CLASSIFICATION OF ARTHEOPODA. 231 



Autaraci.n£e {continued). 



Linguatulina. 



Pentastomum. 



Pseudaraclinas*). 



Tardi gratia. 



Macrobiotus. 

 Pycnogonida. 



Pycnogonmn, Nymplion. 



II. Myriapoda. 



Cliilopoda. 



Scolopendi-a, Lithobius. 

 Chilognatha. 



Polydesmus, Julus, Glomeris. 



III. Insecta (Hexapoda). 



1. Apterat). 



CoUembola. 



Symnthurus, Potlura. 

 Thysaniira. 



Campodea, Lepisma, Macliilis. 



2. Pterygota. 



Pseudoneuroptera. 

 Amphibiotica. 



Ephemera, Chloe, Perla, Libellula, AgrLon, ^sclma. 

 Corrodentia. 



Psocina. 



Psocus, Troctes. 

 Embida. 



Embia. 

 Thysanopoda. 



Thi-ips. 

 Termitida. 

 Termes. 

 Nenroptera. 



Planipennia. 



Panorpina. 

 , Panorpa, Bittacus. 



Sialida. 



Rhapliidia, Sialis. 

 Hemerobida. 



Hemerobius, Cbrysopa, Myrraeleon. 

 Trichoptera. 



Phryganida. 



Phryganea, Limnopliilus. 

 Strepsiptera. 



Stylops, Xenos. 



* Very divergent forms are formcl in both divisions of the Pseudarachn^, and 

 have really very little in common except their divergence from the Autaraohnse. It is 

 not quite certain that the Tardigrada have any relations to the Tracheata. 



t The two groups united in the division of the Aptera are removed from all 

 other Insects, owing to the difference in theii- organisation; we cannot therefore place 

 them with any one order. Though they have much in common with the Pseudo- 

 neuroptera, it is because the latter are so low. Their want of wings must be_ re- 

 garded as a primitive condition, as compared with the adaptative wingless condition, 

 examples of which may be seen in nearly all orders of the Pterygota. 



