24 FRESHWATER AND LAND CRAYFISHES OF AUSTRALIA 
Rostrum short and broad, reaching to base of third segment of first 
antennae, almost twice as long as broad at base, apex sharp with two blunt 
spines on each side ; carinae smooth and blunt ; lateral carinae blunt, ending 
in a rounded boss. 
Squame of each second antenna fairly broad, sharply pointed, reaching to 
end of third segment of second antennae. Interantennal spine short and 
broad, sharply pointed. 
Carapace shorter than abdomen, higher than broad, twice as long as broad ; 
cervical groove deeply impressed, areola fairly broad ; branchiostegites punc- 
tate, minutely tuberculate on some examples. 
Sternal keel very sharp; a long sharp backwardly-directed spine below 
great chelae ; first two pairs of lateral processes obsolete, third pair small 
and blunt, posterior pair larger, deeply grooved; processes between fourth 
pereopods long and stout. 
Telson with a spine on each lateral margin at junction of membranous 
portion ; inner rami of uropods each with a median spine and an outer lateral 
spine at junction of membranous portion ; outer rami each with several sharp 
spines along transverse suture. Lobes at base of uropods with upper lobe 
produced into a long sharp spine. 
Great chelae long and stout, propodus twice as long as broad, lower margin 
smooth, upper margin serrated; cutting edge smooth or with a few small 
tubercles; dactylus with one large tubercle in centre of cutting edge. Carpus 
with a large forwardly directed spine on upper margin. Merus with one or 
two small blunt tubercles on upper margin. 
Habitat. — Northern Territory : Port Essington (type locality). Western 
Australia: Kojonup; Harvey, Harvey River; Guildford; streams outside 
Mammoth Cave, and inside the Calgardup Cave, Cave district (McCulloch) ; 
Hillman; Darkan ; Korejikup; Toll’s Pass, Stirling Range. 
Types in British Museum. 
Described from two specimens from Gray’s type material, 
on loan from British Museum; compared with the two types 
of C. intermedins Smith in the National Museum ; and seven 
specimens from Western Australia. Specimens from both 
Gray’s and Smith’s material are figured for comparison 
(Plate V). 
(he rax bicarinatus s.sp. august its (McCulloch). 
Chacraps preissi var. angustus McC., Rec. West. Austrl. Mus., i, pt. 3, 
p. 231. 
“This variety differs from the typical form only in having more 
slender chelipeds and legs, and a slightly narrower carapace. The 
chelae are particularly narrow in my smallest specimens, and in this 
respect differ greatly from others of the typical form of about the same 
size in which they are almost similar to those of the adults. The 
colour, after long preservation, is a dark violet with light bluish areas 
on the sides and under parts. 
“The plate illustrates the only three specimens I have seen, which were 
collected for the Australian Museum by Mr. A. Abjornssen, near 
Albany. They are 141, 102 and 78 mm. long from the tip of the 
rostrum to the end of the telson, and the largest and smallest are 
females” (McCulloch, op. cit. ) . 
