BRIGHTWELL, ON NOCTILUC^. 
189 
multiplied by self-division^ two and sometimes three indi- 
viduals adhering by the outer edge only. (See ' Fauna In- 
fusoria/ p. 21.) Eichhorn is also stated to have seen self- 
division in A. Sol ; and the question may^ we think^ be con- 
sidered as put to rest by Mr. Weston^ y^ho has^ from his own 
repeated observations^ written down self-division in A. Sol 
as a fact. (See ^ Micr. Journ./ vol. iv^, p. 120.) 
The facts now brought to light relative to the Noctilucse^ 
tend^ we apprehend^ to show that they must take their place 
in the lower rank of organized beings^ and that they have 
some affinity with Actinophrys Sol, though by no means 
congeners with it. 
Before completing the plate illustrating this article^ Mr. 
Tuffen West went down to Gorlestone to make some addi- 
tional drawings from living specimens^ and he has also fur- 
nished me with some notes,, the result of his observations^ 
which I have great pleasure in adding to this paper. 
^' Slight movements of the Noctilucse cause them to vary so 
much in their apparent form^ that it is difficult to obtain an 
exact idea of their true figure. By turning the live box in 
which specimens are contained upside down occasionally^ 
and watching them as in their progress to the surface they 
roll over and over^ a good idea of these changes of appear- 
ance may be obtained. A pyriform or balloon shape is 
thus frequently seen^ at the smaller end of which is the 
fissure described by previous observers^ and near to it the 
mouth with the root of the tail^ &c. We term this ' the side- 
vieiv' (see fig. 2) . The so-called ' tooth/ or rather ^pre- 
hensile organ/ in some cases presents exactly the appearance 
figured by Mr. Webb ; in others that given by Mr. Huxley 
(^ Micr. Journ./ vol. iii^ PI. fig. 34 d) . It appears to 
be formed by a duplicature of the general integument^ from 
which it differs little in density or appearance. I did not see 
it in independent motion^ but repeatedly moved in connection 
with the movements of the tail. 
c( rpj^g c cilium^ once seen can hardly fail to be again 
instantly detected ; its action is intermittent ; periods of rest 
of a second or two being followed by rapid undulatory move- 
ments for eight or ten seconds. Its motion is probably sub- 
servient to respiration, and is to be classed with the ^ trem- 
bling organs^ so lucidl}^ described by Professor Huxley in 
Lacinularia (^ Trans. Micr. Soc./ vol. i, n. s., p. 7), and sub- 
sequently in Echinococcus. The sarcode fibrils constantly, 
though slowly, change their form and position. I once saw 
two processes move rapidly out from near the nucleus, 
