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PACIFIC SCIENCE, VoL XIII, April, 1959 
lateral margins almost straight. Anterior dorsal 
spinules 0.3, posterior 0.6, of the length from 
articulation to tip. 
DISCUSSION: The only difference noted be- 
tween the incomplete specimen from Saipan 
and the type is that the propodus of the third 
legs carries 9 instead of 7 spines. 
This species plainly belongs to the Meg- 
acheles group, and to the A. hailstonei 
Coutiere complex (see Banner, 1953, p- 51 
et seq.). However, it can be sharply separated 
from all others of that group (including A. 
staphylinus Coutiere) by a series of characters, 
which include the broad second article of the 
antennular peduncle, the long stylocerite, and 
the nature of and direction of closure of the 
dactylus of the large cheliped. Other charac- 
teristics will separate it from one or more of 
the complex, as the presence of ischial spines 
will separate it from A. hailstonei hailstonei 
Coutiere and A. brachymenis (Banner); the 
armature of the dactylus from several others, 
etc. {op. cit., p. 55). 
It is difficult to state which of the known 
species of the complex is most closely related 
to the new species. On the basis of the anterior 
carapace, large chela, and third leg it appears 
to be closest to A. hailstonei paiicispinata 
(Banner). 
Alpheus collumianus medius Banner 
For synonymy, see Banner, Pacific Sci. 10(3) : 
340, 1956. 
LOCALITIES: 2 specimens, Station Y-215, 
Tomil Harbor, Caroline Archipelago; col- 
lected by R. W. Hiatt. One specimen, Jarvis 
Island, Line Islands, Itaska Expedition; col- 
lected by Toomey, Ahia, and Graf, 1935. 
One specimen, Wake Island (19°18'N., 166° 
35'E.), collected by C. H. Edmondsom, 
Tanager Expedition, 1923. 
DISCUSSION: Of the two specimens from 
Tomil Harbor, Yap, one was similar to the 
type in all respects, but the other, also similar, 
showed assymetry in the basicerites, with one 
normal for the subspecies and the other like 
that of A. c. inermis Banner (1956:342). 
The one specimen from Midway was also 
very similar to the type specimens except that 
its only remaining second leg had the carpus 
divided into six rather than five articles. The 
ratio of these articles was 10:2:9:4:4:7, show- 
ing that the extra article was the short one 
between the first and second articles. 
Alpheus seurati Coutiere 
Fig. 4 
Alpheus seurati Coutiere, Fauna and Geog. 
Maidive and Laccadive Archipelagoes 2(4) : 
881, pi. 75, fig. 20, 1905. 
LOCALITY: 1 Specimen from Jarvis Island, 
Line Islands; collected by Toomey, Ahia, and 
Graf, Itasca Expedition, 1935. 
DISCUSSION: This sole specimen of the spe- 
cies agrees almost perfectly with the descrip- 
tion and figures of Coutiere, although it lacks 
the small chela. 
Fig. 4. Alpheus seurati Coutiere. Third leg. 
This species is plainly most closely related 
to A. collumianus Stimpson and within A. 
collumianus to the two subspecies, A. c. medius 
and A. c. inermis Banner (1956: 340). Coutiere 
points out that the form of the anterior cara- 
pace, the large chela, the second legs, and the 
telson are like A. collumianus (actually, more 
like A. c. medius)] the differences lie in the 
stylocerite — which is like that of A. c. inermis 
—and in the third legs, where the merus is 
broadened and lacking an acute distal tooth, 
but bears rather a rounded protuberance. He 
also points out several other characteristics 
that differ, but these, like the relative lengths 
of the second legs and the presence or absence 
of spines on the carpus of the third legs, are 
