470 MR. W. H. FLOWER ON PSEUDORCA MERIDIONALIS. [| June 13, 
corresponding ones. The inferior and external margin of the pro- 
podos, from the extremity of the dactyloid process to the carpal ar- 
ticulation, is convex, and longer than that of the intero-superior 
margin of the propodos and dactylos together. The carpus is armed 
with three blunt and one sharp anteriorly directed teeth upon the 
inner edge, and two sharp strong teeth upon the under surface. 
The meros is furnished with two rows of teeth, that converge toge- 
ther towards the ischium upon the inner surface. The other pereio- 
poda have little to attract attention. The second somite of the pleon 
has a tuberculous ridge just above the lateral margin. The inner 
scale of the posterior pair of pleopoda is furnished with a central 
row of short, sharp teeth; and the telson is armed with similar teeth, 
of which there are a few in the median line and others in two late- 
ral obsolete rows. 
The specimen from which the description is taken is a male. Of 
all the species of this genus, this form approximates the nearest to 
its marine allies, in the appearance of the great chelate pereiopoda, 
of any that we are acquainted with. The generally close resemblance 
of the several species of this genus is certainly very remarkable, 
when we take into consideration the vast geographical distribution 
that it. has—larger, perhaps, than that of any genus of Crustacea 
that is not of marine habits. Species have been taken in the frozen 
waters of North American rivers, in the hot latitudes of Chili, in 
temperate Europe and Tasmania, and now from the African island 
of Madagascar. We do not know of any having yet been recorded 
from the inland rivers of that continent. 
DESCRIPTION OF PLATE XXVII. 
Fig. 1. Astacus caldwelli. 
2. Carapace, seen laterally. 
3. Second pair of antenne. 
4, Squamigerous process of the same. 
2. NorE oN PsEUDORCA MERIDIONALIS, 
By W. H. Frower, F.R.S., erc. 
In the last volume of the Society’s ‘ Proceedings’ (1864, p. 420) 
I described two Cetacean skulls from Tasmania, presented to the 
Museum of the Royal College of Surgeons by Mr. W. L. Crowther, 
under the name of Orca meridionalis. Having obtained some further 
information regarding this species, I wish to add a few notes to my 
previous paper. 
As before mentioned, I had requested Mr. Crowther to obtain, if 
possible, a complete skeleton of the so-called “ Blackfish,” to which 
these skulls were said to belong. That gentleman, with a most 
praiseworthy desire to advance our knowledge of the Cetaceous ani- 
mals of the part of the world in which he resides, set to work with 
ereat energy to collect specimens; and among a most valuable 
