NESTING HABITS OF SOME ANTHIDIINE BEES. 



CLARENCE P. CUSTER AND CHARLES H. HICKS. 



The habits of the Anthidiine bees have been studied by Fabre 

 (2), Friese (3), Davidson (i), Melander (7), Newberry (8), 

 Hungerford and Williams (6), Hicks (5), and others. Fabre 

 early considered the genus Anthidium to consist of two groups, 

 divided primarily on habits. One he termed "cotton-workers"; 

 the other "resin-workers." The former now comprise the genus 

 Anthidium; the latter Dianthidium. The habits of these bees 

 have not been studied so thoroughly in America as in Europe. 

 Studies of Anthidium porter se, Ckll. have been made by Hunger- 

 ford and Williams (6) and Hicks (5), and Dianthidium sayi 

 Ckll. by Hicks (5). 



The writers are indebted to Dr. T. D. A. Cockerell and to 

 Dr. Francis Ramaley for helpful suggestions and for the determi- 

 nation of specimens; to Dr. Edna Johnson for the determination 

 of some plants; and to Mr. S. A. Rohwer for determining some 

 wasps. 



We continued a study of these bees during the summer of 

 1926. The following is an account of our work. 



Anthidium porterx Cockerell syn. maculifrons of authors, 



not Smith. 



Hungerford and W 7 illiams (6) state that two females of this bee 

 were observed nesting in a bank of coarse, quartz sand near a 

 colony of bembecid wasps. The down of the cells of the nest 

 was thought to be derived from thistle (Cirsiurn) stems or from 

 the inflorescence. The tunnel of one was 10 inches long. 



Most of our study of this species has been done at Point East l 

 and at Base Line Lake, 2 near Boulder, Colorado. The nests have 

 been found both on hillsides and on level ground, usually in bare 

 areas. 



1 A small hill rising above the plains, 3 miles east of Boulder. 



2 Six miles east of Boulder on the plains. 



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