THOMPSON: METAMORPHOSES OF HERMIT CRAB. 
165 
opening and presents four diverticula: anterior, lateral, dorsal, and 
posterior lobes. The cells of these glands are vacuolated and 
distended by deposits of a highly refractive yellow substance that 
stains black with osrnic acid. As in the adult, cells or groups of 
cells may partly occlude the lumen, and during the fourth zoea and 
glaucotkoe stages this phenomenon reaches its climax (pi. 9, fig. 58). 
The lateral caeca at this time are rounded glands which resemble 
the livers in histolog}^ and in reactions to reagents. Posteriorly they 
become approximated and enter the main canal dorso-laterally at 
the origin of the intestine, ten or even twenty micra cephalad from 
the openings of the livers (pi. 9, figs. 48, 49, 50). 
The livers and lateral caeca of the glaucothoe have at first the 
same relations as in the zoeae except that they extend within the 
newly developed thorax (pi. 8, fig. 38). The lateral caeca are 
insignificant in size throughout the phase, and undergo no meta¬ 
morphosis beyond a separation of their proximal ends, so that they 
enter the intestine at the sides of the stomach, as in the adult crab. 
The livers, on the other hand, pass through a complicated meta¬ 
morphosis. 
A description of a selected series of glaucothoe of different ages 
will better indicate the order of these modifications as well as the 
relations that they bear to the changes in position or structure in the 
other organs of the body, than a detailed account. The altera¬ 
tions are of course, subject to slight individual variations. 
1. A young glaucothoe just moulted from the zoea (pi. 8, fig. 
38). Only the posterior lobes of the livers have increased propor¬ 
tionally to the increased size of the stomach. 
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2. An older specimen, never in a shell (pi. 8, fig. 39). The 
anterior and dorsal lobes of the livers are further reduced; the 
lateral lobes have almost disappeared, though the one on the right 
1 still retains a minute lumen ; the posterior lobes extend to the last 
segment of the thorax and the apex of the right gland lies beneath 
the intestine toward the left side of the body. The openings of the 
lateral caeca into the intestine are now caudad instead of cephalad 
from the openings of the livers. The green glands have begun to 
grow back to form the median neplirosac and a new artery is 
developing in the abdomen. 
3. A still older specimen. The lateral liver lobes have disap¬ 
peared ; the dorsal become mere prominences, and the posterior 
barely enter the abdomen. 
