28 



majority. It is to be hoped that the present attempt to define 

 and describe our known sjoecies may induce others to take up this 

 promising subject. 



[n the present state of our knowledge, it is impossible to state 

 even an approximate number in respect of defined species. One 

 of the causes is that several authors have been simultaneously 

 and independently at work, with the result that the same species 

 has received different names, which can only be rectified by a 

 thorough revision in Europe by some one with means and leisure 

 to compare the types. 



Brunner van Wattenwyl (Nouveau Systeme des Blattaires, 

 1865), the highest authority on the suborder, describes 378 

 species in 56 genera, distributed all over the world, many of 

 which occur in two or more continents, but only two species are 

 wholly cosmopolitan, viz., Periplaneta orientalis and P. americana. 

 The following table will give a general idea of their distribution 

 as known at the date of Brunner's work : — 



Total of Endemic ^"^^""f^ ^°"^- 



c, . o • mon to two or 



hpecies. species. 



^ ^ more regions. 



Europe 18 U 4 



Asia and Malay Archipelago 89 62 17 



Africa, Madagascar, &c. ... 72 59 13 



North America, Mexico, W. 



India 52 41 11 



8outh and Central America 141 129 12 

 Australia, New Zealand, and 



Polynesia 48 38 10 



Habitat unknown ... ... 7 — — 



The number of endemic species is 343, and 35 are of wide dis- 

 tribution out of the total of 378. 



In Walker's British Museum Catalogue (1868) and the Supple- 

 ment (1869) a much larger number is recorded, but owing to 

 duplication of names, and absence of appreciation of some of 

 the most essential characters, great confusion has resulted, and 

 many of his species are quite uncertain. Since his time some 

 additions have been made by Saussure, Stal, and Bormans, com- 

 prising a moderate number of Australian forms (chiefly from the 

 eastern colonies and islands). Of the later publications of 

 Saussure, recorded by Walker, or of those of the two other 

 writers I have not been able to obtain sight, but expect to get 

 copies in the course of the year, when possible corrections will be 

 duly noted. 



In the present paper 193 species are recorded, being comprised 

 in 33 genera and 10 families, of which 1 family, 9 genera, and 55 

 species are new. The Periplanetidas are the most numerous with 



