Mr. W. N. Lockington on American Alphei. 477 
which is about equal to first; outer branch of flagellum, in- 
cluding its slender terminal portion, nearly equal to inner, 
which is about equal to carapax. 
Spine of antennal scale longer than laminar portion or than 
peduncle of antennule, and equal to antennal peduncle; fla- 
gellum twice the length of the carapax. 
External maxillipeds longer than peduncle of antenne ; 
terminal joint margined with sete, those at tip very long. 
Meros of first pair spineless, that of smaller hand concave 
on outer surface. 
Hands of first pair unequal, dissimilar. Larger hand com- 
pressed, smooth, constricted above and below; at about the 
distal third of its length a sulcus, broad at commencement, 
but rapidly narrowing, running backwards longitudinally at 
right angles to the upper constriction on both outer and 
inner faces. Dactylus short, working obliquely, with a stout 
basal tooth, closing in a deep groove in the pollex ; the blunt 
tip of the dactylus crossing the sharp extremity of the thumb. 
Smaller hand rounded, smooth ; dactylus half the length of 
palm, working vertically, and equal to the pollex; tips of 
dactylus and pollex sharp, curved inwards, and crossing each 
other. Inside of both hands setose towards distal end, espe- 
cially the smaller. 
Ischium and meros of second pair equal; carpus five- 
jointed, second joint two thirds longer than the first, and 
longer than third and fourth together, third and fourth equal, 
fifth and first about equal. 
Meral joints of posterior pairs without spines; propodal 
joints spinulose beneath. 
Telson elongate; sides tapering; end slightly convex ; 
two pairs of spinules on the upper surface, and a third pair 
projecting from the extremity, which is fringed with long 
setee between the posterior spinules. 
Prevailing colour of specimens, after six months’ exposure 
to alcohol, red ; antenne blue. 
Length of the largest female 22 millims. ; length of larger 
hand 8 millims. 
Several specimens from Port Escondido, Gulf of Cal. (W. 
J. Fisher), collected in July to August 1876; the females 
loaded with ova. 
Alpheus parvimanus, Kingsley. 
Alpheus parvimanus, Kingsley, loc. cit, p. 195. 
Loc. Panama (Ff. H. Bradley). 
