MOUTH T. I AH'S OF MOSQUJTO J.ARVAF. 
I go6] 
MOUTH PARTS OF MOSC^UFIT) LARVAK AS INDICA TIVK OF ITAJUTS. 
BY KVEI.VX MITCHELL, WASHINGTON, I). C. 
The larvae of tlie Culicidae follow the usual rule that a difference in the 
structure of the mouth jiarts is correlated with a corresponding difference in their 
fooil habits, d'his fact first forcetl itself upon the writer’s attention when 
studying the habits of the Louisiana species, while making drawings and dissec- 
tions for Dr. J. \V. Dupree, and was later confirmed when making dissections and 
tlrawings of larvae of additional species for Dr. Howard’s forthcoming mono- 
graph of this family. 
These larvae fall into two categories, viz.: i. Insectivorous, which, like Meg- 
arhinHs and Psorophora, normally prey upon small acpiatic larvae; and 2 . Non- 
.sectivorous, like Cu/ex, which feed on fc'.uglena and other protozoa, bacteria and 
vegetable matter; while between these groups are two others, somewhat interme. 
diate, viz.: the Uranotaenia and Anopheles groups. That the differences in habits 
are correlated with markeil differences in the structure of the mouth parts will 
be seen by the following critical comparison of the types of these four groups : 
