I. '08. 145 



very feebly so ; fifth sharply carinate ; sixth dorsally channelled 

 and bicarinate. On close examination the carinae of the 

 fourth and fifth somites are seen to consist of a J3air of fine 

 ridges which meet posteriorly. Telson dorsally snlcate, and 

 slightly longer than outer uropods. 



Basal joint of antennular peduncle longer than second and 

 third combined, its lateral process quadrate in outline, reach- 

 ing distal end of segment ; second joint longer than third. 

 Antennal scale (fig. 7 b) concave along its outer border, much 

 narrowed distally and three times as long as broad ; apical 

 spine long, projecting far beyond the lamellar poj'tion of scale. 



In this form, as in all the other species of Pliilochcras, the 

 chela of the second pair of pereiopods (fig. 7d), although of 

 comparatively large size, is weak and probably of but little 

 service to the animal. The dactylus is much more than half 

 the length of the propodus, but the inner margins of the claw 

 are almost parallel and their apices are not provided with 

 ungues. 



Size. — The largest specimen examined measures 38 mm. ; 

 Scott (190*2) records an example of 45 mm. 



Colour in life. — The carapace and abdomen are dorsally of 

 a somewhat greenish tinge, due to the admixture of lemon 

 yellow and sienna brown chromatophores ; laterally there are 

 numerous, large, dark maroon chromatophores along the in- 

 ferior margins of the carapace and on the abdominal pleura. 

 The telson is coloured with a mixed pigmentation of lemon 

 yellow, sienna, and maroon. The eyes are greenish black. 

 The antennal scale and antennules are sparsely mottled with 

 yellow and sienna brown. The outer maxillipedes are spotted 

 with maroon, with a few clear red chromatophores distally. 

 The first and second pereiopods are maroon, the former with a 

 few red spots at the terminal end of the propodus. In the last 

 three pairs of pereiopods the ischium is maroon ; in the third 

 pair the remaining joints are transparent, while in the other 

 two there are red chromatophores on the merns and carpus. 

 The pleopods are maroon, faintly tipped with red. 



Some specimens are very sparsely pigmented ; in these all 

 trace of the red pigment is frequently absent, while the lateral 

 maroon markings are very faint. 



General distrihution. — This species is not particularly com- 

 n^.on ; it is known from the western and southern coasts of 

 Norway, the North Sea, off the coasts of Scotland and on the 

 N. side of the Bay of Biscay. 



Irish distrihution.— On the east coast trawling grounds P. 

 echinulatus is not infrequently found, but it has not so far 

 been observed off the south coast. Off the west coast it has 

 been taken on the following occasions : — 



Helga. 



CXXI.— 24/8/'01.— 53° 52' N., 11° 56' W. 199 fathoms. Trawl. 

 Many, 9 5 — 29 mm, 



K 



