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the smaller chela of the first pair of legs. In the females the
fingers are slender, straight, and acute, and scantily pubescent; in the
males the dactyl is relatively broader, snbspatiilate in form ; toward
the distal extremity the lateral margins are, closely and densely
fringed with hairs, which pass in an oblique line over the sides of
this joint, and meet on its dorsal surface immediately behind its
acute apex. Among the males the form of this (the smaller) chela
is subject to considerable variation; sometimes (as in Dr. Heller’s
Eed-Sea specimen iu the Museum collection) it is, as stated above,
smooth and entire, without notches or sulci, but it often exhibits a
gradual approach in form to the larger chela in having the upper
margins more or less distinctly notched, and even occasionally in
exhibiting traces of distinct depressions on the outer and inner surface.
As the two varieties appear to pass into one another by almost
insensible gradations, I have not ventured to distinguish them by
name. Of this latter form there are specimens from the Gulf of
Suez, Karachi, Samoa, and Shark Bajq West Australia (F. M.
Rayner, H.Al.S. ‘ Herald ’), in the Aluseum collection. Among the
Shark-Bay specimens (preserved dry) in the Museum collection
one, which is apparently a female, has a slight indentation on the
lower margin of the smaller chela.
Specimens from China (Gen. Hardwiclce)xa the Museum collection
are further distinguished by having a small spinule on either side of
the mobile finger at the distal end of the upper margin of each chela.
These have been designated by AVhite A . cJiiragrkus, AI.-Edw.,
whether rightly or not I cannot determine.
In certain specimens I have observed th at the interocular portion
of the rostrum is somewhat elevated and subcarinated, as in the form
from the Nicohars designated A . crassimanus by HeUer*, which may
perhaps be a mere variety of A . edwardsii. Dr. Heller notes a difference
in the form of the smaller chelipede in A. crassimanus exactly
resembling th a t I have described above as occurring iu A . edwardsii.
This character, I may add, seems to he alluded to by Hilgendorf f
in his remarks upon A . strenuus; but if so, th at author was not
aware of its being a mere sexual distinction, but apparently supposed
it to he a good specific character. I t is also mentioned by De
Alan, who, although regarding A. strenuus and A . crassimanus as
distinct species, regards the difference in the form of the smaller
hand as probably sexual J.
In the British-Museum collection are specimens of what appears
to be a distinct but closely-alhed species from the Eiji Islands,
Totoya {H.M.S. ‘■Herald ’), and Sandwich Islands ( W. H. Pease),
S. I. Smith {t. c.) it ranges from N. Carolina southward to the Abrolhos (Brazil),
and Lockington mentions its occurrence on the Lower Californian coast and at
Eealejo on the west coast of Nicaragua (as A. heterochelis) ; Dr. F. Eichters
records it from the Mauritius.
* Eeise der Novara, Crustacea, p. 107, pi. x. fig. 2 (1865).
t Alonatsber. der Akad. Wissensch. Berlin, p. 831 (1878).
] ‘Notes from the Leyden Museum,’ xxv. p. 105 (1881).
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which is distinguished by having a small but well-developed spinule
on the outer side of the antennal scale at base, and the fingers of
the smaller chelipede slender, arcuated, considerably longer than
the palm, thickly clothed with long hair on their inner margins, and
having between them an interspace when closed. In the adult the
fingers are sometimes elongated to a remarkable degree, three times
as long as the palm in one specimen. This form I propose to
designate Alpheus gracilidigitus.
Crangon monopodium, Bose *, is very possibly this or an allied
species. As, however, it is impossible to identify th a t author’s brief
description and rude figure as given in his second edition (1830) with
any species with certainty, and as his designation has never been
adopted by any subsequent writer, I prefer to retain Audonin’s name
A . edwardsii, about which there is no uncertainty and which has
been used by several authors of repute. I have never seen the first
edition of Bose’s work.
Both the Alpheus edivardsii, as described by Dana from Cape-
A*erd specimens, and the A . pacificus, Dana, from the Sandwich
Islands, differ in having the second joint of the carpus of the second
pair of legs much shorter than the first joint, but are probably mere
varieties of the typical A . edwardsii.
The species I described from the Samoa Islands as A . lineifer f is
allied to A edwardsii, but may he distinguished by the smoother
chelipede and the existence of a well-developed spine on the outer
side of the peduncles of the antenme. I t may perhaps he the young
oi Alpheusparvirostris, Dana, from the Balahac Straits ; but the first
joint of the carpus of the second pair of legs is relatively shorter,
and the large chela of the first pair relatively narrower and more
elongated than in Dana’s figure.
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6. Alpheus obesomanus, Dana.
A small example from Port Alolle, 5 -12 fms. (No. 118), is referred
to this species.
Several small specimens are in the British-Aluseum collection from
Ovalau, Eijis (H.M.S. ‘Herald’). Dana’s types were also from the
Fiji Islands. Dr. E. Bichters has recently recorded this species
from the Mauritius (Isle des Eouquets).
This species is remarkable on account of the turgid form of the
larger chelipede and the great elongation of the second carpal joint
of the second pair of legs.
7. Alpheus gracilipes, Stimpson.
I thus designate a specimen from Port Alolle, obtained on the
beach (No. 95), and another small example from Flinders Island,
* Hist. Nat. Crust, ii. p. 96, pi. xiii. fig. 2 (1802).
t Ann. & Mag. Nat. Hist. ser. 4, xvi. p. 343 (1875).