Hawaiian Crangonidae — BANNER 
141 
est in the present collection, unfortunately is 
somewhat smaller (32 mm.), and was collected 
on Maui near where Dana had collected other 
Hawaiian types (see under C diadema and C 
pugnax) . It agrees well with Dana’s description 
and plates except in the ratio of the articles of 
the carpus of the second leg which according 
to his plate had a ratio of 10 : 5 : 3 : 2.5 : 4, 
which is 10 : 8 : 3 : 3 : 5.5 in this specimen. 
While this character was quite variable in the 
specimens in the present collection, in no case 
did it approach the extreme given by Dana; 
however, it is likely that this difference still 
can be individual variation or possibly a 
growth difference. A second more slight dif- 
ference is that Dana’s plates do not show the 
proximal margin of the superior groove of the 
large chela overhanging the groove; this char- 
acter, too, is somewhat variable in these speci- 
mens, and may well be either an individual or 
a growth difference. 
This species resembles C crassimanus (Hel- 
ler) very much, and there is no positive way to 
distinguish between them except by the char- 
acter of the first thoracic legs. The small chela 
in the male is subspatulate in C crassimanus 
and of the usual form in both the male and 
female in C. pacifica. On the large chela the 
most useful character is the presence of a 
tooth on the internal distal angle of the merus 
in C. crassimanus, with none in C. pacifica; 
however, this tooth is variable in size and 
often very much reduced. The proximal edge 
of the upper depression is rounded in C. cras- 
simanus and usually overhangs in C. pacifica, 
but some specimens of both species approach 
the perpendicular. The superior depression on 
the internal face usually extends posteriorly 
past the mid-line of the palm in C. crassimanus 
and scarcely back of the upper edge of the de- 
pression in C pacifica. 
distribution: This species, like C. crassi- 
manus, is common in shallow waters. It does 
not seem to penetrate the inshore portions of 
the reefs nor the quieter waters of enclosed 
bays as much as C. crassimanus (although it 
does penetrate as far into Kaneohe Bay) ; it also 
reaches a bit further beyond the tidal zone 
having been collected from water l5 feet deep 
at Nanakuli, Oahu. It has been collected from 
the following localities on Oahu: Kaneohe 
Bay, Waimanalo, Hanauma Bay, Black Point, 
Waikiki, Nanakuli, Mokuleia, Kawela Bay, 
and Kahana Bay; on Maui it has been col- 
lected at Makena, Kalama Park, Lahaina, and 
12 miles south and 10 miles north of Lahaina. 
The ’’Albatross” collected specimens on Ho- 
nolulu Reef and at Waialua, Oahu (U.S.N.M. 
63590 and 63593) and Napili Harbor Reef, 
Maui (Station No. 3881, U.S.N.M. 63592). 
Edmondson (1925) has reported the species 
from Laysan and Ocean Islands. 
It is widely spread through the Indo-Pacific 
region, from the Red Sea and Madagascar to 
New South Wales and Wake Island. 
Species of Doubtful Record 
Crangon strenua (Dana) 
AlphcnS strenuus Dana, U. S. Explor. Exped. 
13(1): 543, pk 34, fig. 4, 1852. 
Originally described from Tongatabu, 
Tonga, this species is of wide distribution in 
the south Indo-Pacific, from the Galapagos 
on the east to Djibouti at the mouth of the 
Red Sea on the west. It was reported from an 
unspecified locality in Hawaii by Stimpson 
(1861) as A. avarus Fabr. (he regarded A. 
strenuus as a synonym for A. avarus). How- 
ever, as the species has not been reported 
from this archipelago since that time, and as 
it can be confused most easily with the com- 
mon C. crassimanus (Heller) (the two species 
can be separated with certainty by the pres- 
ence of a balaeniceps-shaped small chela in 
both the male and female in C. strenua in 
contrast to having the condition only in the 
male in C. crassimanus), it is likely that Stimp- 
son made a mistake in identification. 
