132 Bulletin of Laboratories of Denison University [Voi. xi. 
may be seen after a cold night imerging from the sauce-like de- 
pression so made. 
Like many others we long regarded the statement that 
these animals sometimes discharge a qauntity of blood from 
their eyes when disturbed as a fable. Upon a single occasion 
however we have had an opportunity to verify this statement. 
So far as we could discover the animal was not injured and we 
have handled others much more roughly without such a result 
but in this case (P. cornutum) a large drop of a red fluid was 
thrown out from the eye and moistened its head as well as the 
hands of the intruder. 
Although the most peaceful of animals, the horned toads 
defend themselves with energy. The writer once witnessed a 
contest between two large lizards (Crotophytus) and a very 
large specimen of P. douglassii. The toad threw himself into 
the most amusing posture of defense by kneeling down with the 
legs of one side while standing on tip toe with the opposite set 
and thus presenting the shield-like dorsal surface to the enemy. 
With a single opponent these tactics succeded well and the liz- 
ard received some shrewed thrusts with the powerful horns, but 
when there were two foes it was easy for one to take advantage 
of the weaker side and sieze the toad in the soft region under 
the neck where he hung with a grip not to be shaken off. 
KEY TO THE GENUS PHRYNOSOMA. 
The following key is largely a compilation from various 
sources and we suspect that there may be synonyms or at most 
geographical races among the species enumerated. It is hoped 
that the table such as it is may nevertheless be serviceable. 
A. Nostrils opening on or near the lines connecting the supra- 
orbital ridges with the end of the snout (canthi 
rostrales). 
a. Gular scales small, nearly equal in size; a series of enlarged 
scales below, but not larger than, the lower 
labials. 
b. Head spines short (variable); occipitals shorter than the 
transverse diameter of the eye ball. P, douglassii. 
