297 
ing concealed between the roots of the plant or in the angles 
between leaf and stem the animal is surely never exposed to 
any considerable amount of light. Such rudimentary eyes may be 
found in most of the Sabetini, a tropical division of the Culicidæ, 
the wrigglers of which live in the small water spaces found in the 
leaves of Bromeliaceæ etc., where, probably, the supply of light 
is likewise very slight. Also these larvæ possess a very highly 
developed system of bristles. 
With regard to the respiration the larvæ of the Culicid-families 
may- be referred to four groups. 1. Larvæ which hang down from 
the surface by means of the sipho and, in this attitude, breath the 
air of the atmosphere; the majority of all Culicid-larvæ belong to 
this group. 2. Larvæ which take the air from the airchambers of 
submersed plants by means of different organs (sipho: Mansonia, 
antennæ: Aédeomyia). 3. Larvæ which live a pelagic life in the 
Water layers and mainly or exclusively breath dissolved air by 
means of the outer skin (Corethra, Mochlonyx). 4. Larvæ which 
Possess air-tubes but mainly live on or near the bottom of stagnant 
pools and are furnished with very large blood-gills. 
It is very .interesting to observe the extremely high degree of 
transformation of the different hair complexes of the Culicid-larvæ 
in accordance with the mode of life of the organism and the use 
it makes of the hairs. : 
Among those larvæ which hang down from the surface we find 
large bundles of bristles on the head, the thorax, and the abdomen. 
Their number, position, lenght etc. differ in the different species. 
Their principal importance is undoubtedly to augment that bulk of 
Water which belongs to the sensitive domain of the animal. The 
Significance of these hairs as outriggers contributing to support the 
larva in the water is probably very slight. In those larvæ which 
åre horinzontally supported by the surface-film (Anopheles) the 
dorsal bundles are peculiarly modified; they are transfigured into 
Palmated hairs arranged in two series on the dorsal side of the 
abdomen. Thus we find certain parts of the hair complexes ser- 
ving as a supporting apparatus keeping the animal to the surface- 
film. With regard to these larvæ it may be supposed, that the 
long thoracal and abdominal hairs may play a part as outriggers; 
