BULLETIN OF THE UNTIED STATES FISH COMMISSION. 
106 
lobe. Third segment of antennular peduncle half as long as second. Basal scale short and broad, 
tipped with a spine, and falling far short of second segment. Antennal peduncle longer than antennular, 
its scale intermediate in length between the two peduncles; spine of scale long, projecting well beyond 
blade. Basal spine reaching line of anterior margin of first antennular segment. Propodus of large 
cheliped with upper and lower margins notched. Distal portion of outer face with three longitudinal 
furrows; crest between middle and lower furrows terminates in a spine between bases of fingers, as in 
A. mncroclieles; upper furrow continued posterior to notch by an oblique furrow passing over on to 
inner face. Superior margin of dactylus somewhat thickened and rounded. Smaller cheliped similar 
to that of macrochelex, but the margins of propodus are deeply notched and the superior groove of the 
outer face is oblique and continued on inner face, as in the large cheliped. Small chela of female much 
more slender and with longer fingers than in male. Carpal joints of second pair diminish as follows: 
First, second, fifth, fourth, third. 
Length of European specimen, 25.3 mm.; Porto Rican specimens all very small. 
Mediterranean; Cape Verde Islands (Stimpson, as . I . streptochirvti); Bermudas, ft. P>. ftoode 
(Kingsley); Cuba (Guerin); Key West (Kingsley) ; Santa Barbara and San Diego (Kingsley). Porto 
Rico: Puerto Real; Playa de Ponce; Arroyo; Ensenada Honda, Culebra. 
Alpheus formosus Gibbes. 
Alpheus formosus Gibbes, Proc. Amer. Assoe. Adv. Sci., in, 190, (32), 1S50. 
Alpheus poeyi Guerin, in La Sagra’s Hist. Cuba, 2d part, vol. VII, p. xrx, pi. n, f. 10, 1857. 
Rostrum flat, narrow-triangular, beginning at posterior line of the eyes, long-pointed and reaching 
or nearly reaching second antennular segment. Orbits with a slender spine, much shorter than 
rostrum. Antennular scale overreaching fij'st segment; second segment a little longer than third. 
Antennal peduncle longer than antennular; scale a little longer than peduncle. Basal spine reaching 
only to second antennular segment. Hand of larger cheliped compressed, without notches or grooves. 
Dactylus about two-fifths the length of palm, moving horizontally. Hand of small cheliped very 
slender; fingers as long as palm; a spine on inner face of palm, at base of the dactylus. The carpal 
joints of the second pair diminish as follows: First, fifth, second, third, fourth; the first joint twice the 
length of second. 
Length of ovigerous female, 17.3 mm. 
Porto Rico: Mayaguez; Mayaguez Harbor, 4 to 6 fathoms, station 6065; Playa de Ponce; off 
Humacao, 91 fathoms, station 6099; Ensenada Honda, Culebra; Fajardo. Key West (Gibbes); Cuba 
(Guerin); Bermudas (G. Brown Goode, coll.; also recorded by Verrill); Natal to Maceio, Brazil (Bran- 
ner- Agassiz Exped., 1899). 
Alpheus cristulifrons Rathbun. 
Alpheus obcso-manus Pocoek, Jour. Linn. Soe. London, Zoo!., xx, 520, 1S90 (nee Dana). 
Alpheus eristvlifmns Rathbun, Proo. Washington Acad. Sci.. n, 152, 1900. 
( >n the median line bet ween the eyes is a thin sharp crest, terminating in front in a short upturned 
rostral tooth, only slightly advanced beyond the orbital hoods, which have rounded margins without 
spines. Second segment of antennular peduncle nearly twice as long as third. Scale very short, not 
reaching second segment. Antennal scale a little longer than antennular peduncle and a little shorter 
than antennal peduncle; its thickened outer portion very wide, terminating in a spine, extending 
considerably beyond the thin inner blade. No basal spine. Propodus of large cheliped almost cylin- 
drical, very slightly compressed, in general appearance smooth. A faint notch on upper margin near 
dactylus. < )n the outer side a shallow longitudinal groove across the pollex, which is continued a short 
distance on palm. Dactylus a little less than half the length of upper margin of palm and moves 
horizontally. Smaller hand somewhat resembles the larger, except that it is less twisted, less cylin- 
drical, with dactylus and thumb straighter and relatively longer. The carpal joints of second pair 
diminish as follows: Second, fifth and first, fourth and third; the second being as long as the third, 
fourth, and fifth together. 
Length of an ovigerous female, 16.7 mm. 
Porto Rico: Playa de Ponce; Arroyo, on Light-house Reef; Ensenada Honda, Culebra. Fernando 
Noronha (Pocoek); Maceio, Brazil (Branner-Agassiz Exped., 1899). 
