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PACIFIC SCIENCE, Vol. VII, January, 1953 
curved. Merus twice as long as broad; superi- 
or margin unarmed; inferior internal margin 
with tooth distally. 
Small chela of usual form in female, sub- 
spatulate in male. In female 3.4 times as long 
as broad, without sculpture; fingers slender, 
tapering, about as long as palm; short acute 
tooth at point of articulation of dactylus 
usually present, as illustrated, but sometimes 
reduced or completely absent. In male small 
chela relatively larger and heavier, 2.9 times 
as long as broad, without sculpturing except 
for slight depressed area on upper surface 
proximal to articulation of dactylus. Dactylus 
0.5 total length of chela, broad, flat, 2.7 times 
as long as broad, with dense fringe of setifer- 
ous bristles along margins, crossing top of 
article proximal to tip; tip compressed and 
hooked (dactylus balaeniceps-shaped). In 
both sexes carpus projecting over propodus 
as broad flat tooth, merus without tooth on 
inferior internal margin, otherwise similar to 
that of large chela. 
Carpal articles of second legs with ratio 
10 : 10 : 5 : 5 : 8. 
Ischium of third and fourth legs usually 
with movable spine; merus inermous; distal 
margin of carpus not produced into acute 
processes; propodus usually with about 10 
movable spines; dactylus simple, slightly 
curved. 
Largest specimen, female from Kaneohe 
Bay 26 mm. long; color usually transparent 
with reddish to greenish transverse bands. 
DISCUSSION: Marked variation was noted in 
C. crassmanus, as in several other Hawaiian 
species of which numerous specimens were 
collected. In this species the careful append- 
age-by-appendage study of size ratios was not 
made, but the following variations were noted. 
Antennular peduncles: The second article 
varies' in relative length from as long as the 
visible portion of the first and 1.5 times as 
long as the third to twice as long as the first 
and three times as long as the third. 
Large cheliped: The amount of sculpturing 
on this appendage varies markedly as is shown 
in Figure 49c, d, e, f. In some specimens, es- 
pecially the smaller ones, the sculpturing is 
very much reduced and noticeable only in the 
area adjacent to the margins; in larger speci- 
mens the shallow depression may be quite ex- 
tensive over both faces, usually with rounded 
and ill- defined margins but at times with def- 
inite limits. The tooth on the inferior internal 
margin of the merus of the cheliped is usually 
present although it is not as large as in many 
other species; however, in some specimens it 
may be reduced or entirely absent. In no speci- 
men seen was the upper groove other than 
gradually rounded on both margins. 
Small cheliped: In some of the larger females 
the dactylus, although it never approaches the 
extreme condition found in males, is often 
proximally broadened, not slender and taper- 
ing as in younger females. The tooth on the 
inner side of the articulation of the dactylus is 
almost always present, although sometimes re- 
duced; occasionally it is reduced to a rounded 
shoulder. No specimens were observed with 
a tooth on the merus like that of the large 
chela. No males were found without the ba- 
laeniceps-shaped dactylus. 
Second legs: The second article of the carpus 
varies from 0.75 to 1.3 times the length of the 
first, and the fifth article from 0.5 to 1.0 times 
the length of the first. 
It has been observed that those members of 
this species collected from Kaneohe Bay and 
especially those collected on the inner arms of 
Pearl Harbor, where the water is very warm, 
quiet, and filled with silt, are larger, averaging 
about twice the length of, and have a redder 
color than, specimens collected from coral 
boulders of the open reefs. No other charac- 
ters distinctive of the two groups of specimens 
could be found. 
The local specimens agree well with the 
original description of Heller, differing only 
in one possible point. Heller states, "Anten- 
narum spina externa basalis minima,” and, in 
his plate, does not show a spine at all, while 
in the Hawaiian specimens it is well formed. 
The ratio of the articles of the carpus of the 
