la all tlie works of Fabricius, published between 1775 and 1793, he 

 included these insects in his class Ulonata, dividing them artificially 

 — by the structure of the antennse — as follows: 



I. Acrydium (Tetricides). 



Gryllus (Acrydii). 

 n. Truxalis. 

 in. Forficula. 

 Blatta. 

 Mantis. 



Acheta (Gryllides). 

 Locusta (Locustaria;.) 



But in the body of his works he always followed a different succes- 

 sion of genera, viz. : Forficula, Blatta, Mantis, Acrydium, Truxalis, 

 Acheta, Locusta, Gryllus. 



DeGeer, in the third volume of his Histoire des Insectes, published 

 in 17 73, applies the name of Dermaptera to this group, and divided 

 it into the genera Mantis, Locusta (Locustariaj), Acrydium (Acrydii), 

 Gryllus (Gryllida;), Blatta and Forficula. 



Latreille, in bis Precis des caracteres generiques, published in 

 1796, divided the Orthoptera into three groups, as follows: 



I. Forficula. 

 II. Blatta. 

 in. Fam. 1. Gryllus (Gryllides). 



Locusta (Locustarise). 

 Mantis. 

 Fam. 2. Truxalis. 



Acrydium (Acrydii). 

 Acheta (Tetricides). 



In his subsequent works, he has uniformly maintained one succes- 

 sion of genera, but has greatly varied his larger divisions at different 

 times. In 1801 and 1807 he arranged the Orthoptera under three 

 unnamed sections, as follows: 



Sect. I. Forficula. 

 " II. Blatta. 



'' in. Fam. 1. Mantidcs I l^^^f^^ ^^^^f^^]' ^ 



( Kaptatonte (Mantides). 



. . " 2. Grylllse. 



" 3. Locustariaj. 

 ** 4. Acrydiana. 



