1918] Grinnell: A Synopsis of the Bats of California 257 
fig. 1). This valley is an old sea-bottom and at sea-level there are 
several caves worn in the rocky hillside by the one-time action of 
waves. Hight of these caves were examined by the party and five 
showed evidence of having been occupied by bats. <A portion of the 
floor of one of these caves was found to be covered to a depth of sev- 
eral inches with bat guano, and this was the cave where all the 
specimens were obtained. <A colony of fully three hundred of these 
bats was clustered in a funnel-shaped recess in the roof about thirty 
feet from the entrance. Disturbed by the light of the lantern the 
bats took wing and streamed out. Of the sixty-three taken, all but 
two were females and nearly every one contained a single large 
embryo; none was found to contain more. 
In the spring of 1914 the cave referred to above was visited by 
Donald R. Dickey, who states in a letter that he found it untenanted ; 
but a mile or so away another cave was found which contained a 
colony of bats. A number of individuals were caught, examined, 
and liberated. All proved to be California leaf-nosed bats. 
On the morning of Mareh 29, 1908, C. H. Richardson (MS) found 
a female leaf-nosed bat in a mouse trap set on the open ground near 
Mecea, Imperial County. The bat must have been entrapped while 
attempting to capture the ants or beetles which commonly visit traps 
for the oatmeal with which they are baited. It would appear that 
this species of bat may seek some of its food upon the ground. 
Dobson (1878, p. 466) states that a correspondent writing from 
St. Ann’s, Jamaica, remarks that Macrotus waterhousti there eats not 
only insects but also fruits. He mentions particularly the fustiec 
berry (Morus tinctoria), the bread-nut (Brosimum alicastrum), and 
the rose-apple (Hugenia jambos). It would be very interesting to 
learn whether our Californian Macrotus also eats fruit as well as 
insects ; if so, it is the only fruit-eating bat occurring within the state. 
Stephens (1906, p. 277) considers these bats as being probably 
migratory; for he failed to find them in January in a place where 
they were nearly always to be found in spring and summer. ‘The 
writer knows of no dates of capture within the state later than Sep- 
tember or earlier than March, save those furnished by Leo Wiley. 
There is in the Museum of Vertebrate Zoology an alcoholic. speci- 
men of Macrotus californicus (no. 23651), taken by this observer 
December 31, 1915, in an old mine shaft near Palo Verde. Mr. 
Wiley writes (MS) that he secured five more individuals of this 
species in the same shaft on February 20. 
