FISH PHOTOGRAPHY AT HOME _ 189 
one. The difficulty, however, consists in the fact that 
with the less elaborate apparatus a great deal of dodging 
and manipulation is required, which necessitates assist- 
ance. In order to facilitate photography of larval fishes, 
on my return from Port Erin I constructed an appara- 
tus by means of which it is possible single-handed 
to take a photograph of living objects in a vertical 
or horizontal position by daylight or by artificial 
illumination. Further, the object can be photo- 
graphed life-size (provided it is not more than five 
inches in length), or any part of it up to a magnifica- 
tion of 2,700. 
The aim I had in view when constructing this appar- 
atus was that an expert biologist should be able to 
put an object in a certain position upon the stage, 
and that any ordinary photographer should be able 
to photograph it at any given magnification by 
transmitted or reflected light, night or day, without 
touching it. 
I have illustrated the photographer at work with this 
apparatus in the horizontal position taking a photograph 
of a larval fish. The movements of the young fish in 
the live cell are watched on the mirror of this reflex 
micro-photographic camera. With the right hand the 
object is kept in sharp focus all the time by turning a 
screw which is connected with the microscope. As soon 
as the larval fish is in the desired position, an exposure 
is made by releasing the focal plane shutter with the 
bulb in the left hand. 
