210 
VV. S. Faikbridge. 
llie specimens taken in Coclvbiim Sound appear to be identical with 
those found oft Ne^^' South Wales and figured by Dakin and Colefax (1940) 
as a variety of C. kroyeri (Giesbrecht, 1892) : the only difl'erence between 
these specimens and the rather few figures given for tlie Sydney variety, being 
tlie slightly larger basal portion of the cliola of the New South Wales speci- 
mens. While the male fifth leg of this species resembles C. kroyeri in some 
ways more nearly than C. typicns, the female abdomen and last thoracic 
segment are so entirely different from C. kroyeri, that it would seem best to 
regard it on these features as more nearly related to C, tyqdcus. Tt resembles 
C. typicus rather than C> kroyeri in a mimber of other points : the spines on 
the proximal segments of the first antenna ; the outer spine of the second 
exopod segments of the third legs ; and the length of the inner spine on the 
second segment of the female fifth leg relative to that segment. 
On comparison with some drawings made by Dr. A. G. Nicholls, tliis 
species appears to be identical also with a Centropagid found by him in 1939 
at Crawley Bay in the Swan River. Crawley Bay is well up in the Swan 
Inlet, and the salinity would be very low in winter : tliis form is therefore 
either originally or secondarily estuarine. Dakin and Colefax give no details 
as to where their specimens were found, b\it all or most of their collecting 
was done in the open sea. Since therefore, this variety is constant from 
New South Wales to Fremantle, in the open sea and under estuarine con- 
ditions, it seems best to give it specific rank. 
It may be most easily I’ecognised by the female abdomen and the form 
of the chela of the male fifth leg. 
Order HARPACTICOTDA. 
Family TISBIDAE Sars. 1904. 
Genus MACHAIROPUS Brady, 1883. 
Lang (1936) has revised this genus. Since tlien two new species have 
been described ; M. antarcticus (Lang, 1936b) and M. intermedins (Nicholls, 
1941). 
Machairopus cockburni sp. nov. 
Occurrence. — 8 females (3 ovigerous) and 10 immature specimens, in a 
horizontal haul at 10 m. depth ; 22-7-41. 
Female . — Length, 0 • 94- 1-15 mm. 
First antennae 9-segmented, tapering gradually, the proportional lengths 
of the segments being 1 8 ; 24 ; 32 : IS : 4 : 4 : 3 : 10 ; 14. Exopod of the 
second antennae 4-segmented ; the endopod bearing 9 terminal setae, 4 of 
w'hicli are geniculate. Second basal segment of the mandible bears a single, 
long, thick, plumose seta ; endopod and exopod typical. Exopod of maxilla 
bears 2 long plumose setae ; the endopod with 3 stiff serrate setae ; inner 
lobe I with 8 setae, and inner lobes II and III each with 2 setae. First maxilliped 
with an inner marginal lobe bearing 2 stout and 1 fine plumose setae, and a 
slender distal lobe bearing 2 setae. Second maxilliped with 1 stout claw^ 
apically and 3 finer setae. 
Proportional lengths of the segments of the endopod of the first leg 
10 : 6 : 3, each segment with a plumose inner marginal seta ; outer marginal 
spine of the second segment of the exopod in the middle of the margin, and 
the inner marginal bulge pronounced. Seta formula : — 
Endopod. Exopod. 
p2 1. 2. 230 1. 1. 223 
p3 1. 2. 330 1. 1. 323 
p4 1. 2. 230 1. 1. 323 
