172 The Ottawa Naturalist. [Mar. 



Denmark and Southern Scandanavia nearly all the species are 

 much darker than usual. Surrounding this region is a wide 

 circle including Britain and the Swiss Alps, in which the species 

 are less extensively darkened. Outside this circle, for example, 

 the Pyrenees and Northern Scandanavia, there is hardly any 

 tendency to melanism. A colour scheme common to Europe 

 and America is dull yellow with a black inter-alar band. The 

 dominating pattern in North America is pale greenish yellow 

 with a broad black tail, exemplified in Bombus vagans, perplexus 

 and impatiens. Another North American pattern is pale yellow 

 with a black band across the thorax and a red band across the 

 abdomen. These instances of regional convergence are some- 

 times stronger in the queen than in the male, and Mr. Sladen 

 suggested that this might be because the queen probably needs 

 to display warning colours more than the male on account of 

 a period in the life cycle of the bumble bee, lasting about a 

 month, in which the existence of the race depends upon a small 

 band of slow-flying, heavily-laden queens that would easily 

 fall a prey to any bird that might care to pursue them. Mr. R. I. 

 Pocock, Curator of the London "Zoo", found that bumble bees 

 were distinctly distasteful to birds. 



Dr. Hewitt brought forward a recently published monograph, 

 by Dr. F. W. Cragg, of the Indian Medical Service, on the com- 

 parative anatomy of the proboscis in the blood-sucking flies, 

 in which the author shows that these flies can be arranged in a 

 series commencing with those flies which are blood-suckers by 

 habit but have no biting mouth parts, namely, certain species 

 of Musca, and passing on through those which are provided 

 with more or less efficient biting organs, such as Philaematomyia 

 and Hcematobia, to those forms, such as Stomoxys and Glossina, 

 which have entirely lost the characteristic structure of the 

 labella by means of which the non-biting flies absorb nourish- 

 ment. The probable evolution of the blood-sucking muscidae 

 from the non-blood-sucking forms has a possible bearing on the 

 the theory concerning the origin of the Haemoflagellates. 



Dr. Hewitt also called the attention of the members to 

 Dr. Graham-Smith's recent book on " Flies and Disease " in which 

 he brings forward a greater amount of evidence, chiefly original, 

 in regard to the dissemination of bacteria than has hitherto 

 been submitted by any investigator in the field. 



Mr. Harrington showed specimens of the Cotton Boll 

 Weevil, and referred to the enormous damage done by this 

 insect in the Southern States. Dr. Hewitt said that at the recent 

 Meeting of the Entomological Society of America at Atlanta, 

 Dr. Hinds had read a most interesting paper in which he showed 



