674 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.xx. 



first it is in a thin and weakly state, but soon recovers and gets plump 

 and fat, at which time it is most excellent eating. Thousands are pro- 

 cured from a small space of ground with ease, and hundreds of natives 

 are supported in abundance and luxury by them for many weeks 

 together. It sometimes happens that the flood does not occur every 

 year, and in this case the eu-kod-ko lie dormant until the next, and a 

 year and a half would thus be passed below the surface. I have often 

 seen them dug out of my garden, or in my wheat field, by men engaged 

 in digging ditches for irrigation. The floods usually overflow the river 

 flats in August or September, and recede again in February or March." 



This species has been well figured (in color) by McCoy. Different 

 specimens vary considerably in color, u some having the body and 

 abdomen dark olive, others paler or with a yellow tinge, and some are 

 of a dull pale brown or horn color ; the large anterior pair of claws are 

 always blue, with red joints, and the flexible part of the five tail fins 

 dull brown; the smaller pairs of legs are blue, or greenish, or whitish 

 in different living individuals." According to the same author, this 

 species is commonly known about Melbourne by the native name of 

 Yabber or Yabbie. It does not inhabit the streams, "but is abundant 

 in the quarry holes and swamps round Melbourne and in most water- 

 holes in the colony, doing great damage to drams and reservoirs from 

 burrowing holes through the banks. The individuals live for a long 

 time underground in their burrows after the pools of water on the 

 surface have dried up." Professor McCoy could detect no difference 

 between specimens from the swamps near Melbourne and those of the 

 Murray district. 



As noted above, the lateral teeth near the tip of the rostrum are 

 sometimes obsolete, and the proportional length of the fingers may 

 vary according to the size of the specimen. It therefore seems to me 

 probable that the specimen from Victoria in the Strasburg Museum 

 assigned to Cheraps preissii by Ortmann is in reality Cheraps bicarinatus. 

 The obsolescence of the lateral rostral spines is, in a few cases, accompa- 

 nied by an appreciable shortening of the rostrum, but, after examining 

 all the material before me, I can see no ground for forming two species. 



List of specimens examined: Australia, eight males, four females 

 (Coll. Mus. Comp. Zool.); Sydney, Australia, one male, one female (Coll. 

 Mus. Comp. Zool.) ; Melbourne, Australia, two females (Coll. Mus. Comp. 

 Zool.) ; no locality, one male, one female (Coll. Mus. Comp. Zool.) ; south- 

 ern Australia, two males (Coll. U.S.N.M.); Happy Valley Creek, South 

 Australia, two males (Coll. U.S.N.M.). 



For convenience of reference I append a summary of the Austra- 

 lian and Tasmanian species of crayfish that are doubtful or that are 

 unknown to me. 



