HOWELL — THE CALIFORNIA MASTIFF BAT 
113 
My first mastiff was secured October 23 from the ridgepole of a large, 
abandoned packing house a mile from my home near Covina, Los 
Angeles County, and was in such a position that we had to shoot it. 
This is not a regular roost, for there are few or no dark nooks for hiding, 
but its vicinity is a favorite hunting ground for several species of bats, 
and the mastiffs occasionally use it for a day or two at a time, for I 
found another there later in the winter. 
The next find was near Colton, San Bernardino County, and was 
located through W. C. Hanna, to whose kindness we are especially 
indebted. It was situated in a crack between an outside timber and 
the wall of an old stone building, with a sheer drop below it of about 
thirty feet. On this building there were other similar situations, but 
there was a little old guano beneath only one other crack. This roost 
contained at least forty, and possibly sixty bats. Little, Hanna and 
I visited this on November 5, when eighteen were secured, equally 
divided between the sexes. Another visit was made to this colony 
November 24 and twelve more captured, but we could tell nothing in 
regard to the number remaining, except that there were quite a few 
crowded into a dark corner. On April 23 there were no bats there. 
I do not believe that our activities drove them away, for I have taken 
every bat from a colony and found more later. Rather do I think that 
they temporarily sought some other location for breeding, or that it 
was used as a winter roost only. However that may be, a less suitable 
spot for wintering it would be difficult to find. The stone which 
bounded one side of the cranny was very cold, of course, and in addition, 
the aperture of the space occupied was fully as large above as below, 
with nothing to shelter the inmates when the cold, driving rain of the 
winter storms beat upon them. Still, there were the desiccated remains 
of but two, and that is an unusually low mortahty. 
Another small colony was discovered March 20 in a large house within 
a short distance of my ranch. Previously, the bats had occupied the 
attic, but their noise was such a nuisance that the ventilators were 
covered with netting and the twenty or thirty bats thus imprisoned 
were caught and killed. At the time of my visit, I found two live bats 
between the slats of one ventilator, and in another, four, one dead and 
blown with small maggots, another dead only a few hours, and two 
others which were decidedly weak. This was at the end of a spell of 
cold, rainy weather, but I cannot see why these should die of cold and 
hunger while those secured on the eighteenth were fat and lively. A 
possible explanation is that the latter were in a protected situation, 
