332. t. 24. f. 1 - 5.
agrees with this species in the form of the beak, but the keels on the
thorax are not noticed either in the description or in the figure; and
the caudal lobes in the figure appear most to resemble A. FRANKLINII.
As the genus ASTACUS is now becoming more numerous in species, it may be
divided, with advantage, into three sections, according to the form of
the caudal lobes; thus: -
A. The central caudal lobes divided by a transverse suture into two
parts, both being hard and calcareous, and with a small spine at the
outer angle of the suture (PATAMOBIUS, LEACH) as A. FLUVIATILIS of
Europe, and A. AFFINIS of North America, with an elongated rostrum, and
A. BARTONII of North America, with a short rostrum.
B. The central caudal lobe continued hard and calcareous to the end, as
ASTACUS FRANKLINII of Van Diemen's Land, and A. MADAGASCARIENSIS of
Madagascar; both have a very short beak, and the second abdominal ring
spinose.
C. The central caudal lobe continued or only slightly divided on the
middle of each side; but it and all the lateral lobes are thin and
flexible at the hinder parts, as ASTACUS QUINQUE-CARINATUS, and A.
BICARINATUS of Australia, and A. CHILIENSIS of Chili.
CATALOGUE OF REPTILES AND FISH,
FOUND AT KING GEORGE'S SOUND,
BY DEPUTY ASSISTANT COMMISSARY-GENERAL NEILL,
IN A LETTER TO J. E. GRAY, ESQ. BRITISH MUSEUM, LONDON.
