Chap. XI. PERFORATION OF THE COROLLA. 435 



flies away in search of another bitten flower. Never- 

 theless, I once saw a humble-bee visiting the hybrid 

 Rhododendron azaloides, and it entered the mouths 

 of some flowers and cut holes into the others. Dr. 

 H. Muller informs me that in the same district he has 

 seen some individuals of Bombus mastrueatus boring 

 through the calyx and corolla of Rhinanthus alectero- 

 loplius, and others through the corolla alone. Different 

 species of bees may, however, sometimes be observed 

 acting differently at the same time on the same plant. 

 I have seen hive-bees sucking at the mouths of the 

 flowers of the common bean ; humble-bees of one kind 

 sucking through holes bitten in the calyx, and humble- 

 bees of another kind sucking the little drops of fluid 

 excreted by the stipules. Mr. Beal of Michigan 

 informs me that the flowers of the Missouri currant 

 {Riles aureum) abound with nectar, so that children 

 often suck them ; and he saw hive-bees sucking 

 through holes made by a bird, the oriole, and at the 

 same time humble-bees sucking in the proper manner 

 at the mouths of the flowers.* This statement about 

 the oriole calls to mind what I have before said of 

 certain species of humming-birds boring holes through 

 the flowers of the Brugmansia, whilst other species 

 entered by the mouth. 



The motive which impels bees to gnaw holes through 

 the corolla seems to be the saving of time, for they 

 lose much time in climbing into and out of large 

 flowers, and in forcing their heads into closed ones. 

 They were able to visit nearly twice as many flowers, 

 as far as I could judge, of a Stachys and Pentstemon 



* The flowers of the Ribes are through and rob seven flowers 



however sometimes perforated by of their honey in a minute: 



humble-bees, and Mr. Bundy says ' American Naturalist,' 1876, p. 



that they were able to bite 238. 



2 f 2 



