474 Transactions.— Zoology. 
PraATYONYCHUS OCELLATUS. 
Cancer ocellatus, Herbut, ** Naturg. Krabben a Krebse,” Vol. ILI., p 61, 
Pl. XLIX., Fig. 4 (1799). Portunus pictus, Say., “ Journ: Ac. Nat. 
Sei. Phil," Vol. L, p. 62, Pl. IV., Fig. 4 (1817).  Platyonychus 
ocellatus, Latr., “ Encycl. Mith.," Vol. X., p. 152 (1825 ; M. Edw., 
“ Hist. Nat. Crust:,” Vol. L, p. 487 (1884) ; ** Archis. Mus: Hist. 
Nat.,” Vol. X., p, 415, Pl. XXXVI., Fig. 4 (1861). 
Carapace broad, very finely granulous, and with the regions scarcely 
marked. Latero-anterior margins divided into five well-separated acute 
teeth, which are directed forwards. Front narrow, and divided into three 
teeth, the median long and acute, the lateral ones shorter. Orbital margin 
straight, and divided by a single fissure. External maxillipedes long, the 
third joint deeply notched on the inner side for. the insertion of the mobile 
portion. Endostome smooth. Anterior legs moderate. Arm with five 
denticules upon its anterior margin. Wrist with two spines, one at its 
antero-internal angle, the other on its outer surface. Head longitudinally 
traversed with slightly granulous carine, and with a spine on the inside 
above the base of the mobile finger. Ambulatory legs short and. slender. 
Last joint of the swimming legs broad and oval. Abdomen of male tongue- 
shaped, five-jointed, the seventh very small and encased in the sixth. 
Hab. : Coasts of United States ; Gulf of Mexico. 
With reference to a doubtful form of Halimus, also submitted to Mr. 
Miers, he remarks :— 
“The Halimus, of which you showed a drawing, may prove to bea 
distinct species. It is evidently closely allied to H. hectori, Miers, the tuber- 
cles occupying the same position, but being in some places replaced by 
spines, also the rostral spines are longer and more acute. These differences 
may be due to age or sex. M. A. Milne Edwards has informed me that he 
described H. hectori as a new genus and species under the name of Ericho- 
platus huttoni, but I believe my name has the priority by a few weeks. 
Only an actual comparison of your variety with the type of H. hectori would 
enable me to determine whether it is really distinct, and whether M. Milne 
Edwards’ genus can be adopted." 
Mr. Miers also furnished a notice of an additional species to his cata- 
logue, and further notes referring to our fresh-water crayfish : — 
SQUILLA ARMATA. 
Squilla armata, M. Edw., ** Hist. Nat. Crust.," Vol. IT., p. 521 (1884); 
Gray, ** Hist. Chile. Zool," Vol. III, Crust., p. 223 (1849). 
M. Milne Edwards merely says of this species that “ it is very nearly 
allied to S. mantis, from which it is distinguished by the absence of crests 
