132 ON THE DEVELOPMENT OF 
mentary, but capable of producing its several parts. During 
the period that these short rounded branches exist, and before 
they have begun to assume the polype-character, a young Pyc- 
nogon enters one of them, having made a journey from the 
polype by which it entered, along the ccenosareal tube of the 
Coryne; arrived at the end, there it remains to mature, and, by 
a wonderful provision, the development of the terminal portion 
of the polypary into a polype is stayed (Pl. VL., figs. 7, 8), 
doubtless by the young Pycnogon availing itself of the nutrient 
matter circulating within the ccenosare as food, and thus with- 
drawing the material that should have developed a polype. The 
outer envelope or portion of the polypary (at this particular part) 
gradually enlarges, so as to assume the form and appearance be- 
fore described, and the Pycnogon being comfortably housed amidst 
an abundant supply of food, nothing but time is requisite to en- 
able it to undergo the necessary development. 
With such an abundant supply of food as must necessarily be 
presented to the young parasite within the Coryne, its growth 
must be rapid. At Pl. VL. fig. 10, I have represented one of the 
animals extracted from the sac. At this stage its size is much 
greater than the minute form before described: it now measures 
zs inch across. An inspection of the figure will convey a pretty 
accurate idea of the appearance of the animal. It will be seen 
that the foot-jaws still retain their advanced state of develop- 
ment, as compared with the other portions, and the rostrum is 
still short and rudimentary. The foot-jaws were very active, 
opening and shutting ina highly excited manner, which was, 
perhaps, not to be wondered at, when we consider the unceremo- 
nious way, in which it was again introduced into the world. 
Within the rostrum, near its base, a peculiar pulsating movement 
is seen; further than this, no motion is discernible. 
The larva must have moulted, and got rid of the four rudi- 
mentary legs, and their filamentous appendages; for we here see, 
that the young Pycnogon is destitute of legs (not a trace remains), 
and that the previously described procéss of the production of 
these organs by the gradual formation of lobes, to be subsequently 
elongated into legs, is again seen: there are now seven such lobes, 
