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sipho of the mosquito larva to the piercing organ of Mansonia 
by a mere prolongation of the felt covered part by e2, i. e. the 
respiratory cup of the common mosquito larva in connection with 
the closing apparatus of the sipho; the cup -is used by Mansonia 
as the proper piercing organ which in a telescope-like manner is 
inserted into the outer tube, built up of the 5 flaps of the closing 
apparatus; the walls of the piercing tube are strengthened by pieces 
usually not found in the mosquito larvæ. 
It now remains to demonstrate the piercing action of the. appa- 
ratus. When a larva is going to fix itself on a plant, it will go 
down into the thick texture of stalks, submersed leaves, roots etc. 
covering the bottom in most of our shallow ponds and smaller 
Jlakes. Where the, vegetation is so dense that the larva may be 
steadied in all directions by means of its bristles, it will first try 
to bring its longitudinal axis parallel to a little green, living twig; 
then it makes some vigorous strokes with the tail and creeps 
backwards along the twig. By means of the binocular microscope 
it is possible to observe the points of the bunches of bristles on 
the back all acting as supporting points in relation to the twigs; 
simultaneously the sipho wrings in all directions, and the two long, 
curved bristles (c) above the sipho move upwards and downwards, 
the bristles acting as legs. The animal, secured in all directions 
by means of the bristles, climbs 'upwards. 
Then the larva stop climbing. The sipho is now going to be 
used as a piercing organ, and is consequently dirigated vertically 
towards the twig; the two bristles are pressed into the tissue, and 
the anal segment is going to functionate. The large swimming-fan 
is moved to and fro, regularly as a clock-work; while the point 
of the sipho with the piercing teeth is pressed against the twigS 
the motion of the anal segment drives the point into the tissue. 
If the reader will throw a glance upon the microphoto (fig. 4) and ima- 
gine himself the above mentioned motion of the tail, and remember 
that the point of the sipho is pressed hard against the plant, he 
will understand, that by this motion combined with the action of the 
teeth on the apex the tube must be forced through the epidermis 
of the plant. The only condition still remaining is the possession 
of organs for transmission of power from the tail to the sipho. 
We will return to this point later on. We are now able to under- 
