1902] MICROSCOPICAL JOURNAL. 19 
that did the Hydra and some Cladocera in fact, the sur- 
face film was a death-trap to rotifers. Rotifers provided 
with long spines, like Triarthra and many others, were 
at a disadvantage in that respect. Mr. A. A. Merlin’s 
paper “On the Spermatozoon of the Rat” was held over 
for the next meeting. Formal proceedings then termi- 
nated. At the conversazione many objects were exhibit- 
ed, including a model to show the support of the surface- 
film of water, exhibited by Mr. Scourfield. This was a 
piece of match weighted with a pin at one end sufficiently 
to make the match sink; the light end of the match was 
smeared with vaseline. On bringing the match from be- 
low to the surface of the water it hung supported from 
the ‘‘surface film.” Messrs. R. & J. Beck, Limited, ex- 
hibited a “Pathological” microscope with Mr. Ashe’s two- 
speed fine adjustment, and Mr. R. T. Lewis exhibited a 
slide showing the ‘‘Seuse-organ on the palpus of male 
Anopheles.” This was a curious projection on the ex- 
tremity of the palpus, free to move in all directions, even 
inwards. Itis not found on the common gnat, but is seen 
on the palpi of ticks. Colored drawings were also shown. 
Mr. Rousselet exhibited a slide of Lophopus crystallinus, 
beautifully mounted by himself, and Mr. Harland ex- 
hibited a slide showing trifurcate sponge spicules. 
MANCHESTER MICROSCUPICAL SociETY.—The monthly 
meeting of this Society was held on Thursday evening, 
November 7th, at the Grand Hotel, Manchester. Mr. 
- Mark L. Sykes, F. R. M.S., read a paper on ‘Evolution 
in Butterfly Scales.” Mr.Sykes said that he had selected 
for the purposes of his communication some of the speci- 
mens illustrated in his paper on ‘‘Natural Selection in the 
Lepidoptera,” published in the “Transactions” for 1897, 
as the illustrations would be available to the members, 
and would enable them to see the close resemblances 
which these butterflies bear to one another. In whatever 
direction the mimicry may tend, whether in simulation 
