130 ORIGIN, ETC., OF THE FAUNA. 
Mr. Cambridge finished his account of the Spiders. So, too, has the genus Psalmopeus, 
which contains the Costa Rican species reduncus and others from Ecuador, Colombia, 
and Trinidad. | : 
The genera Spherobothria from Costa Rica, Sericopelma from Panama, and 
Schizopelma from Mexico and Costa Rica have not, so far, been discovered beyond 
the limits of Central America, but, like the others cited above, and the remainder 
recorded by Mr. Cambridge, they are related to South American or West Indian 
genera of this great family, and with one or two exceptions have no near kinship with 
the genera characteristic of tropical Africa, Asia, and Australia, which belong to distinct 
groups or subfamilies, Two apparent exceptions to this, however, must be mentioned. 
The South American genus Avicularia which extends into Panama belongs to a group 
to which also belongs the tropical West African genera Scodra and [Heteroscodra ; and 
the genus Hemirrhagus, represented by one species, cervinus, in Mexico, seems to have 
its nearest ally in Cratorrhagus of the Mediterranean area. 
The conclusion suggested by the above-stated facts is this :— 
The Central American Mygalomorphe belong to two categories: (1) Those referable 
to groups which are in the main northern in distribution ; (2) those referable to groups 
which are in the main southern in distribution. 
1. To the northern group belong Pachylomerus, which occurs elsewhere in the 
West Indies, North America, Japan, and Spain; Chorizops, whose only known allies 
are found in North America and China; Bothriocyrtum, which occurs also in North 
America and is related to genera from Japan, China, Central Asia, and the Mediter- 
ranean area; Hnrico, Eutychides, Kucteniza, akin to genera from North America, 
Burma, and the Mediterranean; Hvagrus, ranging from North America to Bogota, 
is allied to genera from the Mediterranean region, West Africa, Transcaspia, China, 
and Burma. In the New World none of these groups is found south of the equator. 
In the Old World, however, genera akin to Bothriocyrtum, Enrico, Eutychides, 
Eucteniza, and Evagrus occur in South Africa, and others allied to Evagrus in 
Australia and New Zealand. Perhaps in the future these may be geographically 
linked with the northern types, but so far as our knowledge goes they are isolated. 
2. To the southern groups belong Neocteniza, from Demerara and Guatemala, and 
its ally Actinopus, which ranges from the Argentine into the West Indies and Panama 
and is related to the Australian genus Missulena, but to no other genus of the 
Old World; Fufius, extending from Brazil to Costa Rica and Guatemala, is related 
to many genera confined to South America and to others occurring in Madagascar and 
Australia, with one outlying form in the Mediterranean area; Ischnothele, ranging 
from the northern countries of South America into Mexico, is also met with in 
tropical Africa, Madagascar, and India; all the Central American genera of Thera- 
phoside, some of which pass into the Southern States of North America, have their 
nearest allies in South America, where they occur at least as far south as the 
