of 
Uentral America, since the genus is fairly well represented in the 
states which include the northern extension of this faunal area. 
In contrast to this paucity of representation in the Neotropical 
realm, we find about one hundred and thirty-five species occur- 
ring in the northern hemisphere, divided with approximate equal- 
ity between the Nearctic and Palaearctic regions. With the 
exception of a few to be noticed presently, the Old World forms 
are specifically distinct from those of the New, but many of them 
are closely related and there is every evidence of former inter- 
communication. Of the three Holarctic species, crenatus, Ingvhris, 
and cinnamomcufi, the first is confined on this continent to the 
('astern region (and Mexico ?); the third in its typical form occurs 
east ol the Rocky Mountains and south of C^anada, but has ])ro- 
duc('d a western race which range's as far nortli as British Colum- 
bia; while lugubris is met witli over the entire continent from 
lJi(i Mc^xican boundary to Labrador and Alaska. The distribution 
of this species atiords some evidence for the theory of jireglacial 
migration by tlu' northwest route, and might perhaps be cited 
as k'liding sonu' supjiort to Scharff’s''’’ criticism of the commonly 
a(‘C('pt('d vi('ws on the rigors of tlu' Ph'istoci'iie (*limale in the 
Imiuiii. llciii. 
^ ( ';il . ( <6ii. I It'iM. 
lliol. ( p. Ci.l, loot note. 
‘ 111 12, pp. 7(), rt .s'Cf/. 
