SYNOPSIS. XV 



fications like the vertical motion of the jaws of Balaninus, 165. 

 Footless grubs, 165. General remarks on the classification of 

 the Coleoptera, 165; affinities with Orthoptera and Hemiptera, 

 1 66; retention in many groups of Thysanuriform larva, and of 

 generalized characters in the adults, 166. Tendencies to pro- 

 duction of wing-covers, and differentiation of prothorax shown 

 in orders VI., VII., and IX. carried to an extreme in Coleop- 

 tera, 166. Sessile abdomen possessed by beetles in common 

 with the more generalized insects, 166. Larvae with biting 

 mouth parts, consequently less widely removed from Thysanuran 

 standard than sucking larvae of Hemiptera, 166, 167. Larvas 

 of other Coleoptera cylindrical grubs with few Thysanuran char- 

 acters, 167; larvae of most weevils footless grubs with no Thysa- 

 nuran characters, 167. Development of Meloe and Sitaris tend 

 to prove that the hexapod grub is a derivative from the Thysa- 

 nuriform larva, and the footless grub from the hexapod form, 

 167. Evolution of the Rhynchophora, 168. 



ORDER XI. — NEUROPTERA. 



Structure of Corydalus, 170; unconsolidated wing-bearing seg- 

 ments, large size of wings, slow movements, 170; power of flight 

 not wholly dependent upon comparative size of wings, 171; 

 significance of term " Neuroptera," 171. Egg-mass of Corydalus, 

 171; larval characters, tracheal gills, and spiracles, 171, 172. 

 Hemerobidfe, 172. Structure of lace-winged fly, 172. Manner 

 of laying eggs, 173. Carnivorous habits of larvas, 173. Cocoon of 

 pupa, 173. Habits of ant-lions, 174. Brauer on life-history of 

 Mantispa, 174. General remarks on Neuroptera, 174, 175; the 

 primitive form of larvae as compared with larvae of succeeding 

 orders, 175. Derivation from a Thysanuroid ancestor through 

 some intermediate winged insect, 175; difficulty of determining 

 with certainty this intermediate winged form, 175. 



ORDER XII. — MECOPTERA. 



Structure of Panorpa, 176; small prothorax like that of Lepi- 

 doptera, 1 76. Length of wings, significance of term " Mecoptera," 

 176. Biting mouth parts at the end of a rostrum, 176. Cater- 



