30 
their explorations are abruptly terminated by a sand- 
_ grain hurled adroitly, with almost unerring aim, by the 
hidden watcher below. They roll, surprised and 
stunned, to the bottom of the funnel, where a pair of 
fearful jaws are awaiting to receive them. . 
The magnification was now increased, and two 
series of objects were shown—‘‘ Pond Life” and 
‘Spider Faces.”” The former consisted of a number 
of well-known forms of the smaller inhabitants of 
ponds and ditches, the lantern slides being of course 
prepared from drawings. The ‘spider faces” 
apparently came somewhat as a surprise to the audi- 
ence, as nothing like them had been previously seen. 
Photographed in their natural colours and faithfully 
reproducing the most hideous expressions of mingled 
surprise, cunning, and brutality, their appearance was 
almost horrifying; and the more nervous members of 
the audience were by no means re-assured by the 
lecturer’s statement that several of the most ferocious 
of the spiders were very common in the Hampstead 
district. The final series of slides, might well have 
been termed a “rush” to the “ Infinitely Little,” 
for within the space of a few minutes, the audience 
were taken from the comprehensible to the incompre- 
hensible. A slide was shown of a filamentous marine 
alga (Polysiphoma fastigata) considerably magnified, 
and upon it was a small black spot. The magnifica- 
tion was then increased so that this spot filled the 
entire field of view, and under these conditions, the 
bacillus of anthrax was shown. A diatom (Licmophora) 
was exhibited during growth, and its minute size 
explained, the exquisitely marked siliceous skeletons 
of this and other members of the diatomacez, being 
then exhibited under increasing magnification. Aula- 
codiscus and Arachnoidiscus were enlarged to fill the 
entire field of view, and finally, a tiny fragment of a 
far smaller and delicately marked diatom (Pleurosigma 
