34 Lransactions of the Academy of Science of St. Louis 
In San Mateo County, where the two species are found 
together, the San Francisco Alligator Lizard evidently mates 
several weeks earlier than does the Red-backed Alligator Lizard. 
At Daly City, on August 14, 1932, young of coeruleus were 
seen in abundance, but apparently the young of G. m. multi- 
carinatus had not yet hatched, as none at all was seen. 
On one occasion when a large skink, Eumeces skiltonianus, 
and a young G. c. coeruleus were placed together in a cage, the 
Skink ate the alligator lizard, swallowing it head first. Its tail 
was broken off and was not eaten 
Daly City, on September 18, 1932, the head and 
coeruleus were found on top of a large boulder where they had 
evidently been discarded by some predator. Probably the lizard 
had been caught and eaten by a sparrow hawk, as one of these 
birds was seen on the same boulder earlier in the afternoon. 
NVhen a large adult male coeruleus was offered to a captive 
sparrow hawk, the bird flew down and caught it at once, taking 
it by surprise. The lizard twisted about, partly freed itself and 
bit at the hawk, which released it and jumped back. Renewing 
the hawk hopped around the lizard, 
stamping its feet and preparing to strike. The Gerrhonotus 
made no attempt to escape but assumed a characteristic defen- 
Sive attitude, standing high off the ground with its body thrown 
in an arc, head and tail pointing toward the bird and with its 
mouth open. It was breathing heavily with a faint whistling 
an attempt to free itself. After this the hawk was wary but 
finally approached again, i i 
breast feathers. The hawk grasped the lizard with one ft 
-Temoved. The lj ; 
skin had not been penetrated by the hawk’s talons, 
Several kinds of snakes probably prey upon these lizards. 
garter snake -(Thamnophis ordinoides atratus) which I col- 
lected at Moss Beach, San M 
Nematode worms are sometimes abundant in the stomach 
and intestines of these lizards, Flukes hay been found in their 
