424 
PACIFIC SCIENCE, Vol. VII, October, 1953 
somite armed with numerous long spines, 
each ending in a blunt, rounded tip from 
which protrudes a soft fleshy process. Arti- 
culation between telson and preceding seg- 
ment barely discernible dorsally. Telson cov- 
ered with series of 22 regularly arranged spines 
similar to those of preceding segment; distal 
margin composed of four spine-like processes 
bearing secondary spines on outer edges, two 
submedian with single row of secondary 
spines, two intermediate with single inner 
row of secondary spines and double row of 
secondary spines along outer border (Fig. 20). 
Exopod of uropods with eight movable spines 
on outer margin; endopod with five spines 
on dorsal surface; elongated basal portion of 
uropods with two spines, outer longer than 
the inner. Endopod of first abdominal ap- 
pendage of male shown in Figure 21/. Spec- 
imens, when alive, are a brilliant red or orange. 
Specimens preserved in alcohol immediately 
turn a mottled yellow or tan, but those pre- 
served in formaldehyde have retained their 
red color after several months. Specimens 
range in size from 28.5 to nearly 70 mm. from 
the tip of the rostrum to the distal margin of 
the telson. 
DISCUSSION: This is the only species of this 
world-wide genus which has been reported 
from the Hawaiian Islands. The type spec- 
imen was taken by H.M.S. "Herald” at Fiji 
Islands. Miers (1880) reported this to be a 
female, but Kemp (1913) stated that it was 
a male; apparently Kemp was the one who 
made the error in identification. Another fe- 
male was taken at Honolulu by H.M.S. "Chal- 
lenger,” but Brooks (1886) put it in the genus 
Protosquilla. The only other record of the spe- 
cies is a single male specimen in the Bishop 
Museum which was taken off Waikiki, Oahu. 
In the spring of 1949 two males and four 
females were dredged off Waianae, Oahu, in 
water 50-120 fathoms deep. This appears to 
be the greatest number of specimens collected 
at any one time. 
This species is easily recognized by the 
radiating series of spines found on the telson 
and the last two abdominal somites. The 
rectangular carapace with its trispinous ros- 
trum is found in several species of this genus. 
GomdactylusMiAlx.^ related genus, Odontodac- 
tylus, are very similar with regard to the ischio- 
meral articulation and the inflated base of the 
raptorial dactylus (Fig. 21c); however, Gono- 
dactylus is distinguished by the absence of 
spines on the raptorial dactylus, which may 
be entirely smooth or serrated on its inner 
margin (Fig. 21c). Odontodactylus, on the other 
hand, has several spines on the inner margin 
of the raptorial dactylus. 
Brooks (1886) placed this and several allied 
species in a new genus, Protosquilla, because 
the telson and sixth abdominal somite, al- 
though separate, were nearly fused. He also 
stated that the small size of the antennary 
scales and uropods and the trispinous ros- 
trum were sufficiently distinct to warrant the 
removal of these species from the genus Gono- 
dactylus. Kemp (1913) and Edmondson (1921), 
however, did not consider these differences of 
a generic nature and retained the original 
name applied to the species by White (1861). 
Two specimens were kept alive for observa- 
tion in an aquarium. Both were females, one 
of which was collected with a mass of fertil- 
ized eggs; the other laid a mass of eggs in 
captivity. Both specimens survived very well 
even though they were both dredged from a 
depth of over 100 fathoms. The fertilized 
eggs developed until the time of hatching but 
then began to degenerate. Several eggs from 
the mass were removed at intervals and pre- 
served in 7 per cent formalin solution with 
the hope that eventually they might be used 
to describe the embryology of this species. 
One female molted once while in captivity 
and remained a mottled yellow afterward. 
Little has been written about the function of 
the elaborate spines on the telson; however, 
my observations have shown that the animals 
either burrow into the substrate or select holes 
in dead coral which are just large enough for 
them to crawl into. Ordinarily they are found 
partially emerged from their burrows but when 
