34 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 120 
MALE RIGHT ANTENNULE.—In the penultimate male the right Al is 
similar in morphs 1 and 2 (fig. 77). This appendage is distinguished 
from that in jollae and kolpos by the presence of a prominent spur 
extending distad on the sixth from the last segment. Based on 
clusters of two-three setae and intersegmental sutures, the terminal 
segment represents fused segments 24 and 25 in the adult, and the 
spur emanates from segment 19. The process on segment 19 extends 
distad overlapping segment 20. In the adult stage segment 19 is 
fused with segments 20 and 21, the fused unit bearing a denticulated 
ridge (friction plate). It would appear that the spur on segment 19 
in the penultimate stage is the precursor of the denticulated ridge in 
the adult. A similar spur has been observed in stage V males of the 
mirabilis group found in the Gulf of Mexico, Bahamas Islands region 
(Fleminger and Tan, 1966). 
In the stage V copepodite there is no indication of bimodality in the 
length of segment 18 (fig. 15). The mean length of segment 18 is 
0.1360 mm in morph 1 and 0.1358 mm in morph 2; the difference is 
not significant. The proximal extension of the denticulated ridge on 
segment 18, or its precursor, is not present prior to stage VI (fig. 77). 
RELATIONSHIP BETWEEN STAGE V AND STAGE VI MALES 
Both stage V and stage VI males are dimorphic; i.e., each is bimodal 
in some morphological aspect and one or more of the involved struc- 
tures differ discontinuously and are nonoverlapping. In stage V, 
morph 1 differs from morph 2 in the length of the right P5 exopod, 
the anlage of the chela. Also, the mean TL of morph 1 is slightly 
larger than that of morph 2. In stage VI, morph A differs from 
morph B in details of the right Al, the size and shape of the chela, 
and in the mean TL being slightly larger than that of morph B. In 
the right Al, segment 18 does not exhibit bimodality prior to stage 
VI (fig. 15). Pursuing the chela relationships one more step, the 
longer, slenderer exopod of right P5 in morph 1 would be expected to 
produce the larger, slenderer chela of morph A, while the shorter, 
stockier right P5 exopod of morph 2 is more likely to yield the smaller, 
stocky chela of morph B (fig. 14). Other things being equal, these 
parallel relationships and size similarities (table 8) provide a reason- 
able basis for postulating that at maturity morph 1 yields morph A 
adults and morph 2 produces morph B adults. 
There is no obvious agreement in the relative abundance of the 
morphs between stages V and VI (table 9). The ratio of stage V 
and stage VI morphs vary widely in individual samples and in the 
summed totals as well. This may not constitute a denial of the 
postulated relationship of the four morphs since genetic polymorphism 
provides the species with a rapid process for resolving adaptation 
