ORTHOPTERA — LOCUSTIDiE. 53 



it with a light. It will move but a dozen feet or so, however, and if 

 followed that far will be nearly as easy to approach as before. This 

 Ceuthophihis feeds upon organic matter. It was seen feeding upon the 

 decayed carcass of a mouse, and on several occasions was found feeding 

 upon cheese left as bait. It is sometimes found near decaying organic 

 matter of any sort. 



According to evidence obtained this species seems to breed during 

 the fall. Adults were found in but small numbers and only during 

 September and October. No adults were seen farther back than " 12. " 

 Adults of this species were seen in White's Cave, Kentucky, about 

 November 25, 1903. Young appeared near the mouth of Mayfield's 

 Cave early in October and were seen from then until December and in 

 one case in February. No adults or very small individuals were seen at 

 other times than those mentioned. Hence it seems that the adults 

 occur in the cave during the summer and fall, and that they breed and 

 soon disappear, the young appearing in October and later. From the 

 size of individuals which I take to be a year old this species must require 

 at least two years and probably three years to mature. The eye was 

 moderately well developed, as Lawrence Durborow, who has given some 

 study to the structure of the eye of this animal, has found. 



As is well known, ceuthophili commonly live under rotten logs in 

 shady woods, about wells and cellars, and in damp, dark places generally. 

 Ceuthophihis stygius has several cave-inhabiting relatives. C. ensifer 

 (Packard, 1888, 71) is found in Nickajack Cave, Tennessee; C. palmeri 

 (Scudder, 1894, 41) lives in Bat Cave near Georgetown, Texas, in Beaver 

 Cave, and in other localities of Texas; in Florida one species of this 

 genus lives in holes of the gopher turtle and in hollow trees; C. mexicanus 

 (Scudder, 1894, 82) is found in caves at San Pedro and San Lorenzo, 

 where it lives among mummies; Hadensecus suhterraneus (Packard, 

 1888, 69 ff . ) , another relative, is extremely abundant in Kentucky and 

 Tennessee Caves; Phalangopsis annulata Bilmek (1867, 904) occurs in 

 Cacahuamilpa Grotto in Mexico. There are 2 genera and at least 5 

 species of ceuthophili which inhabit European caves. 



Order APTERA. 



Suborder THYSANURA. 



Family LEPISMIDAE. 



Machilis variabilis Say. 



Say, Phila. Acad. Nat. Sci., ii, 1821, 12. Packard, Am. Nat., 1871, v, 746 (Mammoth 

 Cave). Lubbock, Collembola and Thysanura, 240, London, 1873. 



Often seen from the door to the first turn. It occurs sometimes on 

 the wall, but more often on the roof. This is a common species in humid 

 places in the United States. This genus was recorded from Wyandotte 



