1894.] Subterranean Fauna of North America. 729 
I. The fauna of caves, subterranean waters and wells, and 
their origin, investigated by H. Garman, Herrerao, Girard, 
Bolivar, Cope and Stejneger. 
II. New facts regarding blind non-cavernicolous or lucifu- 
gous forms, comprising the anatomical and physiological in- 
vestigations of Eigenmann, Hess, Kadyi, Schlampf, Ritter, and 
others. 
III. Embryological observations on the conditions of the 
eyes in the young or in the embryos, tending to prove the 
origin of blind forms from normal eyed ancestors, by Teller 
and by Eigenmann. 
IV. Theoretical discussions, by Weismann, Herbert Spencer, 
Lankester, and others. 
I. It is very desirable to make a thorough survey of the ani- 
mal life living at present in the region around the entrances 
of caves, in order to ascertain the eyed forms from which the 
blind ones may have originated. This Professor Garman has 
begun to do for the cave-region of Kentucky. In his article in 
“Science,” on the origin of the cave-fauna of Kentucky,” while 
he remarks that “ the geological evidence is all that could be de- 
sired for proof of a recent origin of the caves themselves," he 
dissents “from the conclusions which have been drawn from 
this proof, as to the recent origin of the blind animals,” claim- 
ing that animals which burrow in the soil everywhere show a 
tendency: to loss of the organs of vision,” and that “ the origin- 
als of the cave species of Kentucky were probably already ad- 
justed to a life in the earth before the caves were formed,” 
and adds, “I cannot believe that there has been anything 
more than a gradual assembling in the caves of animals 
adapted to a life in such channels. In this view of the mat- 
ter the transformation of eyed into eyeless species appears to 
have been much less sudden and recent than has been sup- 
posed.” He illustrates his point by the “ definite example of 
the blind crustacean, Caecidotaea (Asellus) stygia, which, though 
first discovered in caves, is also widelyjdistributed in the upper 
Mississippi Valley, occurring as far east as Pennsylvania. “It 
is, throughout its range, a creature of underground streams, 
and is nowhere more common than on the prairies of Illinois 
