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PACIFIC SCIENCE, Vol. XXI, October 1967 
unchanged from the previous stage except that 
it is more elongate and now may have either 
1 or 2 pairs of submarginal setae. The medial 
telson process may be replaced by a pair of 
articulated processes. In series where the fourth 
zoeal instar was followed by another zoeal 
stage, the appendages were less well developed 
and the resulting fifth stage zoea did not differ 
significantly from the advanced fourth stage 
here described. The following remarks are 
based on specimens which moulted directly 
to glaucothoe from this stage. 
Terminal Zoea 
CARAPACE length: 2. 4-2. 9 mm (9 speci- 
mens) 
total length: 5. 5-6. 2 mm (8 specimens) 
The antennule shows subterminal groups of 
aesthetascs on the dorsal flagellum, and the lobe 
which will become the ventral flagellum is well 
marked and may have a terminal seta. There 
are 3 or 4 large plumose setae proximal to the 
distal articulation of the peduncle. 
The antennal scale may have 13-15 plumose 
setae on the medial margin. The endopodite 
may now reach as far as the base of the 
terminal spine of the scale, is still terminated 
with a single process, but consists of at least 
2 or 3 segments with one or more distinct 
articulations. 
The mandibles are still more complex and 
show buds of the palps. 
The maxillule has added 2 strong teeth on 
the basal endite, and usually 1 or 2 setae on 
the coxal endite. 
A naked proximal lobe is present on the 
scaphognathite of the maxilla and as many as 
22 plumose setae may be on the margin of 
the scaphognathite. The proximal lobe of the 
coxal endite of the maxilla has also increased 
in setation. 
The first maxilliped usually carries 7, some- 
times 6 or 8, natatory setae on the exopodite. 
The proximal medial corner of the basipodite 
may be rather prominently produced, with the 
usual pair of setae often reduced to a single 
seta. 
The second maxilliped may have 7 or 8 
natatory setae on the exopodite but is other- 
wise unchanged. 
The third maxilliped has 7 or 8 (rarely 6) 
natatory setae on the exopodite. The endopodite 
is very well developed, segmented, and bears 
a total of 1-5 setae on the terminal segments. 
The pereiopods are well developed buds. The 
pleopods are represented by unarmed buds on 
abdominal somites 2-5. 
Glaucothoe 
SHIELD LENGTH: 0.9 mm (3 specimens) 
CARAPACE length: 1.3-1 .4 mm (2 speci- 
mens) 
TOTAL LENGTH: 3. 8-4.0 mm (3 specimens) 
The post-zoeal stage in hermit crabs, as in 
all reptant decapods, is radically changed from 
the last zoeal stage: the long rostrum has dis- 
appeared, the carapace of the glaucothoe being 
almost the form of the juvenile, the pereiopods 
are free and functional, the pleopods are setose, 
the telson and all the cephalothoracic appen- 
dages have undergone radical change. The il- 
lustrations show how the gross external mor- 
phology of the glaucothoe of T. magni ficus 
differs from the zoeal stages which preceded it. 
As in all other described glaucothoes of the 
family Diogenidae, except that of Diogenes 
pugilator, there are no ocular scales at the 
bases of the eyestalks. In three specimens 
checked, the setation of the pleopods varied 
from 8-10 per pleopod, with no consistency in 
pairs or by somite. Other morphological fea- 
tures of particular significance are shown in 
the illustrations and will be discussed below. 
The abdomen of the glaucothoe bears a few 
prominent chromatophores. In lateral view 
there is one red chromatophore anterior to the 
pleopods of the fourth abdominal somite. On 
the fifth abdominal somite there are two lateral 
and three ventral red chromatophores. Each of 
the protopods of the uropods, attached to the 
sixth abdominal somite, bears one red chro- 
matophore. In dorsal view the fifth abdominal 
somite shows a pair of chromatophores on the 
anterior border and a pair on the posterior 
dorsal margin. The telson bears a pair dorsally 
and two pairs ventrally. Other chromatophores 
may be present, but only those mentioned 
above were noted in a brief examination of a 
living specimen. Diffuse orange color was seen 
under the eyestalks and in the region of the 
mouth, but the precise location of the origin 
of the pigment was not determined. 
