128 Annals Entoniological Society of America [Vol.: VIII, 
to separate them. Both‘have-a venational peculiarity unknown 
in all other Myrmeleonide:- Another genus, Creagris, common 
-in Africa and India, even to Australia, 1s represented in South 
America by Dimarella,- which possesses the same structural 
peculiarities, otherwise unknown in the family. One of the most 
distinct genera of the Chrysopide is Apochrysa. It occurs in 
Australia, Insulinde, Ceylon, Africa and Eastern South America 
up into Central America. A distinct genus of caddice flies, 
Leptonema, common in South America, occurs elsewhere only in 
Africa and Ceylon. The Oestropsychid caddice flies, of which 
there are five genera, have a similar distribution, one genus in 
Insulinde, three both Indian and African, and one Brazilian. 
The restricted genus Embia, abundant in Africa, has several 
species in Brazil. The peculiar Oligoneurine mayflies are known 
from Southern Europe, Africa, Northern South America, Cen- 
tral America and West. Indies. These instances from the 
Neuropteroid insects can be duplicated in other orders of 
insects. What does this relation between South America and 
parts of Africa and India mean? 
Consider a third series of cases. Again and again entomol- 
ogists have called attention to the fact that. many structurally 
isolated Australian and New Zealand insects find their nearest 
counterpart in certain Chilian forms. This is as noticeable in 
the Neuropterotd insects -as’ in:other=orders.; he curious 
-Australian Perlid genus, Eusthenia, is closely related (as far as 
existant forms are concerned) only to the Chilian genus, Diam- 
phipnoa. Stenosmylus occurs only in Australia, New: Zealand, 
and Chili; Pszlochorema only in Chili and New Zealand; the 
Chilian Mantispid, Drepanicus, is most-closely related to the 
Australian genus, Ditaxis. The termite, Porotermes, 1s from 
Chili, Australia, Tasmania, and South-Africa. siete surely 
must be a reason for this distribution. ~ 
There are still other series of cases:of widely - discontinuots 
distribution. One is the similarity between-certain insects of 
Patagonia, the Straits, Falkland Islands,- etc.,-and: insects of 
‘Europe and North America. T he Limnephilid. caddice flies are 
almost. wholly Holarctic in distribution, and. constitute -a:large 
share of our Trichopterous fauna. - One .or two reach. North 
Africa and Mexico. .In the tropics ‘there are none, but,in this 
-Patagonian region they reappear in genera. the.sameor closely 
