The President's Address. By Dr. C. T. Hudson. 7 
which are yet obscure, may serve to point out to students whither 
they can profitably direct their course : just as the lions and elephants, 
on the old charts of Africa, were the sign-boards which marked out 
the spots, where there was good entertainment for man and maps. 
Considering first the position which the class Kotifera holds in 
the Natural Kingdom, we find that it has been placed (apparently by 
common consent) in the limbo “ Incertas sedis ” ; so here at the 
outset we light upon a subject, that will give ample opportunity 
for research and study : for, while the humbler species of Botifera 
pass by easy gradations into larva-like worms, which have almost lost 
the characteristic ciliary wreath and trophi, the higher species have, 
standing at a great distance beyond them, a true rotiferon, Pedalion 
mirum, so far advanced in its structure that it forms an order by 
itself ; and, moreover, the gap between this order and the other three, 
which contain the rest of the 450 species of the Botifera , is obviously 
too great to be real. 
The forms, then, that link Pedalion to the others cannot be few ; 
and are, indeed, dimly foreshadowed by the hollow stumps of 
Asplanchna Ebbesbornii , and by similar processes in several of the 
male Asplanchnee. We have in the latter, as it were, the first rude 
sketch of a Pedalion ; for though their lateral processes do not end 
in swimming fans, and appear to be of no use to the animal, yet they 
have muscular fibres passing freely alQng their cavities from end to 
end. 
The male of A. intermedia has three such appendages, the female 
of A. Ebbesbornii has four, the male of A. Sieboldii has five, while 
that of A. Ebbesbornii has six. Increase the number of the muscular 
fibres, expand them into bands, attach them to the body- wall (as they 
pass the base of each process into the cavity of the trunk), and we 
shall then have limbs adapted for swimming, and wanting only 
the finish of the terminal fan to approximate to those of Pedalion. 
Indeed the female of A. Ebbesbornii looks just as if some species of 
Pedalion had had its limbs rounded off at the extremities, so as to rob 
them of their fans. 
On the other side of Pedalion, between it and the Arthropoda , 
there lies Schmarda’s Hexarthra which requires a special notice, as 
Eckstein and von Daday both consider the two animals to be identical. 
How they have come to such a conclusion I cannot imagine, unless 
they suppose that Schmarda had less power of observation than an ordi- 
nary child. For Pedalion is a conically shaped animal, with six limbs 
arranged all round the cone, parallel to its axis, and pointing 
from its base to its apex; how then is it possible for the merest 
tyro to draw those six limbs as radiating from a common base on the 
surface ? If a half-opened black umbrella had white pieces of tape 
sewn outside, along its ribs, could there be any one capable of 
declaring that the white tape formed a star, with six rays issuing from 
the middle point of one of the umbrella’s ribs ? And yet it is a 
