Ceina, Chiltonia 555 



tbe 2\ 3*1 distally widened, not longer than 4*^^ Gnathopods 1 and 2 

 in 9 equal and similar, 5*^ Joint long, subtriangular, 6*^ rather longer, not 

 wider, oblong, palra sligbtly oblique, detined by palmar spine, finger matching 

 palm. Gnathopod 1 in d as in 9. Gnathopod 2 in d, 2'^ Joint naiTow, 

 5^^ apparently coalesced with the large oblong oval 6*^, which in smaller 

 specimens has a short transverse palm, but, the bind margin being gradually 

 produced, at length a complete tbough small chela is formed. Peraeopods 

 1 — 5 subequal, rather stout, almost uuarmed, 4**^ Joint rather expanded 

 distally, finger strong, curved. Peraeopods 3 — 5, 2*^ Joint rouuded oval. 

 Uropods 1 and 2 short, rami subequal to peduncle, spinöse. Uropod 3, each 

 member consisting of a Single, rounded, unanned Joint; the pleon segment 6 

 has the appearance of forming a peduncle to the pair. Telson subrectangular, 

 about as broad as long, apically rounded, cleft about to centre. Oolour red, 

 sometimes blue; integument thick, opaque. L. 6 — 7 mm. 



Lyttelton Harbour [New Zealand]. On sea-weed (Macrocystis). 



7. Gen. Chiltonia Stebb. 



1899 Chiltonia (Sp. un.: C. mihitcaka), T. Stebbing in: Tr. Linn. Soc. London, 

 ser. 2 V.7 p.408. 



Side-plates 1—4 deep. Antennae 1 and 2 equal in length. Maxiila 1 

 without palp, notched at palp's normal position. Maxillipeds, 4*^* Joint of palp 

 short, conical. Mouth-parts otherwise normal as in the family. Gnathopods 1 

 and 2 subchelate, gnathopod 2 very unlike in 9 and in ö. Uropod 3 

 1-jointed. Telson simple. 



1 species. 



1. C. mihiwaka (Chilton) 1898 Hyalella m., Chilton in: Ann. nat. Hist., ser. 7 

 ulp.423t.l8 I 1899 C7ii«oma m., T. Stebbing in: Tr. Linn. Soc. London, ser. 2 jj.7 p.408. 



Body stout, back of peraeon broad. Side-plate 4 much wider than 

 the preceding, much deeper than the foUowing peraeopods. Pleon seg- 

 ment 3, postero-lateral corners quadrate. Eyes small, round. Antenna 1, 

 peduncle rather long, 1^* Joint as long as 2^ and 3'^ combined, flagellum 

 subequal to peduncle, in 6 10-, in o 8-jointed. Antenna 2, gland-cone promin- 

 ent, ultimate Joint of peduncle a little longer than penultimate, flagellum 

 shorter than peduncle, in d 8-, in O 6-jointed. Maxillipeds, inner plates 

 with outermost of the 3 apical spine-teeth large, outer plates smaller than 

 inner, armed with fine setae, 4**^ Joint of palp with a long apical seta. 

 Gnathopod 1, 5*^ Joint as long as 6*^ bind margin fringed with about 15 

 long setae, 6*^ subrectangular, widening distally, palm nearly transverse, 

 well defined by a projection of bind margiu. Gnathopod 2 in 05^, 3'^, 4**^ 

 and S**! joints small, subequal, 5*^ not lobed, squared, 6*^ veiy large, oblong, 

 slightly widened distally, palm sligbtly convex, very little oblique, defined 

 by a process of bind margin, finger stout, inner margin slightly projecting 

 near base. Gnathopod 1 in 9 as in ö . Gnathopod 2 in 9 like gnathopod 1, 

 but 5*^ Joint shorter, subti-iangular, with only 5 or 6 setae. Peraeopods 

 3 — 5, 2^ Joint very broad, bind margin very convex, minutely serrate. 

 Uropods 1 and 2 well developed. Uropod 3 very minute, with no distinct 

 peduncle, the Single ramus pear-shaped and bearing a few minute setae, the 

 ramus here spoken of perhaps including the peduncle. Telson subrectangular, 

 angles rounded. Colour greyish or nearly white. L. reaching 5 mm. 



Xew Zealand. Mountain streams up to about 457 m; and at 731 m. 



