718 THE AMERICAN NATURALIST.  [VOL. XXXIII. 
63. Antennal scale moderate, rostrum elongate 
V. zostericola Smith M, Fig. 30 
63. Antennal scale as long as carapax; rostrum half as long as carapax 
V. pleuracanthus Stm. M, S 
G. Thor Kingsley. eure of second pair five-articulate. 
64. ‘ . T, floridanus Kingsley ‘S, Fig. 20 
Subfamily Pana. Carpus of second pair multiarticulate. 
G. Pandalus Leach. Itis at present impossible to frame a key for the 
species. 
65. P. borealis Kr. A, N. P. hypsinotus Brandt A. 
P. dane Stm. P, Fig. 27. P. leptoceros Smith N, M. 
P. dapifer Murdoch A. P. montagui Leach N, M. 
P. franciscorum Kingsley P. P. platyceros Brandt A. 
P. gurneyi Stm. D. P. pubescentulus Dana P, Fig. 53. 
ae Sub-family PALZMONIN#. Carpus of second pair never annulate, feet 
without exopodites. 
G. Pontonia Latreille. Rostrum short, external maxillipeds .expanded, 
with exopodite 
6. Carapax scat dactylus of larger hand of second pair with two teeth 
P. domestica Gibbes S 
66. Carapax pubescent; dactylus of larger hand with one tooth 
P. unidens Kingsley S, Fig. 40 
G. Anchistia Dana. Rostrum long, slender ; second pair of feet slender, 
equal. 
o o ; ; ; . A. americana Kingsley S, Fig. 10 
G. Palemonetes Heller. ours long lamellate; antennal and bran- 
chiostegal spines present; fresh or brackish water. 
8. Fresh-water species. : : i : ; ; . 69 
68. Salt or brackish water species . $ ee 5. 
69. Rostrum without teeth below P. antrorum Benedict. Well in Texas 
69. Rostrum toothed below. P. paludosa (Gibbes) Kingsley, South Caro- - 
lina, Great Lakes, Fig. 56. 
70. Rostrum straight . : P. vulgaris (Say) Stm. N, M, S, Fig. 47 
70. Rostrum recurved . ; P. carolinus Stm. M, S 
G. Urocaris Stimpson. Rivers toothed aori, toothless below; eyes 
elongate ; sixth segment of abdomen very long. 
n age : 3 ‘ . U. longicaudatus Stm. M, S 
G. Palemon F abelctink: Rostra lamellate; eyes free; mandibular 
palpus three-jointed. 
72. Hepatic spine lacking, marine ; ‘ Š .(S. G. Leander) 73 
72. Hepatic spine present, fresh-water 
P. ohionis Smith, Ohio and Mississippi rivers 
73. Rostrum with 10 to 12 teeth above, 6 or 7 below 
P. tenuicomis Say. Gulf weed, Atlantic 
ra 
