OF WASHINGTON, VOLUME XV, 1913. 29 



pie, cannot be relegated to their proper position, because the 

 calyptra are not noticeably dissimilar in size as required by the 

 table. In examining large numbers of Diptera during the last 

 10 years, submitted form various Institutions and individuals in 

 England and Scotland, it has been impressed upon me that the 

 more macrochsetae a species has the more prone they are to vary 

 in number and strength, and the larger the number of veins, such 

 as in the Therevidse, Tipulidse and Asilidae, the more variation 

 there is in the number and course of those veins. It is rarely 

 the case in species without recurrent veins that there is much 

 variation, though I have seen several specimens, probably about 

 half a dozen, out of about 7000 or 8000 Phloridae examined in 

 which abruptly terminated, instead of complete, veins occurred, 

 or in which a small appendiculate vein was present, or a fork 

 absent. In such cases only a thorough knowledge of the group 

 will give one the necessary basis for identification. Arbitrary 

 tables fail with abnormal specimens in any order, and the general 

 habitus of the insect coupled with special knowledge must nec- 

 essarily serve for identification purposes. 



Mr. Schwarz remarked that in Coleoptera macrochaetae are to 

 be found in many parts of the body and are successfully used as 

 specific characters especially in Carabidse and Staphylinidse. As 

 far as the North American. fauna is concerned, Dr. Leconte was 

 the first to call attention to their importance. In many instances 

 the macrochaetae are lost but the pores remain and are remark- 

 ably constant in their position, for instance in the genus Platynus. 

 They do not seem to occur in the large phytophagous families, 

 at least not in the imago stage, unless we consider the sensitive 

 hairs on the antennae of certain Cerambycidae and Rhynchophora 

 as macrochaetse. 



The third paper on the program was read by Mr. Thomas E. 

 Snyder: 



