40 &. P. Whitfield—New Forms of Fossil Crustaceans 
question as to the possibility of their having been chelate at 
their extremities. As only the basal portions of these organs 
determined. aving had an opportunity of consulting 
A. S. Packard, Jr., in Biase to them, he gave as his caine 
that from their position and the representation of the other five 
pairs of thoracic members without them, they could not be 
other than antennal in their functions, notwithstanding their 
great size and anomalous character. Taking this view of their 
nature, the spoon would conform strictly to the type of 
Macrouran Deca 
n its generic ietans as well as in its general expression, 
the specimen resembles most nearly the genus Pygocephalus 
of Professor Huxley, first given in the Quart. Jour. Geol. Soc. 
London, vol. xiii, p. 363, 1857, with figures and descriptions 
of three specimens, under the name P. Co ooperi. Neither the 
genus nor species were well Saruaciiens at that time. Itis, how- 
ever, again referred to in vol. xviii, p. 420, of the same Journal, 
and a figure given of a specimen supposed to be of the same 
species, much better preserved, from the Coal shales at Paisley. 
ere are, however, too Di imbs represented as originating 
from the thorax for a Decapod; and the antenna, although 
roprensnted as of large size, are a like those of the Ohio 
ecimen, while there is a second pair shown. In other parts 
e fioure i is ingiesad and in the description the parts are no 
defined sufficiently for. close comparison. The differences, 
however, are so great that I shall propose for this form the new 
generic name PALZOPALZMON, with the following diagnosis. 
PALAOPALZMON, new genus. 
A Macrouran Decapod crustacean, having a shrimp-like 
body, with a thoracic carapace narro owed but not rostrate in 
front, and keeled on the back and sides. Abdomen of six 
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caudal flaps, one on each side, composed of five visible ele- 
pbs the outer four apparently anchylosed to form a single 
ma. triangular plate on each side of the telson. Thoracic 
ulatory appendages elongated, smooth and filiform, pad? 
the upper (second) joint, which is laterally compressed. 
dominal appendages short, the upper joints flattened or convex 
anteriorly, as if for the attachment of plates or fimbria. An- 
tennze with the basal joints strong and well developed, of large 
size, much exceeding in snes any of the thoracic limbs. 
Eye-peduncles short. Type P. Newberryi Whitf. 
