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OBSERVATIONS ON LIVING SPECIMENS. 
OBSERVATIONS ON LIVING SPECIMENS. 
MOVEMENT. 
Specimens belonging to several families were kept under observa- 
tion at different times. It was found in all cases, where no injury 
to the animal had taken place, that pseudopodia were thrust out 
within 5 minutes of the time of contraction. This was true of 
Tridia and Haliphysema in the Astrorhizide, Discorbis in the 
Rotaliide, Polystomella in the Nummulitide, and Quinqueloculina, 
Orbiculina, and Orbitolites in the Miliolide. 
One observation of much significance, in view of the widespread 
view that individuals of various species or even genera may unite, 
seems to entirely disprove this theory. In all cases where specimens 
of the same species even were brought near enough to have their 
pseudopodia touch there was a repellant rather than an attractive 
action. The same was true of specimens of different species and 
those of different genera. While specimens were under observation, 
they occasionally altered their course abruptly. In such cases it 
was often found that the pseudopodia of the specimen under observa- 
tion had come into contact with those of another. In all such cases 
the first specimen changed its direction, usually rotated the test 
somewhat, and started off in a new course, often 90° from that in 
which it was at first traveling. 
Portions of the same specimen, however, when separated by 
cutting, threw out pseudopodia rapidly, and when those of one 
part touched those of the other they quickly anastomosed and the 
two masses moved toward one another and coalesced. 
The rate of movement of the protoplasm in the pseudopodia was 
recorded in Iridia diaphana and Orbitolites duplex. The unit of 
measurement in all experiments was 10 units of the micrometer 
scale, which on the slide represented about 0.2 mm. As in the 
movement of the whole test, there is apparently a rhythmic move- 
ment instead of a constant one. In one specimen of Jridia diaphana 
the movement along the more slender pseudopodia was as follows 
for the return current—the rate in seconds for the 0.2 mm. 
8, 8, 8, 9.6, 7.5, 10.2, 8 seconds. 
The average of movement in the slender pseudopodia was about 40 
seconds per millimeter. In large coalesced pseudopodia it was 
slower, averaging about 60 seconds per millimeter. 
One group of records shows the rhythmic character in 10 suc- 
cessive units of 0.2 mm. each: 
10, 8, 7.8, 8.4, 9.2, 10, 9.4, 9, 8.2 seconds. 
A series of measurements of the pseudopodia in Orbitolites duplex 
gave the following for 0.2 mm. units: 
12.8, 8.8, 9.2, 14, 12, 7.8 seconds. 
