The Bumble Bees of Los Angeles. 



A. Davidson, M. D. 



Bombus fervidus. Fabr. Is the most common of all the 

 bumble bees in the vicinity of Los Angeles. Along the shore, 

 especially at Redondo and Balboa it is quite common. Their 

 nests may readily be found among the rushes (Juncus) in the 

 marshy Hats along the coast. They are constructed of dry 

 grass and mossy fragments in the usual manner of the tribe 

 and may be hidden at the roots or shrubs or rushes or con- 

 cealed in the forsaken burrows of the ground squirrel. It is 

 impossible to explore their nests without protection for the 

 face and hands. No matter how carefully you approach them 

 or how gently the nest is opened, they attack one most 

 furiously. Perhaps the- frequent disturbances by hungry cattle 

 roaming these unfruitful pastures may have developed this 

 pugnacity for their successful existence. In the interior they 

 are not at all common though they range inland as far as the 

 New Mexican border. 



B. sonorus Say. Is fairly common on the coast and has 

 been collected inland through the ranges around the Mohave 

 desert to Inyo County and at Palm Springs in the Colorado 

 desert. 



B. Californicus Smith. Most commouly found on the 

 coast beaches and at Catalina ; less frequently in the San 

 Bernardino Mountains up to 6000 feet altitude. 



B. Columbicus (Dall Torre). More common than the last 

 with the same range in Southern California. 



I found this species in the Sequoia Natl. Park, but none 

 of B. californicus of which it is supposed to be but a variety. 



Mr. T. D. Cockerell has suggested that they may be dis- 

 tinct species and the larger size of the males of the latter would 

 bear this out. I have sought in vain for the nests of these two 

 species in the endeavor to definitely determine their relative 

 status. Personally I think they are distinct species. 



B. edwardsii Cress. In the Sierra's at Sequoia Natl. Park 

 this insect is fairly common. It is somewhat rare in the San 

 Bernardino Mountains and our coast range. At San Fernando 

 I found a colony warmly housed in the nest of a cactus wren. 

 At that time, (May) it contained thirty individuals. 



B. juxtus Cress. Six specimens captured at Seven Oaks 

 and Bear Valley, San Bernardino Mountains. 



B. nevadensis Cress. One specimen on Wilson's Peak. 



B. morrisonii Cress. One specimen on the trail to Wil- 

 son's Peak. 



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