Victorian FresJt-ivater Amphijwda. 235 



extremity; the third short and narrow, and only half the length 

 of the second. The secondary appendage in the largest specimen 

 is formed of eight articuli. 



Lower Antennae. — These are densely clothed on the upper and 

 under surfaces with bunches of setae, those on the lower margin 

 being very long. The last two peduncular joints are long and 

 subequal. 



Anterior Lip. — Very small, stout, distally evenly rounded and 

 setose. 



Mandibles. — The left has the outer cutting edge broad, and 

 formed of five, and the inner of three teeth, and the spine-row 

 composed of about nine curved spines which are feathered on 

 their sides that face distally. The right mandible has four teeth 

 in the cutting edge, and a transversely cleft secondary process, so 

 as to form two ridges, each with denticulated edges ; the ridge 

 nearest the cutting edge contains seven small teeth, and is 

 limited on one side by a stout pointed prolongation ; the inner 

 ridge has about three little denticles, and a similar lateral pro- 

 longation to the other. Between this process and the molar 

 tubercle there is a spine-row of three or four feathered spines. 

 The molar tubercles are rather small, and bear a fringe of short 

 setae on one side of the distal margin. 



The palp is rather long, the first joint short, the second almost 

 of equal length to the third, and its under surface fringed by 

 bunches of long setae, the third is of normal form and armature. 



Posterior Lip. — Principal lobes broad, mandibular processes 

 short and poorly developed. 



First Maxillae. — -The inner lobe extends to half the length, 

 and the outer lobe to the extremity of the palp's second joint. 

 The inner one is narrow and bears on the inner half of its 

 summit three strong teeth and near their bases are two or three 

 long stiff" setae; also, conmiencing at the distal outer limit is a 

 row of plumose setae which run across to the opposite or iniaer 

 angle, and descend the margin for a short distance. 



The outer lobe is subovoidal, and its inner margin bordered 

 with a fringe of about sixteen spine-teeth, which gradually 

 increase in length to the apex and merge into a row of serrated 

 spinules that descend for a short distance along the outer margin. 



The palp is rather long, the third joint as long as the second, 



