34 U.S. NATIONAL MUSEUM BULLETIN 236 



Antennules 10-segmented, 6th free segment very long. Total 

 length of antennule is equal to about half length of cephalic somite. 

 Segmentation of antennule results from fusion of various segments of 

 originally 25-segmented antennula in following way: 

 1 2 + 3 4 + 5 + 6 + 7 8 9 10+11 + 12 + 13+14+15+16+17+18 19 + 20+21 

 12 3 4 5 6 7 



22 23 24+25 

 8 9 10 



Segment 6 shorter than combined lengths of segments 7-10; setation 

 of antennule shown in figure 6c. 



Antenna 4-segmented, exopodite fully absent. Coxa with sensory 

 internal and normal external seta. Bases with internal seta halfway 

 along its border. Endopodal segment 1, with 1+3 setae (1 internal, 



3 at end of internal margin); endopodal segment 2, with 5 marginal 

 setae and 1 appendicular seta (fig. Qd). 



Mandibular palp in my dissection detached from praecoxa and 

 exopodite partly concealed. Cutting edge of praecoxa (fig. 6e) with 

 7 strong teeth and basal seta. Fused coxa and basis large, without 

 setae. Exopodite well developed, 4-segmented; number of setae 1, 

 1, 1, 2, respectively. Of the 2 setae on the apical (4th) exopodal seg- 

 ment, one is lengthened, slightly thickened, and crowned by a tuft 

 of hairs. Endopodite small, 2-segmented; the setae number 3 and 



6 respectively (fig. Of). 



Maxillule (fig. 6g) with well-developed arthrite with 7 marginal, 

 spiniform setae. Coxa and basis fused, endites weakly indicated 

 and with 3 and 2 setae respectively. Exopodite small, rounded, with 



4 strong, plumose setae; endopodite unsegmented, with a total of 



7 setae, 3 of which are small. 



Maxilla (fig. 6h) with indistinctly separated praecoxa and coxa; 

 each with 2 scarcely elevated endites, bearing 1, 1, 2, and 3 setae 

 respectively; the distal endite is best developed. Basal endite well 

 developed, with 2 strong, curved spines, one of which is coalescent 

 with the lobe, and a seta. There are 2 more segments, probably 

 representing a 2-segmented endopodite, with 2 and 5 setae respectively. 



Coxa of maxillipede with 3 lobes, bearing 1, 2, and 2 setae respec- 

 tively. Basis large, triangular, with 2 setae. Endopodite short, 

 3-segmented, bearing 1, 1, and 2 setae respectively (fig. Qi). 



Figure 6. — Cychpina brachystylis G. O. Sars, loc. 589, ad. ?: a, 5th thoracic somite and 

 genital somite, ventral view; b, left furcal ramus with setae, dorsal view; c, antennule; 

 d, antenna; e, cutting edge of mandibular praecoxa;/, mandibular palp; g, maxillipede; 

 h, maxilla; i, maxillipede. (X 460.) 



