Life History of Monads. By W. H. Ballinger f J. Drysdale. 191 
arises from the complete flexibility of the flagella, by which a 
propelling motion plainly could not be applied. 
We now proceed to the description of the form immediately 
before us. For working purposes we have called it the “ calycine.” 
Its general appearance is accurately shown in Fig. 2. Its length 
varies from the -^oth to the yoVoth of an inch, its breadth in the 
broad part being a little more than a third of this ; but it is com- 
pressed from side to side, and its width edgewise is not more than 
an eighth of its length. The form as shown in the drawing is very 
regularly preserved. The front of the body-sarcode is obliquely 
flattened, and at its lower part this gives rise to four flagella. 
They take their origin in a stalk which is short and almost at the 
point of contact with the body-sarcode divides into four pyramidal 
parts, out of which the flagella come. Just under the place where 
the flagella originate, at the flattened end of the sarcode, a spout- 
like projection occurs, as at a, Fig. 2. A long furrow goes obliquely 
down from this spout towards the pointed tail at the opposite end ; 
and another depression occurs in the middle of the form, also length- 
wise, giving the hourglass shape to the flattened extremity b. The 
sarcode is at times loose in texture, and the monad takes as a con- 
sequence unusual shapes, one of them being remarkably like a 
Brazil nut, and others still more distorted. The flagella are ex- 
tremely fine, and are so rapid in their movement that their number 
was only certainly made out after nearly a week of watching ; but 
as the forms became more inert we were enabled to discover their 
number accurately. A large nuclear body was always present in 
about the same position — c, Fig. 2— and two large “eye spots,” 
with the strange rhythmical opening and shutting to which we have 
referred in other monads.* The position and relative size of these 
are shown at e ; the diametrical line in each disk is the line of junc- 
ture, and from this both halves opened and then closed again with 
a snap. Its mode of locomotion was a graceful gliding through the 
water, the flagella moving so often and so rapidly as to render their 
detection impossible when the monad is at its swiftest. They could 
roll over on their long axis, and change the direction of their motion 
with lightning-like rapidity, and however crowded the field, not 
the slightest approximation to collision occurred. 
A number of vacuoles are sometimes scattered over the sarcode, 
and at times the body becomes distinctly granular, the sarcode being 
slightly distended ; and we have seen this granular matter quickly 
discharged, the body being left transparent and retracted. From 
the analogy of the “ biflagellate ” we were led to presume that this 
was one of the developmental phases, but the presumption was not 
confirmed by observation, and we simply record the fact. 
The first process in the life history of this monad is, as usual, 
* ‘M. M. J.,’ vol. x., p. 248; also vols. xi. and xii. 
