848 THE AMERICAN NATURALIST. | [Vor. XXXIV. 
many simple ancestral characters with others, which, like the 
reduction or absence of eyes, tracheze, etc., may be interpreted 
as the effects of degeneration. Till the internal structure of 
Keenenia has been studied and compared with that of other 
arachnids, it is hardly possible to make more precise state- 
ments than the above concerning its phylogenetic relation- 
ships. 
The statements made by Grassi and Hansen and Sörensen 
concerning the conditions under which Koenenia lives in Sicily 
and southern Italy may be repeated almost verbatim for the 
Texan specimens. I have found them most abundant along 
the margin of a cedar thicket on a rocky hill (altitude about 
700-800 feet), only a few minutes' walk from the campus of 
the University of Texas. They occur under stones rather 
deeply imbedded in the ground but easily overturned. The 
earth under these stones is of a very definite degree of moisture, 
which one soon learns to recognize when searching for speci- 
mens. The animals are found crawling over the surface of the 
_ Stone, very rarely on the impressed soil. Sometimes four or 
. five will be found on a single stone. They are very agile and 
easily escape into some crevice or under the particles of earth 
adhering to the stone. They are most easily captured, as - 
Hansen and Sórensen have shown, by means of a fine brush 
dipped in alcohol. 
In Europe Keenenia was found associated with Iapyx, Cam- 
podea, Pauropus, and Scolopendrella. In Texas it is associated 
with the very same series of forms, excepting Pauropus, which 
I have not yet seen in this locality. I am inclined to believe 
. that the arachnid feeds on the eggs of Campodea or Iapyx. T 
infer this from the fact that the intestine and its short diver- 
ticula are always filled with something very much like the yolk- - 
bodies of an arthropod egg. Moreover, the Koenenia was most 
abundant where the very young Campodea and Iapyx lived in 
greatest numbers. 
_ The association of a group of fortis like Koenenia, Iapyx, 
Campodea, and Scolopendrella — all very small, primitive, and 
: synthetic types, and all devoid of pigment and visual organs— 
s in two Menem so ide 
MW 
ted as ge and Texas, is of i; * : x 
