Zoohgij.'\ NATURAL BISTORT OF VICTORIA. [^Crustacea. 



M. Gu^rin-Meneville in the Eevue Zoologique for 1840, p. 109, 

 establislied the geiius Astacoides for the large freshwater Crayfish 

 of the Madagascar rivers, maiuly distinguishing it from Astacus by 

 the supposed absence of the small basal scale of the outer antennae, 

 which however is distinctly present, as noted by Professor Dana in 

 the " United States Exploring Expedition : " but Erichson, in the 

 Archiv fiir Natm-geschichte for 1846, p. 86, in his " Uebersicht der 

 Arten der Gattung Astacus " re-defines the genus, noting that in 

 the males there are no appendages to the first abdominal ring, and 

 that those of the second ring are suiailar to those of the succeeding 

 rings, this being really the most important character of the genus. 



This gigantic species is now sent to the Melbom'ne market in 

 considerable quantity from the Murray by railway for the table 

 instead of lobsters, and is by far the most delicious of the few 

 Victorian Crustacea good for food. 



All the spines vary in size and nmnber, not only in different 

 individuals, but on the two sides of the same one. The blue 

 color is very much stronger in some individuals than in others, and 

 I notice (Bibl. Univ. 15 Mars, 1870) that some of the reddish 

 Crayfish in the rivers of S^vitzerland are said by local observers 

 to be blue when recently moulted. Some specimens are olive- 

 green where the blue appears in others. 



I can have no doubt that the A. spinifer (Heller) described by 

 him in the treatise on Crustacea in the "Voyage of the Novara," is 

 identical with Shaw's species, although the spines on the middle 

 lo1)e of the tail are more numerous than I have seen ; and it is 

 clear that Von Martens' A. armatus is also a synonym. 



Very common in the River IMurray, where it is caught by 

 lowering a piece of bagging, yn\\\ cords and floats to the four 

 corners, with some flesh in the middle ; this l)eing pulled up every 

 now and then shows three or four of the " Lobsters " feeding ; a 

 bit of meat at the end of a string suffices to catch them. 



Explanation op Figcees. 



Plate 15.— Fig. 1, side view of specimen, nitlier bluer tlian usual, half the natural size. 

 Fig. 1«, rostrum and base of antonnoj natural size of small speeimen. Fig. \b, anterior leg, 

 vieweil from inner side of small specimen, natural size. Fig. Ic, tail fin, half the natural size. 



Frederick McCoy. 



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