﻿388 Lovell : The Insect- Visitors of Flowers 



L. comicina Fab.: (15) Morellia mic'ans Macq.; (c) Anthomyidae : 

 (16) Phorbia fuscipes Zett; C. Coleoptera — (a) Elateridae : (17) 



ipiens Harr. July 19-J 



■>P> 



Corxus ALTERNiFOLiA L. Alternate -leaved Cornel. 



As the flower expands the anthers and stigma mature simul- 

 taneously. The style is 3 mm. long and the stamens 6 mm. so 

 that cross-fertilization would be favored by different parts of the 

 bodies of insects coming in contact with the anthers and stigma. 

 The open white cymes are very numerous and conspicuous, honey 

 is secreted by a green, fleshy ring at the base of the style, odor 

 faint, pleasant. In comparing the three preceding species of 

 Cor nus, it is noteworthy that in C. Canadensis L., where conspic- 

 uousness is gained by means of an involucre, the flowers are 

 smaller, more closely set, there is effective provision against self- 

 fertilization and a less abundant supply of honey ; an arrangement 

 that permits the honey-bee to visit the flowers so rapidly that the 

 rate per minute could not be determined satisfactorily. 



Hymenoptera are the most important agents in inter-crossing 

 C. alternifolia L. ; diptera are common but play a subordinate part 

 compared with the bees ; coleoptera are not common. 



Visitors : A. Hymenoptera— (a) Apidae: (1) Apis mellifica L., 5 , 

 common, sucking ; (2) Bombas terricola Kirby, $ , rare ; {b) An- 

 dremdac: (3) Andrena eonw/odaSm., 9 , common, collecting pollen; 

 (4) A. designate Ashm. $ ; (5) Andrena (?) viola Rob., 9 common ; 

 (6) Halictus si wilis Sm., $ ; (7) Halictus sp.; (8) Sphecodes deckroa 

 Sm., $, rare ; (9) Agopostcmon radiatns Say, 9 , rare ; (c) Eumeni- 

 dae: (10) Ancistroceras copra Sauss.,^. B. Diptera— (a) Syr- 

 phidae : (1 1) Syritta p ipiens L.; (12) Syrphns rifesii L.; (13)^* 

 pistieoides Will ; (14) Chilosia sp.; (15) Helophilns latifrons Loew : 

 (16) Temnostoma alter nans Lw.; (b) Muscidae : (17) Pollenia rudis 

 Fab.; (V) Sarcophagidae : (18) Helicobia he lids Town.; (d) Chiron- 

 omidac: (19) Ceratopogon sp. C. Coleoptera— (a) Carabidae : 



>) Lebia viridis Say ; (b) 



:pt 



■a 



lined* 



, , (c) Cephaloidae: (22) Cephaloon Icptnridcs Newn.; (d) C&f 1 ' 

 dae : (23) Isomera qnadristriata Coup.; (e) Anthicidae : (24) u " 

 phyra Ingubris Say ; (/) Chrysomelidae : (2 s) Chrysomela scale* 



