DECAPODS 151 
CALASTACUS INVESTIGATORIS Anderson. 
Calastacus investigatoris ANDERSON, Jour. Asiatic Soc. Bengal, LXV, Pt. II, 97, 
1896. _ Illustrations of the Zoology of the Investigator, Crustacea, Pt. 
Iv, pl. XXvV, fig. 1, 1896.—ALCOCK, Descriptive Catal. Indian Deep-Sea 
Crust. Dec. Macr. and Anom. in Indian Mus., 191, Igor. 
Distribution.—Taken by the Albatross, south of Sannak Islands, 
Alaska, 483 fathoms, station 3210, 1 Q ; off Cascade Head, Oregon, 345 
fathoms, station 3347, 1 ; off San Diego, California, 417 fathoms, sta- 
tion 2928, 29. 
Type locality.—Arabian Sea, off the coast of Sind, 947 fathoms 
(Lnvestigator). 
The antennal spines of one Californian specimen agree with Alcock’s 
description, while in the Alaskan and Oregonian examples the scapho- 
cerite and stylocerite are about equally produced; in the second 
Californian specimen the stylocerite is broken off. There is also variability 
in the spination of the upper margin of the merus of the large chelipeds; 
in one individual (from California) the whole margin is armed with spines 
which are proximally reduced in size; in the other three individuals ex- 
amined only the distal half of the margin is armed, as in the types. 
CALASTACUS QUINQUESERIATUS Rathbun. 
Calastacus quingueseriatus RATHBUN, Proc. U. S. Nat. Mus., xxiv, 887, 
1902. 
Carapace (rostrum included) measured in the middle line, as long as 
the first 5 abdominal somites ; its surface is pitted, especially on the infero- 
lateral portions, and a few feeble sete spring from the pits; cervical 
groove deep, branchial grooves indistinct. The rostrum reaches to the 
end of the second joint of the antennular peduncle and is tipped with a 
spine; its lateral margins are armed with 3 to 7 spines, and the pro- 
longations of these margins extend two thirds the length of the gastric 
region, are armed with 5 or 6 spines, and form a horseshoe on the cara- 
pace which is open behind and outlined in front by a groove a little 
posterior to the orbit. The median carina extends from the middle of the 
rostrum to the rear of the horseshoe and is from 2 to 6 (usually 3) spined 
atits middle. Between the median carina and the sides of the horseshoe 
is another row of 3 to 5 spines. The eyes are colorless and form a 
globular tip to the short eye-stalk. 
Expanded basal portion of the first joint of the antennular peduncle 
narrow-oval, bearing 1 or 2 marginal spinules near the tip. Stylo- 
cerite of antennal peduncle reaching to distal third of the penultimate 
joint; scaphocerite not reaching middle of the stylocerite. The external 
