408 " THETIS " SCIENTIFIC RESULTS. 



is slightly cfirved at the extremity, and one-third shorter than 

 the sixth. 



The first pair of pleopods is elongate, and becomes somewhat 

 wider as the setose apices are approached ; the second pair is 

 narrowly lanceolate; the outer ramus is acute at the apex ; the 

 inner is oblique-truncated, and bears a long slender stylet on its 

 inner distal angle. Uropods acuminate smooth, with a few 

 scattered hairs along the margins. 



This species appears to be quite unique, the abbreviated joints 

 of the antennte, and the absence of adaptation for flexure of the 

 body at the fourth and following segments of the peraeon, sharply 

 define it from any species hitherto described. 



Three examples of this species were obtained off Wata Mooli, 

 in 54 to 59 fathoms. 



ARCTURUS OCULATUS, Beddard. 



Arcturus oculatus, Beddard, Chall. Rep., Zool., xvii., 1886, p. 102, 

 pi. XXV., figs. 1-4. 



Stations 37, 57. 



Three examples of this well-marked species were obtained off 

 Botany and Wata Mooli, in from 50 to 59 fathoms. 



ARCTURUS DENTATUS, sp. nov. 



(Figs. 115a-c.) 



Station 37. 



Adult female : — Body about 9 mm. long. Cephalon as long as 

 broad ; frontal margin slightly excavated ; antero-lateral angles 

 rounded ; superior surface with four stoutish spines ; the first 

 pair are situated in a line with the anterior third of the eyes ; 

 the second pair are on the posterior border ; their bases are wide 

 and in a transverse line with the hinder portion of the ocular 

 border. . 



The first to the fifth segments of the peraeon are armed 

 superiorly with three transverse rows of spines ; of these the 

 middle ones are the largest, especially those seated on the supero- 

 lateral aspect of the body ; the sixth and seventh have a single 

 row of small spines and a few compressed denticles. 



The pleon segments exhibit a few backwardly directed denticles; 

 the caudal shield bears about four sublateral denticles on each 

 side, the last pair l)eing rather large ; the extremity of the shield 

 is obtusely pointed. 



