CHAPTER II. 



THE ZOOLOGICAL POSITION OF THE COCKROACH. 



Sub-kingdom ARTHROPODA. 



Class I. Crustacea. 



,, II. Arachnida. 



,, III. Myriopoda. 



,, IV. INSECTA. 



Order 1. Thysanura. 



,, 2. Orthoptera. 



,, 3. Neuroptera. 



,, 4. Hemiptera. 



,, 5. Coleoptera. 



, , 6. Diptera. 



,, 7. Lepidoptera. 



,, 8. Hymenoptera. 



THE place of the Cockroach in the Animal Kingdom is illus- 

 trated by the above table. It belongs to the sub-kingdom 

 Arthropoda, to the class Insecta, and to the order Orthoptera. 



Characters of Arthropoda. 



Arthropoda are in general readily distinguished from other 

 animals by their jointed body and limbs. In many Annelids 

 the body is ringed, and each segment bears a pair of appendages, 

 but these appendages are soft, and never articulated. The 

 integument of an Arthropod is stiffened by a deposit of the 

 tough, elastic substance known as Chitin, which resembles horn 

 in appearance, though very different in its chemical composition. 

 In marine Arthropoda, as well as in many Myriopoda and 

 Insects, additional firmness may be gained by the incorporation 

 of carbonate and phosphate of lime with the chitin. However 

 rigid the integument may be, it is rendered compatible with 

 energetic movements by its unequal thickening. Along defined, 



