206 EEV. T. E. E. STEBBING ON NEW EXOTIC AMPHIPODA 



in general effect they are very like the conventional figure of a bird far off in the sky. 

 There are two arms, a little notched at the end, inclined to one another at various angles, 

 and, as it were, held together by a short central stock or handle, which projects most on 

 the convex side of the bow. 



In many specimens the large second gnathopod has a much more even palm than 

 that above described, with only a slight emargination or concavity above one third of 

 its length from the articulation with the finger, the finger at the same time having only 

 a slight bulge corresponding with the sinuous part of the palm not far from its hinge. 

 In correlation with this form of the gnathopod, the fourth peraeopod has its third and 

 fourth joints slender, not strongly dilated as above described. It is a question whether 

 these differences should lead us to speak of two forms of the male, as Mr. G. M. 

 Thomson suggests, or whether they are not only stages of development, the oldest 

 males acquiring the forms first described. 



It will have been noticed that in this species the development of the joints of the 

 peraeopod, which so much facilitates upright walking in Orchestia littorea and Orchestia 

 mediterranean does not occur, as in those species, in the last, but in the penultimate 

 pair of peraeopods. 



Mr. Thomson includes in his preliminary description the following remarks : — 

 " Colour, when alive, ivory-white. Hah. In sandbanks, Purakanui, near Dunedin, 

 among roots of littoral plants, many yards from high-water mark. Each specimen 

 inhabiting a hole of its own. When taken out they leap with great vigour." 



3. Pheeusa o^bulea, n. sp. (Plate XXXIX. fig. B.) 



Eyes minute, dark, difficult to distinguish amidst the deep blue of the head around 

 them. Ocelli composing the eye about twelve in number. 



The deep excavations of the anterior cephalic margin leave a short, but well-pro- 

 nounced, depressed rostrum between the upper pair of antennae, and on either side a 

 blunt process between the upper and lower antenna?, a little below the position of 

 the eye. 



The upper antennae considerably longer than the lower; first joint of peduncle 

 longest, much the stoutest; "auditory" cilia very minute; second joint not much 

 shorter than first ; third much shorter than second ; flagellum about three times as 

 long as peduncle, with numerous (33) joints slowly increasing in length and decreasing 

 in thickness towards the distal end. 



Lower antennae with large basal plate, small " renal " denticle, third joint short, 

 fourth the longest, scarcely as long as the first of the upper antennae, fifth rather 

 shorter than the fourth ; flagellum tapering, with nineteen joints, similar to the longer 

 flagellum of the upper antennae. 



Upper lip with distal edge nearly straight, a little convex, the converging hairs on 

 the border tolerably stout. 



