BUTTERFLIES OBSERVED IN DEAD HORSE CANYON, 
CALIFORNIA, DURING 1917 SEASON 
H. M. Simms 
Dead Horse Canyon is the largest of the small canyons branch- 
ing out of Verdugo Canyon on the western side and is situated 
near the southern end of the latter canyon. The entrance or 
mouth is small and inconspicuous, and as it is private property 
and opens into a large orange orchard it is not easy to find. 
There are several trails leading to the central and upper portions 
over a spur of Verdugo Mt. and the best of these is the one 
which starts from the top of Cambell St., Casa Verdugo, and, 
passing behind the reservoir, ascends to the crest of the spur in a 
northeasterly direction. At the summit of this ridge there is a 
wide trail which, leading to the northwest towards the summit of 
the mountain, passes the head of a steep but well defined trail 
about a quarter of a mile from the top of the first trail which 
leads down into the canyon at about the middle. Above the foot 
of this trail there is a somewhat overgrown trail following the 
bed of the stream up into the upper portion of the canyon. This 
upper portion is well wooded, the prevailing trees being Alder, 
Sycamore and Live Oak with a varied undercover in which Wil- 
low and Sallow predominate. The herbage is luxuriant and 
green throughout the summer. The lower portion of the canyon, 
i. e., the part below the foot of the trail from the ridge, is less 
wooded and the stream is dry during the greater part of the sum- 
mer whereas there is always water in the upper part. Neverthe- 
less there is a varied flora and plenty of bushes and near the 
mouth of the canyon there is a large grove of Live Oaks. 
During a considerable number of visits to this canyon from 
February to November of this year more than 50 species of but- 
terflies were observed and representatives of nearly all these spe- 
cies were captured. The following table is a brief summary of the 
observations made along this line : 
Papilio rutulus (Boisduval) "The Western Tiger Swallowtail." 
Common throughout the season, especially in the more 
wooded portions. 
Papilio eurymedon (Boisduval) "Eurymedon." 
Not uncommon in the earlier part of the summer. 
Papilio zelicaon (Luc). Seen once or twice in the spring on the 
ridge above the canyon. 
Pieris rapae (Linnaeus) "The Cabbage Butterfly." 
Common in the lower part of the canyon near the mouth. 
Pieris protodice (Bdv. and Leconte) (Reakirt) "The Common 
White." Common in the lower part of the canyon from May 
to late Fall. 
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