442, FREDERICK KEEBLE. 
be exposed if they were deposited during the springs when 
the zone is laid bare at each tide and receives the full force 
of the incoming waves. 
Another noteworthy point is the rapidity with which the 
larvee hatch. Within 24—48 hours atter the capsules have 
been laid, the young emerge. ‘Thus the majority of C. para- 
doxa are, during the first few days of their existence, con- 
tinuously covered by water, and during this time also their 
habit of clinging to the weed is but ill-developed. Soon after 
the larvee emerge the yellow-brown cells appear and multiply 
rapidly in the body and the animals develop or acquire those 
tropisms whereby they maintain themselves, despite the 
recurring changes of tide and consequently of illumination, 
within the narrow limits of the Paradoxa zone. 
(d) The Eges and Larve.—The eges of C. paradoxa 
are laid in clutches contained in a common transparent 
capsule, each egg being likewise enveloped by a thin mem- 
brane (PI. 26, figs. 1, 2, 3). The common capsule is less 
mucilaginous than that of C. roscoffensis, but sticks very 
firmly to any object on which it is deposited. The number of 
eges in a capsule varies very considerably from as many as 
twenty-five to half or even less than half that number. By 
reason of the pigment of the eggs the capsules appear of an 
orange or pink-orange colour. The amount of pigment in the . 
egos varies very considerably. Its formation does not appear 
to be dependent on light, since eggs laid by animals kept for 
many days in darkness are as deeply pigmented as those 
produced by animals in normal situations.: The pigment 
consists of small oval or dumb-bell shaped granules, each of 
which presents the appearance of a double-contoured band of 
orange pigment with a clear inner part. ‘These pigment- 
bodies are probably the forerunners of the orange-pigmented 
olands of the adult animal. In addition to those granules 
which are distributed with fair uniformity, aggregations of 
finer granules of pigment may also occur in the egg. It was 
doubtless owing to the presence of the larger orange granules 
in the egg and larva that von Graff was led to the conclusion 
