196 THE VOYAGE OF H.M.S. CHALLENGER. 



cervical sulcus. Lateral walls tuberculated. with two irregular rows traversing the 

 upper portion of the branchial region and two or three sharp-pointed teeth on the 

 anterior portion of the branchial and hepatic regions. 



Pleon dorsally smooth and laterally furnished with numerous large spine-like teeth 

 that increase in number and lessen in size on each somite posteriorly. 



First pair of pereiopoda large, chelate, subequal. Margins furnished with small teeth, 

 a double row being on the outer side of the propodos. 



Second and third pair chelate, fourth and fifth subchelate and spinous. 



Pleopoda absent from the first somite. Those of the four following are biramose. 

 That of the sixth somite is large and foliaceous and forms the outer plates of the 

 rhipidura. The outer plate is furnished with a finely ciliated diseresis. 



Telson broad, rounded posteriorly, dorsal surface having many small sharp teeth ; 

 posterior margin crenulate. 



This species has been fully described and carefully figured by Dr. Camil Heller in the 

 volume on the Crustacea taken during the cruise of the Austrian frigate " Novara," under 

 the name of Astacoides spinifer. The year 1865 is appended to the several plates, but 

 the publication of the volume took place in the year 1866. In the month of May in 

 this latter year this same species was also described under the name of Astacus armatus, 

 with considerable care and minuteness, by Dr. E. von Martens, who specially remarks on 

 the resemblance of the scaphocerite of the second pair of antennse, and of the diaeresis of 

 the outer plate of the rhipidura to the same parts in Homarus. 



Both these accomplished zoologists were cognisant of Astacoides nobilis, Dana, with 

 which they compared it, and they affirm that it was easily distinguished by the form of 

 the rostrum, that of Astacoides nobilis being smooth at the sides and rounded at the 

 extremity, that of Astacopsis spinifer being sharp at the extremity and armed with 

 teeth along the sides. 



In the Memoir on the Crayfish by Professor Huxley this species has again been 

 figured, one-third of the natural size, under the title of an Australian Crayfish. He adds 

 in a footnote, " The nomenclature of the Australian Crayfish requires thorough revision. 

 I therefore, for the present, assign no name to this Crayfish. It is probably identical 

 with Astacoides nobilis of Dana and the Astacus armatus of von Martens." 



Length, measured from the extremity of the rostrum to that of the telson, 200 mm. 

 (8 in.) male. 



Habitat. — Paramatta River, Sydney, New South Wales. Heller gives New Holland 

 as the locality of the specimen he has described, and Dr. von Martens states that his 

 was taken from the Murray River in Australia. Thus it would appear that this species 

 is tolerably well distributed in the provinces, and probably exists in many if not in 

 all the rivers in the southern portion of the great Australian continent, and is probably 

 identical with that mentioned by Dr. J. Gray in a paper on the Australian Crayfishes, 



