264 Transactions. — Zoology. 



setae. Telson slightly concave above, narrowing towards the end, near 

 which are two very small setae on each side. Colour, whitish, semi- 

 transparent. Length i£ inch. 



Hub. Lyttelton Harbour. Three specimens taken in company with 

 numerous specimens of P. debilis. 



Genus Bircenna, novum. 



Body broad, coxae very shallow. Antennae sub-equal, upper without a 

 secondary appendage. Mandibles without an appendage. Maxillipedes 

 with well-developed plates on both basos and ischios. Gnathopoda equal, 

 not subchelate. Last segment of pleon and its appendages rudimentary. 

 Telson simple, not divided. 



Bircenna fulvus, sp. nov. PI. xxi., fig. 1, a to e. 



Head broad, depressed in front, antennae short, not longer than the head ; 

 both pairs of same length, slender. Peduncle of upper not distinguishable 

 from the flagellum, first joint about as long as the second, but stouter, third 

 shorter than the second, flagellum of about six joints, each bearing some 

 simple auditory cilia. Peduncle of lower antennas with four joints distin- 

 guishable, the last as long as the two preceding, flagellum of about four 

 joints. Both antennae with a few small setae. Maxillipedes short, the 

 plates on the basos and ischios reaching to the same point and nearly to 

 the end of the maxillipede itself. Gnathopoda equal and similar, ischios as 

 long as meros which is rounded at the end, carpus slightly longer than the 

 meros, expanded slightly distally, propodos slightly longer than the carpus, 

 of same width throughout, produced very slightly at its infero-distal angle, 

 a few small setae on inferior margin, dactylos stout, with a tooth on inner 

 margin, not bent back upon the propodos. 



First and second pereiopoda short, meros produced at antero-distal 

 angle. Three last pairs of pereiopoda increasing in size posteriorly, basos 

 of each much expanded. Coxae very shallow, broader than deep. Fourth 

 pleopoda with rami both longer than peduncle, acutely pointed, curving 

 upwards, one nearly twice as long as the other, fifth similar but stouter, 

 fifth segment of pleon very short, sixth apparently absent, sixth pleopoda 

 represented by a single joint bifid at end, outer piece rounded, inner ending 

 in a sharp point and bearing on inner margin four or five longish setae. 

 Telson short, triangular, with a seta on each side near the end. Length 

 £ inch. Colour, yellow. 



Hab. Lyttelton Harbour. 



I do not know where to place this peculiar-looking little Amphipod ; it 

 may come near to Phlias, but the species of that genius given in the 

 Catalogue of the Amphipoda in the British Museum are not described in 

 sufficient detail to warrant one in forming any definite conclusion as to 

 their relationship. I have only a very few specimens. 



