This appearance is diagnostic of the Anopheline 
larva. One species ( M . turkhudi ) does not, however, 
rest in this position, but after rising to the surface in 
a horizontal position slowly sinks until the tail only 
touches the surface. 
Anopheline larvae, which are about to turn into 
nymphae, also sometimes tend to sink, so that the 
head is directed obliquely downwards (often seen in 
M. rossi). 
One species at least of Culex (C. concolor ) adopts 
a nearly horizontal attitude. The line of indentations 
of the surface film mentioned above, is not however 
seen. 
2. When disturbed, Anopheline larvae dart into 
the water, or what is very characteristic, if not greatly 
disturbed, they pass by a series of wriggling jerks along 
the surface of the water. 
When moving up towards the surface, an 
Anopheline moves in a much more irregular and jerky 
manner than a Culicine larva. 
3. Anopheline larvae, when full grown, possess 
very small heads in proportion to the size of the larvae 
(about eight mm. in length). In most of the Culicinae 
the head is very large, with very prominent and large 
antennae. 
4. Anopheline larvae have no syphon, the tracheae 
opening into a pit on the dorsum of the eighth 
abdominal segment. 
Procure a considerable number of Anopheline 
larvae, and ascertain the following points :— 
1. The Moulting of Anophelines. —Note that as 
Anopheline larvae grow in size they cast their skins. 
Remove a cast skin by floating it upon a slide. Note 
the perfect nature of the £ skin,’ and how all the 
chitinous structures are represented, even air tubes. 
