BRACHYURA AND MACRURA OF HAWAIIAN ISLANDS. 
917 
Pandalus spinidorsalis, sp. nov. 
(PI. xxi, fig. 5.) 
Near P. bifurca (Alcock and Anderson). Surface microscopically rugose. Rostrum from three- 
fourths to four-fifths as long as rest of carapace, gastric carina reaching two-thirds length of carapace, 
armed with spines, of which about 7-9 are on the carapace, the posterior spines smaller and closer. 
Telson as long as the fifth and sixth segments combined, the sixth short. Outer pair of terminal 
spines more than twice as long as inner pair. Ocellus indistinct. Antennular peduncle reaching 
about two-thirds the length of the antennal scale, the latter being half the length of the carapace 
proper. The outer maxillipeds reach end of acicle, while the first pair of legs reach as far as the distal 
third of the terminal joint of the maxilliped. They are provided with a minute dactylus but no 
chela. Of the second pair, the left leg is the longer and slenderer, with a carpus of thirteen to four- 
teen joints and reaches almost to end of maxilliped, while the right scarcely reaches end of antennal 
peduncle and has a five to six-jointed carpus. The third, fourth, and fifth pairs of feet diminishin 
the order named, the fourth being nearer the length of the third ; the third exceeds the acicle by the 
dactylus and one-third of the propodus, while the fifth foot reaches middle of acicle; meral and 
carpal joints spiny below; succeeding joints setose. 
Dimensions. — Female, station 3986, length (exclusive of movable spines of telson) 47, length of 
carapace 13.5, of rostrum 9.8, of abdomen 23, of telson 6.5, of sixth segment 3.8 mm. 
This small species can be distinguished from most other species of Pandalus by the extension of 
the dorsal spines on the posterior half of the carapace. 
Distribution. — Kaiwi Channel, 295 to 310 fathoms, stations 3467 and 3472; south coast of Oahu, 183 
to 330 fathoms, stations 3813, 3914, and 3916; south coast of Molokai Island, 169 to 182 fathoms, station 
3835; Pailolo Channel, 277 to 684 fathoms, stations 3868, 3883, 3899, and 3900; vicinity of Kauai Island, 
55 to 362 fathoms, stations 3984, 3986 (type locality), 3998, 4001, 4130, and 4132; west coast of Hawaii 
Island, 147 to 232 fathoms, stations 4045 and 4047; north coast of Maui Island, 202 to 253 fathoms, sta- 
tions 4081 and 4083; northwest coast of Oahu Island, 241 to 282 fathoms, stations 4116 and 4117; north- 
east approach to Pailolo Channel, 290 to 286 fathoms, station 4095. Cat. No. of type, 30550. 
Heterocarpus ensifer A. Milne Edwards. 
(PI. xxi, fig. 7.) 
Heterocarpus ensifer A. Milne Edwards, Ann. Sci. Nat., Zool. (6), XI, 1881, art. 4, p. 4; Rec. PI. 
Exped. Travailleur, pi. xxvii, 1883. Bate, Challenger Macrura, 638, pi. cxii, fig. 4, 1888. 
Borradaile, Stomatopoda and Decapoda of Willey’s Exped., p. 413. Alcock, Desc. Cat. Indian 
Deep-Sea Crust. Dec. Macr. Anom., 107, 1901. 
? Pandalus carinatus Smith, Bull. Mus. Comp. Zool., X, 1882, 63, pi. X, figs. 2-2f and pi. xi, figs. 1-3. 
Heterocarpus carinatus Wood-Mason, Ann. Mag. Nat. Hist. (6), IX, 1892, 369. 
The specimens which have been referred to this species by different authors vary much in the 
dorsal surface of the first two abdominal segments. Bate describes and figures a low, thick carina on 
these segments* Alcock has the first carina faint, the second sharp, while according to Smith his P. 
carinatus has the segments evenly rounded above. A. Milne Edwards does not mention those seg- 
ments, but in a fair-sized specimen from the Caribbean 1 Sea (station 2359, Albatross ) there is a feeble 
blunt carina visible on both segments. The Hawaiian form resembles the typical or West Indian in 
this regard. The carinse of the third and fourth segments are more prominent and their posterior 
spine longer. 
This is one of the most abundant of the deep-water shrimps taken about the Hawaiian Islands. 
Distribution. — Kaiwi Channel, 220 to 375 fathoms, stations 3467, 3470, 3471, 3472, 3474, 3475, 3476, 
3893, 4105, and 4106; south coast of Oahu Island, 42 to 337 fathoms, stations 3810, 3811, 3813, 3814, 
3815, 3817, 3818, 3909, 3910, 3911, 3912, 3914, 3917, 3918, 3919, and 3920; south coast of Molokai Island, 
259 to 266 fathoms, station 3839; Pailolo Channel, 31 to 290 fathoms, stations 3865, 3866, 3867, 3883, 
3884, 3898, 3899, 3900, and 3901; vicinity of Laysan Island, 264 to 351 fathoms, stations 3952 and 3953; 
vicinity of Kauai Island, 55 to 469 fathoms, stations 3986, 3988, 3998, 4001, 4016, 4017, 4130, 4131, 4132, 
4134, 4135, and 4136; west coast of Hawaii. Island, 382 to 253 -fathoms, station 4041; north-coast of 
