1052 The American Naturalist. [December, 
manner of Peripatus. Thus, Palwococcus, to which the fossil species 
are assigned, has three living species, one in Europe, one in South 
America and one in New Zealand. 
Ortonia has also three species; one from Natal, the other two neo- 
tropical. 
Icerya appears to be neotropical, Oriental and Australian; and 
there is an allied genus or subgenus, which I hope Prof. Riley will 
soon describe, found here in New Mexico. 
Porphyrophora is considered Palearctic, but has its representative 
in America in Margarodes, with one West Indian and one Chilian spe- 
cies. Cclostoma is confined to Australia and New Zealand, and thus 
forms an exception among the polytypie monophlebid genera; but 
Monophlebus is recorded from widely separated countries in the East- 
ern Hemisphere. 
Gossyparia has five species, two Palzearctic, two Australian and one 
from New Zealand—truly a curious distribution ! 
Eriococcus is interesting. Six species are Palearctic; Australia 
and New Zealand together have no less than sixteen, only one of which 
is common to both these countries, and then the Australian form is a 
distinct variety of a New Zealand species. No other species whatever 
are known except three from North America, two of which, E. azalee 
and E. coccineus, cannot well be native there. In the West Indies, 
where Dactylopius abounds, no Eriococcus has been ever seen. 
Rhizococeus presents one Palæarctic species, three from Australia and 
six from New Zealand. We seem to have in this country two unde- 
scribed species, however. 
Bergrothia, which is very near to Dactylopius, has one Palæarctic 
cies ; while two very nearly allied forms are found in New Mexico, 
and referred by me to the same genus. Still another is reported from 
Indiana, etc., but is undescribed. 
Daetylopius seems to be rich in species in most parts of the world, 
but becomes rare and is supplanted by Phenacoccus in the northern 
parts of the Palearctic region, such as England. The neotropical 
species are numerous, but the nearctic forms are singularly few, and 
(excepting introduced ones) all western. Mr. Coquillett has described 
them, and I have sent the description of a fourth to the printer, 
There are nine known species from Australia and eight from New 
Zealand ; for the most part these differ in type from the neotropical 
forms, so that it might be proposed to place them in a distinct subge- 
nus. The genus Dactylopius, as now understood, contains very diver- 
gent forms, but great difficulty is felt in any attempt to separate it into 
 subgeneric groups. 
