470 Mr. W. N. Lockington on American Alphei. | 
second and third; hand as long as fourth and fifth carpal 
joints. 
Meral joint of posterior pairs with a spine at distal extre- 
mity beneath ; propodal joints of all three posterior pairs 
spinulose beneath. 
Telson broad, rounded at extremity. 
Length 1:05 inch. 
Colour, in alcohol, a light flesh tint, much deeper on the 
large hand. A darker spot on the upper surface of the cara- 
pax, also on the anterior edge of the first two abdominal 
segments. 
This species lives in pools on rocky reefs at low-tide level, 
and is capable of producing, by clapping together the fingers 
of the larger hand, a snapping noise like that which can be 
made with the finger-nail. 
Loc. Santa-Barbara Island (S. A. L. Brannan) ; San-Bar- 
tolomé Bay, W. coast Lower California (W. J. Fisher). 
The above description is considerably amplified from the 
short and incomplete one published in the Proc. Cal. Acad. Sei. 
Kingsley’s description of his A. transverso-dactylus tallies 
exactly with my descriptions and with the specimen of A. 
clamator (a female) in my collection. His A. clamator differs 
from this in the want of a spine on the basal jomt of the an- 
tenn, in the proportions of the carpal joints of the second 
pair, in the want of a spine on the meral joints of the posterior 
pairs of limbs, and in the details of the hands. 
A. bellimanus is near this species ; but the rostrum is longer, 
there is no sulcus between eye-shields and rostrum ; the dac- 
tylus of larger hand is not swollen at the tip, and works hori- 
zontally; the palmar portion of the smaller hand is not 
unlike that of the larger, and has two spines in the same 
positions as those on the larger; the dactylus is thin and 
laminate ; and the meral joints of the posterior pairs have no 
spine below. 
Alpheus bellimanus, Lock. 
Alpheus bellimanus, Lock. Ice. cit. p. 34. 
Carapax slightly compressed; front three-spined, rostrum 
longest; no sulcus between eye-shields and rostrum ; basal 
spine of antennulee short, not reaching second joint of pedun- 
cle, second joint twice as long as third; inferior branch of 
flagella twice as long as the superior. 
A small spine on basal joint of antennee; spine of basal 
scale about as long as peduncle; flagella twice the length 
of the carapax, xternal maxillipeds longer than peduncles, 
