NO. 8658 COPEPODS—CRESSEY 5 
Dorsal surface unornamented. Eye spots less obvious than in 
copepodid. Outer posterior corners of first free thoracic segment 
produced, extending nearly to end of second free thoracic segment. 
Genital segment as wide as long (1.4 x 1.4 mm), posterior corners 
produced to form short rounded lobes. Abdomen 2-segmented; each 
segment about same length but second segment somewhat wider than 
first and triangular (widest posteriorly). Caudal rami triangular; with 
four long terminal and two short subterminal plumose setae. Adhesion 
pad on ventral surface posterior to base of first antenna. 
First antenna (fig. 15) 2-segmented, similar to copepodid except 
that segments longer, bearing more setae. First maxilla (fig. 16) 
similar to copepodid except rugose process of copepodid is short 
pointed process in chalimus I. Second maxilla of chalimus I and all 
subsequent stages with plumose processes at base of two terminal 
spines (see Cressey, 1967a, fig. 129). Maxilliped (fig. 17) with pointed 
claw, seta on inner margin of claw. Legs 1-4 biramose. All rami 
2-segmented. Leg 1 exopod with four spines equal in length on outer 
terminal margin of second segment, endopod of first segment with 
adhesion pad on inner distal corner. Leg 2 exopod with four outer 
spines, distalmost about twice length of proximalmost spine. Leg 3 
exopod with four outer spines, proximalmost very small; other three 
becoming progressively longer, distalmost twice length of next longest. 
Leg 4 exopod with four spines, lengths as in leg 3. Leg 5 consisting of 
spine and two plumose setae at notch at posterior three-fourths of 
genital segment. Leg 6 a single spine near junction of abdomen and 
genital segment. 
Color in life: cream. 
CHALIMUS II, MALE.—Body form as in figure 18. Total length 8.6 
mm, greatest width 4.6 mm (all measurements based on single speci- 
men). Clear fringe around cephalon and outer corners of first free 
segment (not seen in previous stage). Principle changes in body form 
from previous stage are proportionately wider cephalon, elongation of 
genital segment, and more prominent caudal rami. Adhesion pads 
present ventrally on cephalon, one posterior to base of first antenna 
and a small one on basal segment of second antenna. 
First antenna (fig. 19) with both segments longer and with in- 
creased ornamentation over previous stage. Second antenna (fig. 20) 
with well-developed claw; bearing two short setae, one at base of 
claw and one median. Maxilliped (fig. 21) with well-developed claw. 
Other head appendages as in previous stage. 
Legs 1-4 biramose (see pls. 1-4). Spine and seta formula for legs 
1-4 of last three immature stages and adult male are as follows (Ro- 
man numerals refer to spines, arabic to setae) : 
