64 
PACIFIC SCIENCE, Vol. XXI, January 1967 
broad rostral spine; the lateral spines character- 
istic of later stages are absent. The large eyes 
are stalked. 
The first antenna (antennule) (Fig. 11) is 
conical and unsegmented, tapering distally to 
a blunt tip which bears 3 aesthetes and 2 hair- 
like setae. 
The protopodite of the second antenna (Fig. 
17) is produced into a strong lateral spine and 
bears a slender inner spine of approximately the 
same length. A small spine is situated ventrally 
at the base of the medial spine. 
The mandibles (Fig. 23) are armed with 
strong ventral teeth, short triangular teeth, and 
slender spines. The ventral tooth of the left 
mandible is split shallowly at the tip. There 
is little change except growth during zoeal 
development. 
The coxal endite of the first maxilla (maxil- 
lule) (Fig. 24) bears 3 terminal setae with 1 
small seta subterminally on the inner margin. 
The basal endite bears 2 strong curved spines 
armed with tiny spines, the small unsegmented 
endopodite bears a single long seta. 
The protopodite of the second maxilla (Fig. 
26) is triangular, bearing 3 setae on the blunt 
anterior margin, 1 set slightly apart toward the 
scaphognathite, and 1 small seta subterminally 
on the inner margin. In later stages, the anterior 
tip becomes more pointed and the 3 setae more 
evenly spaced (Fig. 27). The scaphognathite 
bears 7-8 plumose setae on the anterior-outer 
margin; one-third of the specimens dissected, 
from both hatching and plankton, had 7 setae. 
The short coxopodite of the first maxilliped 
(Fig. 29) is unarmed. The basipodite bears 7 
setae along the medial margin in groups of 
1—1— 2— 3 progressing distally. The endopodite 
is 4-segmented; the first three segments are 
armed along the inner margin as follows: first 
segment with a group of 3 setae, one conspicu- 
ously stronger than others and armed with tiny 
spines; second segment with 2 setae, again one 
being stout and armed with spinules; third seg- 
ment with 2 setae spaced around the distal mar- 
gin of the segment. The fourth segment bears 
4 terminal setae; the outer 2 setae are quite 
long and armed with spinules on the inner 
margin. There is also a short hairlike seta placed 
subterminally on the outer margin which fre- 
quently curves in between the terminal setae 
and is difficult to see without high magnifica- 
tion. The exopodite consists of 2 segments; the 
very short, often weakly delineated, terminal 
segment bears 4 long plumose natatory setae. 
The coxopodite of the second maxilliped 
(Fig. 28) is unarmed, the basipodite bears 3 
setae on the inner margin in groups of 1-2 
progressing distally. The endopodite consists of 
4 segments. Along the medial margin, the first 
segment bears 3 setae distally, the second seg- 
ment bears 1 seta, and the third segment has 
2 setae around the distal margin of the segment. 
The fourth segment bears 4 terminal setae and 
1 small subterminal seta on the outer margin as 
described for the first maxilliped. The exopodite 
is 2-segmented, the small terminal segment bears 
4 plumose natatory setae. 
The abdomen consists of 5 segments. The first 
is very weakly differentiated. The sixth segment 
is consolidated with the telson, as shown by 
the position of the uropods in subsequent stages. 
The telson (Fig. 34) is rounded, slightly 
concave, and usually about as wide as long, occa- 
sionally slightly longer than wide. There are 2 
prominent posterior-lateral spines notched near 
the tip on the outer margin. Between the lateral 
spines there are 25—27, usually 26, spines 
around the posterior margin of the telson, with 
a series of very small denticles between the 
spines. The eighth spine from either side is 
somewhat longer and more prominent than the 
remaining spines; all are armed near the base 
with small spinules. There is little change 
throughout zoeal development except for an 
increase in number of denticles between the 
terminal spines. 
In the following stages, unless noted, there 
is no change in setation and form of appendages 
described and figured for zoea I. 
zoea ii (Fig. 2): There is now a pair of 
short lateral spines on the carapace. 
The first antenna (Fig. 12) terminates with 
1 large aesthete and approximately 3 small 
hairlike setae. 
The second antenna (Fig. 18) bears a small 
subterminal spine on the medial margin of the 
lateral spine. 
The basal endite of the first maxilla (Fig. 
25), with the addition of 1 spine, now bears I 
3 strong curved spines armed with spinules; ; 
