CORRODENTIA. 



Under the name Corrodentia are now assembled three very distinct groups 

 evidently closely related but differing so in habits and structure as to seem 

 to many to deserve rank as independent orders. The larger group usually 

 designated as the Mallophaga, the biting bird lice, have very evidently been 

 derived from the Psocina in rather recent times probably coincidently with 

 their hosts. The termites are very ancient and are the only group in the 

 order with abundant fossil remains, the others being of too small size and 

 delicate structure. 



SYNOPSIS OP FAMILIES. 



Philopteridae: antennae five-jointed. 



Liotheidae: antennae concealed, four-jointed. Gyropidae: feet with one claw. 



Trichodectidae: antennae three-jointed. 



Termitidas: feet four-jointed. Embiidae: thoracic segments as long as broad 



Psocidae. Atropidae: no ocelli. 



PHILOPTERINA. 



The bird lice are as a rule confined to one or a few related host species. 

 The following list gives the hosts of the California species. 



Grebe Docophorus lari, pertusus. Menopon tridens Nirmus fuscomarginatus. 

 Loon Docophorus columbinus, graviceps, lari. Lipeurus faralloni. Menopon 

 tridens. Puffin Colpocephalum perplanum. Nirmus pacificus. Auklet Docophorus 

 acutipectus, atricolor, montereyi. Nirmus maritimus. Murrelet Docophorus 

 atricolor, montereyi. Guillemot Docophorus procax. Nirmus fuscomarginatus, 

 paciflcus. Murre Docophorus calvus. Jaeger Docophorus melanocephalus. Nir- 

 mus triangularis. Lipeurus laculatus. Kittiwake Docophorus lari Nirmus lin- 

 eolatus. Gull Colpocephalum funebri. Docophorus lari. Menopon infrequens. 

 Nirmus felix, lineolatus. Tern Docophorus melanocephalus. Menopon tridens 

 Nirmus hebes, praestans. Albatros Colpocephalum pingue. Eurymetopus brevis. 



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