IIO RATHBUN 
with ova (U. S. National Museum, No. 25,692). This species represents 
a more northern latitude than any Alpheid hitherto described. 
Affinities. —The species differs from &. longidactylus Lockington in 
its small hands, non-gaping fingers devoid of teeth, in the relative lengths 
of the carpal segments of the second pair of legs, in the shorter antennular 
spine, in the unequal peduncular joints of the antennule, as well as in 
some minor respects. } 
Family ZYSIZA 7/DZ. 
Genus Processa Leach. 
PROCESSA CANALICULATA Leach. 
Processa canaliculata LEACH, Mal. Podoph. Brit., pl. XLI, and correspond- 
ing text, July 1, 1815.—RATHBUN, Bull. U. S. Fish Comm. for 1900, 
vol. Il, p. 104, 1901, and synonymy. 
Two specimens of unusual interest were taken at San Diego, Califor- 
nia, by D. S. Jordan, in 1880. They are about 22 mm. long, and differ 
from typical specimens in having the left foot of the first pair similar to 
the right, or chelate. One specimen is a female, and has both chelipeds 
present. The other is so mutilated that the sex is indeterminable; it has 
a left cheliped, the right is missing. This form might perhaps be deemed 
a distinct species or genus were it not that among a lot of specimens 
from Cedar Keys, Florida, both forms occur. From this locality they 
are small (12 to 15 mm. long), and five specimens are bichelate, while 
four have only a right cheliped, the left foot being simple, as in typical P. 
canaliculata. These two forms from the same locality present no other 
appreciable difference. 
Aside from this remarkable dimorphism in the left first foot, the species 
is a most variable one. The rostrum may be half as long or nearly as 
long as the eye. The eyes, while always of good size, are not uniform, in 
some cases larger and more reniform, with the cornea extending on the 
outer side almost back to the carapace. The second joint of the anten- 
nulz varies from one and a fourth to twice the length of the third joint. 
The antennal scale may be a little more than half as long as the carapace 
(rostrum excluded) or even two thirds as long as carapace; it may be just 
as long as the antennular peduncle, or distinctly longer. Of the speci- 
mens examined, those from the west coast of Mexico and Panama Bay 
have the largest eyes; they agree fairly well with the description and 
figure of Bate’s P. processa from Amboina, 15 fathoms. 
1 The type of B. harrimani has been compared with Dr. Holmes’s description of 2B. 
longidactylus (Occas. Papers Calif. Acad. Sci., VII, 190, 1900), specimens of that 
species not being at hand. 
