THE APPENDAGES, THEIR INTERRELATION AND FUNCTION 



3ii 



Paragnaths (Fig. 8) 

 In the halocyprids the paragnaths are well developed. They extend ventrally immediately behind 

 and closely investing the hinder margins of the mandibular coxae (Fig. 8, p.g). Each paragnath is 

 triangular in shape and almost completely occupies the space between the mandibular coxa and the 

 protopod of the maxillula. The anterior margin, where it borders on the mandibular coxa, is edged 

 with a series of short fine bristles, which extend forward and inward towards the bristles on the margin 

 of the molar surface of the mandible. 



Functionally the paragnaths are important because they complete the lateral walls of the oral atrium. 

 The anteriorly directed spinules of their anterior borders aid retention of food material within the 

 atrium. 



Fig. 8. C. borealis antipoda. View enlarged from Fig. 7 of oral atrium, b.in, incisor edge of mandibular basis; c.in, incisor 

 edge of mandibular coxa; lb. I, labral lamina; Ib.s, labral socket; m, molar pads of mandibular coxa; m.c, molar claws; m.f, 

 bristle fringe of molar surface; m.t, molar tooth; mx x en x , pre-coxal endite of maxillule; mx l en 2 , coxal endites of maxillule; 

 oes, oesophagus; p.g, paragnath; v.t, ventral tooth of basal gnathobase. 



Maxillulae (Figs. 8, 9 & 10) 

 The maxillulae are uniramous, the endopod forming the palp and the protopod bearing well-developed 

 endites. They arise ventro-laterally, immediately behind the paragnaths and project vertically 

 downwards. 



The proximal article of the protopod, generally considered to be the pre-coxa, is very short. The 

 coxa is somewhat longer. There appear to be two endites (Fig. 8, mx 1 en 1 ,mx 1 en 2 , Fig. 9), the proximal 

 being pre-coxal, the distal arising from the coxa. The latter is, however, deeply bifid. It would seem 

 useful to adopt the view of Muller (1894 et seq.) and Skogsberg (1920), who considered this endite to 

 consist of two fused endites, comparable to the two distal endites of the cypridinids. The pre-coxal 

 endite bears a series of stout setae, of which the two nearest the body are brush-setae, the more distal 



