NESTING HABITS OF SOME ANTHIDIINE BEES. 265 



12 feet east. After ii3th trip (9:47) bee went to feed on Psoralea 

 plant. She was followed and was found to visit 83 flowers in 

 6 minutes. She then carried 3 loads into nest and fed again, 

 visiting 15 more. The I39th trip ended at 10 o'clock. 



The bee had no sooner alighted, after the I55th trip than a 

 male met her. The period of mating lasted 25 seconds after 

 which the female went on with her work as before. In one 

 instance she carried in a piece of old stem which was so long that 

 it was bent back to get into the hole. 



She made in all 240 trips between 8:50 and 10:26 at which time 

 the tunnel was filled even with the surface. This bee carried in 

 almost entirely pieces of dried mud; all others observed have 

 used mainly pebbles. The nest was dug up and consisted of 

 two cells. This nest was of the nature of those made by 

 Odynerus dorsalis Fabr. The lower cell was opened and con- 

 tained a small larva of A. porterx which later died. The 

 upper was not opened until in September at which time a 

 cocoon had been formed containing a live, mature larva. In 

 this instance one mating took place after the egg of the two 

 cells had been laid, both eggs hatching. It is probable that 

 A. porterx mates more than once. Other matings have been 

 observed to take place while the female was collecting pollen 

 for the cell. Once a female of this species was found to be 

 mating with a male, A. porterx amabile Ckll., a variety with 

 more red on the abdomen (h). 



The mass of pollen, semi-fluid in consistency, of the cell of 

 A. porters is 10 mm. long, flat on the top surface and curved on 

 the base. The egg lies flat on top of the mass of provision. A 

 larva 2\ mm. in length was found to be partially embedded in 

 the food. The exact larval period has not been ascertained 

 although a number of cocoons have been formed in the laboratory. 

 The larvae of those opened never developed much further and 

 it was thought that this might be due to the pollen drying out 

 as well as to possible mechanical injury (h). 



The size of the entire cell including the down varies a little, 

 due to the size of hole in which the down is placed. One which 

 was about average in size measured 17 mm. in length, being 

 12 mm. wide at the bottom and 10 mm. wide at the top. Pellets 



