1901} MICROSCOPICAL JOURNAL. . 303 
Notes on Microscopy. 
F. SHILLINGTON SCALES, F. R. M. S. 
AND H. A. HAIG. 
CoLoRING OF WATER BY Micro-ORGANISMS.—Much cur1- 
osity and speculation have been aroused in the neighbor- 
hood of Stoke Bridge, Ipswich, by the turbidity and deep 
chocolate color of the river Orwell, reaching for some lit- 
tle distance from each side of the bridge. This appear- 
ance has been ascribed by some to the scourings of the 
maltings, by others to spawn, also to the sun, or to the 
remains of star and jelly fish. This remarkable color- 
ation of the river is in streaks of a greater or less width, 
and extends but a few inches beneath the surface, whilst 
on the decline of the sun the color wholly disappears. 
This phenomenon is caused by countless myriads of beau- 
tifully marked plants of a deep chocolate shade. This 
coloring matter can readily be discharged by chemical 
reagents and the green structure of the plant rendered 
apparent, or by the action of iodine the presence of starch 
can readily be determined. ‘These plants bear a striking 
similarity in their movements and power of contractility 
to the fresh water Euglena, but in form they resemble a 
bicuspid tooth, with a deep cleft on each side of the axis. 
‘The two fangs might be taken to represent the head, and 
the crown the base; each plant being about the 1-3,000th 
of an inch in diameter. Some hundreds of these organ- 
isms may be seen gaily disporting themselves in a drop 
of water scarcely exceeding in size a pin’s head, the whole 
being in a rapid state of motion. These brackish water 
organisms are delicate, breaking up a few hours after be- 
ing removed from their habitat. The plants appear to 
come up with the tide, and are not due to the presence of 
sewage or other preventable matter.—Alfred Martinelli, 
Ipswich. 
BRAct AND FRUIT-SCALE IN CONIFERAE.—The carpellary- 
