ORTHOPTERA. 213 



radical joint in their enumeration, while others have 

 overlooked it, or regarded it merely as a point of 

 support to the palpus. Although frequently almost 

 lost in the substance of the labium, this joint appears 

 however to be always present, and although ap- 

 parently three-join ted, the palpi must therefore be 

 regarded as really composed of four articulations, 

 (Plate VI. fig. 6, c, c.) 



The tongue, (lingua?) generally a very obscure 

 member of the oral appendages, is very distinct in 

 some of the insects of this order. It is short, re- 

 tracted within the mouth, rather of a soft substance, 

 and in some instances, as in Blatta and Locusta, it 

 bears a pretty close resemblance to the tongue of a 

 vertebrate animal. 



The modifications of the antennae will be specified 

 afterwards as aiding in the discrimination of the 

 different groups. In general they are long, setace- 

 ous, and extremely flexible, consisting of fourteen, 

 sixteen, or twenty-five joints among different species 

 of Locustae ; of above thirty .among the Mantes ; 

 while in the Blattse or Cockroaches, the articulations 

 sometimes amount to 150, and vary even in indivi- 

 duals of the same species. 



Besides the ordinary compound eyes, which in 

 general are large and prominent, the insects of this 

 order are mostly provided with three simple eyes 

 situated in the crown of the head. In the genus 

 Blatta, the domestic cricket, and some other in- 

 stances, these auxiliary organs are wanting, but there 

 is a subdiaphanous space over the base of the antennae 



