SYSTEM OF -INSECTS. 397 



suborders, the Sedentaries and the Wanderers; thus 

 forming, perhaps, what Mr. MacLeay would denominate 

 the normal groups of a circle of Arachnida. 



DEF. Mandibles armed with a perforated claw. 

 Head and Trunk coalite. 

 Palpi pediform, anterior pair without claws. 

 Abdomen without segments or elongated tail. 

 Spiracles two 3 . 

 Anus furnished with an apparatus for spinning 5 . 



2. SCORPIONIDEA M C L. (Scorpio L. Latr.) 

 DEF. Mandibles chelate. 



Head and Trunk coalite. 



Anterior Palpi chelate c . 



Posterior Palpi pediform. 



Pectens two d . 



Abdomen divided into segments and termina- 

 ting in a jointed tail, armed at the end with a 

 sting e . 



Spiracles four pairs. 



3. GALE ODE A. 



DEF. Head distinct f . 

 Eyes two. 

 Mandibles chelate with dentated chelae. 



* PLATE XXIX. FIG. 1. b PLATE XV. FIG. 10. T". 



PLATE XXIII. FIG. 15. 17. T". c PLATE XV. FIG. 7. 



d PLATE XXVII. FIG. 50. 



e Called the Centris. VOL. HI. p. 388, 716. 



f M. Latreille thinks that in Galeodes the prothorax is coalite with 

 the head (N. Diet. d'Hist. Nat. xii. 370.) ; but that it is not so, is evi- 

 dent from the six real legs being affixed to the pieces behind it. See 

 also VOL. III. p. 23. note". 



