TE +» DU li ik E 
Notes on Distribution and Ecology 
of North American Jasside, 
by HERBERT OSBORN. 
The Insects of this group have been the subject of considerable 
study, and we are now in position to give something of the limits 
of distribution for the different species, and a note in this connec- 
tion may be in place. 
Our Jassid fauna in North America is closely related to that of 
Europe, and while there are not such a very great proportion of the 
species, there are a number of instances where the species are either 
identical or so closely related that they must be considered as 
having had a very recent separation. 
In the most part for the Jassidee proper it appears that the rela- 
tion is mainly with the Holarctic fauna, and the direction of migra- 
tion has been either from the northeast, implying an invasion of 
the Palearctic species from that direction and the dispersal to the 
south or southwest, or as perhaps more distinctly indicated by 
certain species, an invasion from the northwest and a dispersal 
from that quarter. The latter is indicated by the occurrence of cer- 
tain of our species that are closely related to the Japanese or Sibe- 
rian fauna. In some of these species there is perhaps equal reason 
to believe that the direction of dispersal has been from America to 
the Palearctic region. There are some instances of very peculiar 
occurrence that need special note. One of the most striking of these 
is the case of Cicadula 6-notata, a species which is widely distri- 
buted in the Palearctic region, and is at present distributed 
throughout the entire Nearctic region. It is a very strange fact that 
no record of this species appears in the American records up to 
about the year 1880, and as this species is a conspicuous one and 
common upon a number of cultivated crops, the failure to record it 
seems to be of special significance. This is especially true since 
extended observations by such observers as SAY, HARRIS, FITCH, 
WaLsH and UHLER would seem to have made it almost certain 
that the species would be recognized if present. While it is hardly 
safe to conclude that the species is a recent introduction, especially 
