106 Tue Microscope. 
The measurements of my specimens closely correspond 
with those of the English; much more closely indeed than is 
usually the case, according to my experience, with American 
infusoria that are otherwise undoubtedly identical with the 
European. The body is about sooo inch long, obovate or sub-— 
spherical, the flagellum nearly seven times as long, and the collar 
about +755 inch in height. The pedicle is rather shorter than 
the measurement (4405 inch) given by Mr. Oxley, but it is con- 
spicuously developed. 
Reproductive fission takes place rapidly, and the colonies 
consequently increase speedily in numbers and size. On the 
evening of the day when the gathering was made, two large 
clusters were captured at the first plunge of the dipping tube; 
two days later the number had apparently doubled. 
The observer will not soon forget his first glimpse of a large 
colony of these colorless creatures apparently floating side by 
side but widely and evenly separated by an investing invisible 
something, the wondrously long flagella lashing the water, the 
conical collars erect and expanded, and the two little posterior 
contractile vacuoles alternately snapping themselves out of 
sight; and although I have nothing new to add to Mr. Oxley’s 
observations, I record the first capture of the species in this 
conntry as an interesting occurrence of a European form far 
from the habitat in which it was originally discovered. 
THE MICROSCOPE AND THE TELESCOPE. 
A FRIEND wrote us asking “* What is the difference between 
the microscope and the telescope.” We asked Prof. M. W. 
Harrington, of the Astronomical Observatory, to answer the 
question for us, which he does as follows: 
“These two instruments, constructed on identical physical 
principles, differ in their details because of the relative position 
of the object viewed. In the microscope the object is very 
near, in the telescope very far; in the first the rays of light 
utilized are very devergent, in the second the rays are practi- 
cally parallel. Perhaps the simplest view of the telescope is 
that it is a microscope reversed. In the telescope the eye is at 
the small end where the most of the magnifying is done; in the 
s 
