EDIBLE CmjSTACEANS OF NEW SOUTH WALES. 201 



and mentioKS that Dr. Hector had told liim that it is the same species as the 

 common Crayfish of the Sydney market. The difference between P. tumidns 

 and P. Jiiif/eUi he states to be, (1) the greater size of the former, (2) the 

 upward curvature of the beak, supraorbital, and antennary spines, and (3) 

 the telson in the former being less triangular, and rounded instead of 

 scarped. • Leaving size out of consideration, the upward (and forward) 

 direction of the spines mentioned is, so far as can be seen, present in 

 P. liugelii as described and figured by Heller ; and there is such a close 

 agreement in all other points between that species and the common Sydney 

 Crayfish that I am inclined to regard the concave posterior border of the 

 telson shown in the figure (but not mentioned in the description) to be either 

 an artist's slip, or the result of the wearing of the posterior thin edge of the 

 telson in the specimen figured. 



In young specimens of the Sydney Crayfish the spines on the carapace are 

 very prominent, and all, without exception, pointed as represented in the 

 " Eeise der Xovara," but in large specimens many of them become blunt, 

 and reduced to the appearance of tubercles, as described by Mr. Kirk in the 

 large New Zealand specimen, {Haswell.) 



This large and valuable crustacean exists in countless numbers along our 

 rocky shores, notwithstanding which the Sydney market is as a rule but 

 poorly supplied, and that from only a few localities, the principal of which 

 are Port Stephens, Cape Hawke, and sometimes Shoalhaven. Broken Bay, 

 which used to be the main source of the metropolitan supply, now furnishes 

 but few, this decadence being the result of the reckless destruction of the 

 breeding females. So abundant is this Crayfish, and, with proper legislative 

 precautions, so apparently inexhaustible the supply, that at but little expense 

 a great and profitable canning industry might with ease be established in our 

 various centres of distribution. 



This fine species grows to a weight of six pounds or even more. 



Family II.-ASTACIDiE. 



Carapace oblong, subcylindrical, rostrate, scarcely narrower than the 

 abdomen. External antenna; provided with a basal scale. First three pairs 

 of ambulatory legs chelate. Sternum narrow. 



Genus.— ASTACOPSIS. 



Astacopsis, Huxley, 1S7<S. 



Epistome long and flattened : basal joint of the antennfe fixed by the over- 

 lapping edge of the cephalostegite : squame short : posterior thoracic sterna 

 narrow : coxopodites of the hinder thoracic limbs large and approximated in 

 the middle line. Eostrum straight ; podobranchise not alate. 



ASTACOPSIS SEEEATUS. 



Cancer serrahis, Shaw, Zool. N. Holland, pi. viii. 



Astacus armatus, E. von Martens, Ann. Nat. Hist. (3) xvii. p. 359. 



Astacoidcs spinifei\ Heller, Voy. Novara, Crust, p. 102, pi. ix. 



Potamolius serrafiis, White, Proc. Zool. Soc. 1850, p. 95, pi. xv ; McCoy, 



Ann. Nat. Hist. (3) xx. 1867, p. 189. 

 Astacoides serratus, E. von Martens, MB. Ak. Wiss. Berl. 1868, p. 615. 

 Astacopsis serratus, Haswell, Austr. Malacostr. p. 171. 

 ? Astacopsis parramatfensis, Spence Bate, Voy. Challenger, xxiv. p. 202, 



pi. xxvii. f. 1, 18. 

 ^ Astacopsis si/dnei/ensis, Spence Bate, Toy. Challenger, xxiv. p. 201, pi. 



xxii. f. 2, 18. 



