M Y S I D E A. 639 



G. 3. MYTO.* Pedes thoracis quatuordecim, primi secundi tertii quartique pal- 

 pigeri, quinti sexti septimi simplices. Appendices caudales segmentoque caudali 

 connati, ideoque cauda late triangulata, margine postico longo. Flagella anten- 

 narum internarum non articulata. 



FAM. III. LUCIFERIDvE. 



G. LUCIFER, Thompson. Antennas internac simplices, externaa squama basali in- 

 structas. Pedes thoracis quatuor postici (ad segmenta normalia pertinentes xiii. 

 xiv.), obsoleti; octo precedentes (ix. x. xi. xii.), elongati, setigeri; deinde duo 

 antici (viii.), instar maxillipedum flexi. Maxillipedes duo (vii.)j maxillaa quatuor 

 (v. vi.); mandibulas (iv.) duaa non palpigerae. 



APPENDIX TO THE MYSIDEA. 



The following genera are retained provisionally for certain imma- 

 ture forms, which may be young of Macroura : 



G. PODOPSIS, Thompson (Zoological Researches, i. 59, tab. 59, fig. 1). Oculi lon- 

 gissimi. Antennas internee fere obsoletoc ; secundaa lamina instructs. Pedes duo 

 longissimi, articulo tenui annulate confecti; reliqui breves. Pedes abdominis 

 natatorii. 



G. FURCILIA, Dana. Carapax plus minusve rostratus. Oculi aperti. Pedes abdo- 

 minis bene natatorii. Antennas internee furcatse, ramis (immaturis ?) subsequis 

 1-2 articulatce; segmentum abdominis posticum truncatum, extremitate saspius 

 spinulosum. Animalia in mari alto lecta. 



G. CALYPTOPIS, Dana. Carapax non rostratus, oculos omnino tegens. Antennas 

 internaa birameae, ramis (immaturis ?) subsequis, 1-2 articulatis. Segmentum ab- 

 dominis posticum truncatum, extremitate saepius spinuloso. 



FAMILY I. EUPHAUSID^E. 



GENUS EUPHAUSIA, Dana. 



Oculi breves, orbiculati. Antennce internee flagellis duobus confectce, 

 externcB squamd basali imtructce. Pedes tTioracici numero duodecim, 

 quatuor posticis obsoletis branchiis eorum exceptis, G-articulati, tenues, 



* Krbyer, Tids. N. R., i. 470. 



