36 
AUSTRALIAN FRESHWATER AND LAND CRAYFISHES 
Although somewhat resembling G. gracilis Clark, this 
species is distinguished by the form of the great chelae, the 
squame of the second antennae, and the sternal keel. 
Geocharax gracilis Clark. 
Geocharax gracilis Clark, Mem. Nat. Mus. Viet., x, 1936, p. 31, pi. i, fig. 8, 
pi. vi, fig. 26; Proc. Roy. Soc. Tasmania, 1938, p. 118, pi. xii, figs. 1, 
la, lb. 
Originally described from Victoria, this species has since 
been recorded from Smithton, on the north-west coast of 
Tasmania. 
Geocharax lyelli Clark. 
Geocharax lyelli Clark, Mem. Nat. Mus. Viet., x, 1936, p. 32, text-fig. 1. 
Since the original description of this species, it has been 
found in the following localities in Victoria: — Lima South, 
between Benalla and Mansfield (E. Clark) ; Swanpool (Mrs. 
G. Clark) ; Wandon, near Kilmore (A. Massola). 
Abundant in the flats along the Broken River, between 
Benalla and Mansfield, this species was found to be doing 
great damage to the maize crops growing in that area. 
It is interesting to note that the localities mentioned above 
are on the north of the Main Divide of the Victorian water- 
shed; the other species of the genus have been found only to 
the south of the Main Divide. 
Geocharax falcata sp. nov. 
Plate X, Fig. 5. 
Length of average adult specimen 80 mm. 
Rostrum broad, reaching base of third segment of second antennae; apex 
blunt, carinae sharp, arched broadly outward posteriorly, carried well back 
on to carapace; lateral carinae sharp, each ending in a rounded boss. 
Second antennae long and slender, reaching the base of third abdominal 
segment; squame large, reaching the end of third segment of first antenna; 
terminal spine short and sharp. Interantennal spine long and broad, sharply 
pointed. Median arch of upper lip smooth and swollen. Eyes moderately 
large. 
Carapace higher than broad, one and one-half times longer than broad, 
shorter than abdomen. Cervical suture deeply impressed, rounded; branchio- 
cardiac grooves feebly impressed ; areola broad. Branchiostegites and anterior 
of carapace studded with numerous minute tubercles. 
Sternal keel narrow, very sharp; first three pairs of lateral processes 
obsolete, fourth pair flattened downwards; sharp ridge of sternal keel con- 
tinued across fourth pair of processes. Processes between fourth pereopods 
long and stout, each with a sharp ridge on upper margin. 
Telson with a spine on each lateral margin at apical third; inner rami of 
uropods each divided by a longitudinal median carina, continued without 
spines to the posterior margin ; outer rami each divided by two longitudinal 
median carinae, inner carina continued across transverse suture, ending spine- 
