48 Proceedings of the Royal Society of Victoria. 



The only marked differences between the several species of 

 Hyalella and Chiltonia australis are that in the latter the first 

 maxillae does not possess a minute rudimentary one-jointed palp, 

 and the second pair of gnathopoda in the male is without a 

 conspicuous lobe to the wrist; but this latter difierence is only 

 one of degree, for it has a minute unarmed one, as shown in my 

 drawing. 



In Chiltonia mihiwaka, besides the loss of the maxillary palp, the 

 terminal uropoda are only one-jointed, and in Dr. Chilton's drawing 

 the wrist of the second gnathopods is quite without any lobe. 



Chiltonia australis therefore forms an interesting connecting 

 link between the New Zealand and American forms, and affords 

 good evidence of C mihiwaka having migrated from America to 

 New Zealand through Victoria, as some other forms of life appear 

 to have done. 



Through the kindness of Professor Baldwin Spencer, from 

 whom I received some material collected from Lake Hindmarsh,, 

 I am now able to add another species to this genus. 



Chiltonia subtenuis, sp. nov. (PI. IV.). 



Male. — Body comparatively slender, first four side-plates of 

 subequal depth to their respective segments. Epimeral plates of 

 last two segments of metasome with posterior angles a little 

 produced acutely backwards, ventral margins evenly convex. 

 Cephalon large, as long as first two segments of mesosome com- 

 bined, lateral edges deeply excavated. Eyes large, slightly oval. 



Mouth parts large and strong, possessing all the characteristics 

 of the type. Maxillipedes relatively stouter, but of quite the 

 same form and armature. 



Upper antennae equal in length to cephalon, and first three 

 segments of mesosome combined, peduncle with second and third 

 joints of equal length, each shorter than the first ; flagellum a 

 little longer than peduncle with about nine rather long joints. 

 Lower antennae a little shorter than the upper, gland cone 

 prominent, following joint produced below distally to a conical 

 spur tipped with setae ; flagellum of about six joints. 



First gnathopoda with anterior margin of side-plates slightly 

 produced anteriorly, lower margin evenly convex, carpus with 



