CHAEACTEES IN THE TABLES 7 



thinus) the species separate on the shape of the side-pieces and the form of the 

 clasp filaments; next the degree of reduction of the filament, which in some 

 forms becomes fimctionally replaced by the produced outer angle of the side- 

 piece ; then the details of the structure of the modified and lobed clasp-filament, 

 and in some cases' by the shape of the harpes. In Lesticocampa and Johlotia, 

 the basal appendages express the first dichotomy, followed by modifications of 

 the side-pieces and harpes. The structures which we call harpagones in the 

 descriptions of the genitalia are not homologous with what we call harpagones 

 in the Culicini, being here more like a second pair of imci. But they occupy a 

 similar position, and it appears to us more likely to cause confusion if a separate 

 term were employed. 



In the Culicini, the genitalia show a wider range of structure and are largely 

 available for generic definition. Harpes and harpagones are absent in the lowest 



A. Side-piece. 



B. Clasp-fllament. 



C. Lobes of side-piece. 



D. Harpe. 



E. Harpago. 



F. Unci. 



G. Basal appendage. 



forms, the harpes appearing first. The presence of lateral appendages to the 

 side-pieces separates the genera allied to Deinocerites and Cidex, except for a few 

 aberrant forms ; Mansonia is characterized by a rod or tooth set in the end of the 

 harpagone; Psorophora by another modification of the harpagone, and Ramor 

 gogus by a fringe of large scales on the side-pieces. A few aberrant forms come 

 out separately in the table. In the Deinocerites group, the species separate by 

 small details. In Culex, after separating the aberrant dyari and melanurus, the 

 species separate broadly on the modifications of the lateral prominence of the 

 side-piece, the shape of the harpes, and lastly the fine divisions of the harpa- 

 gones. These serve for minute specific characters, but have not been carried out 

 to the final details in the tables, largely for want of time for the minute com- 

 parative study. They are indicated, however, in our figures, to which reference 



