CAMrODEA. 133 



Our common American species of Campodea (C. Americana) 

 lives under stones in damp places. It is yellowish, about a 

 sixth of an inch in length, is very agile in its movements, and 

 would easily be mistaken for a very young Lithobius. A larger 

 species and differing in having longer antennte, has been fouiTd 

 by Mr. C. Cooke in Mammoth Cave, and has been described 

 in the "American Naturalist" under the name of 'Campodea 

 Cookel. Haliday has remarked that this family bears much 

 resemblance to the Neuropterous larva of Perla (Fig. 155), as 

 previously remarked by Gervais ; and the many points of resem- 

 blance of this family and the Lepismidte to the larval forms of 

 some Neiiroptera that are active in the pupa state (the Pseudo- 

 neuroptera of Erichson and other authors) are very striking. 

 Campodea resembles the earliest larval form of Clijoeon, as 

 figured by Sir John Lubbock, even to 

 the single jointed tarsus ; and why these 

 two Thysanurous families should be 

 removed from the Neuroptera we are 

 unable, at present, to understand, as to 

 our mind they scarcely diverge from the 

 Neuropterous type more than the Mallo- 

 phaga, or biting lice, from the type of 

 Hemiptera. 



Haliday, remarking on the opinion of 



Linnajus and Schrank, who referred 



^ , i ii 11 T) 1 Fig. 155. Larva of Perla. 



Campodea to the old genus rodura, says 



with much truth, "it may be pei'haps no unfair inference to 

 draw, that the insect in question is in some measure inter- 

 mediate between both," i. e., Podura and Lepisma. This is 

 seen especially in the mouth-parts which are withdrawn into 

 the head, and become very rudimentary, aflbrding a gradual 

 passage into the mouth-parts of the Podurida;, which we now 

 describe. 



The next group, the Podurelles of Nicolet, aru;l Collembola 

 of Lubbock, are considered by the latter, who has studied them 

 with far more care than any one else, as "less closely allied" to 

 the Lepismidse "than has hitherto been supposed." He says 

 " the presence of tracheae, the structure of the mouth and the 

 abdominal appendage, all indicate a wide distinction between 

 the Lepismidre and the Poduridse. We must, indeed, in my 

 opinion, separate them entirely from one another; and I would 

 12 



