MUSEUM OF COMPARATIVE ZOOLOGY. 183 



branchial region. There is a medium spine on the second, third, and fifth ab- 

 dominal segments, and a rudiment of one on the fourth. The abdominal pleurae 

 have rounded external angles. The eyes are freely movable and destitute of 

 spines. The second antennal segment is armed with a prominent external 

 spine. The chelipeds are robust, setose, and granulate ; the merus has a short 

 superior spine and two lateral spines at the distal end; the carpus is similarly 

 equipped, though on one side the superior spine is obsolescent ; the chela is 

 broad and strong, the fingers excavated, denticulated on their cutting edges 

 and at their tips. The merus of the first pair of ambulatory appendages has 

 an external distal spine ; the carpus of all the ambulatory limbs has two longi- 

 tudinal ridges, and that of the first and second pair has a spine on the upper 

 border at the distal end of the joint. 



Length, 55 mm.; breadth, 18 mm.; length of carapace, 31 mm. ; rostrum, 

 8 mm. 



Station, 3394. 511 fathoms. 1 male. 



Munidopsis hystrix, sp. nov. 



Carapace setose and thickly covered with small spiny tubercles-; three 

 spines of special prominence on the gastric area disposed in the form of a 

 triangle with apex directed backward; one on the cardiac area; two (rarely 

 six) on the hind margin of the carapace ; one on each branchial area. There 

 is a spine at the external angle of the orbit, and the lateral margin of the cara- 

 pace is spinose. The rostrum is long, lightly curved upward from the base to 

 the tip, and armed with from two to five spines on each side ; these spines 

 are unsymmetrically arranged on the two sides. The second, third, and 

 fourth abdominal segments are conspicuously two-ridged; the second segment 

 has a pair of small spines on the anterior ridge, and another pair nearer the 

 median line on the posterior ridge; the third segment also has a pair of spines 

 on the anterior ridge, and in some specimens a third spine in the median line 

 on the posterior ridge. The abdominal pleurae are truncate. The chelipeds 

 are long, very spiny from the proximal end of the merus to the base of the 

 fingers ; the chief spines of the propodus are on the upper margin of the seg- 

 ment ; there are two spines near the base of the dactylus. The ambulatory 

 appendages are long, setose, and spinose except the dactylus joint. A spine 

 over the eye. Antennae shorter than the body ; a spine on the outer side of 

 the first segment, one on each side of the second and third segments, and one 

 on the upper side of the third segment. 



Length of ovigerous female, 47 mm. ; length of carapace, 25 mm. ; breadth, 

 15 mm. ; rostrum, 8 mm. 



Station 3417. 493 fathoms. 1 male, 2 females ovig. 

 " 3424. 676 " 4 females (2 ovig.). 



" 3425. 680 " 7 males, 5 females (2 ovig.). 



