﻿34 Bulletin American Museum of Natural History [Vol. LVII 



BlBIONID^ffi 



Only a single species belonging to this family is represented in the 

 collection. 



Plecia Walker 



Plecia ruficollis (Fabricius) 

 Tipula ruficollis Fabricius, 1781, 'Spec. Insect.,' II, p. 410. 

 Eighteen specimens from the following localities: 2 males, 4 females, 



Faradje, Nov., 1912, and 1 female, March, 1912; male, Poko, Aug., 1913; 



9 males, 1 female, Stanleyville, Jan. to March, 1915. 



BOMBYLIIDiE 



The number of Bombyliidse in the collection is not large and but 

 few of the genera are represented. However, there are some interesting 

 forms and the records extend the distribution of many of the species. 

 Three of the forms are described as new, while there is evidently a fourth 

 undescribed species which is not sufficiently well preserved to warrant 

 its description. As the classification in this family is based largely upon 

 the color or arrangement of the pile, it is difficult to determine specimens 

 accurately unless they are in excellent condition, and, unless they are 

 collected and handled with great care (few being placed in a vial), they 

 lose not only their striking colors but become extremely difficult to place. 

 While a good many of the specimens are considerably denuded, it has 

 been possible to place almost all with certainty, owing to the excellent 

 revision of the family by Bezzi (1924, 'Bombyliidse of the Ethiopian 

 Region,' Brit. Mus. Nat. Hist.). Without this work, the determination of 

 African Bombyliidse is practically impossible, as the descriptions are so 

 widely scattered and there is little indication of the relationships of the 

 various forms. 



The genera represented in the collection may be distinguished by 

 means of the synopsis which follows. This is given merely as an indica- 

 tion of the genera which are most likely to be found and is of value only in 

 dealing with forms from a limited region. Many other genera probably 

 occur in the Congo. 



Synopsis of Genera 



1. Posterior border of the eyes not indented, seldom strongly emarginate; eyes 



without a short bisecting line near the middle behind 2. 



Posterior border of the eyes rather angularly indented and the eyes with a short 

 bisecting line at point of greatest indentation; occiput bilobate above .... 7. 



2. Prothorax strongly developed and bearing long, curved bristles. 



Toxopliora Meigen. 



