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FASCICULI MALATENSES 
(2) When, on the other hand, the animal is resting on the bottom, the 
float takes on the appearance of a pair of slender processes, deeply grooved 
along their upper surface, which represents the anterior surface of the funnel, 
conjoined at their broadest point over the mouth and curling upwards, like a 
pair of horns, behind the eyes. 
As has been pointed out by Professor Max Weber, ^ who first described 
the tadpole, this change is brought about by muscular action, being due to a 
folding rather than a contraction of the structure, but Professor Weber’s 
explanation of its exact mechanism does not appear to me to be correct, and to 
clear this point from misconception areconsideration of the structure of the funnel 
in the light of the sectional method will be necessary. In discussing the 
funnel it will be convenient to speak of it as having a dorsal and a ventral 
wall, though these walls, as is readily demonstrated by a transverse section, 
are really quite continuous ; and each wall may be further regarded as having 
an anterior and a posterior surface, the latter being directed towards the 
bottom when the tadpole is floating, and the former applied to the surface 
film under the same conditions. 
Fig. I represents the outlines of a median longitudinal section of the 
funnel in its folded condition, and was obtained from a specimen preserved 
in 2-|- per cent, formol, which was later replaced by alcohol. It will be 
I. Ann. Jard. Bot. Buit%enzorg, 1898, Suppl. ii, pp. 1-5. 
