574 



BULLETIN 54, UNITED STATES NATIONAL MUSEUM. 



transversal sutures detinino; the segments. Metasome rather short 

 and but slightly projecting, being conically tapered; its tirst segment 

 much larger than the others. Oral area placed wholly in front, com- 

 paratively broad, semicircular. AntennuUe very short, 3-articulate; 

 antenme much more slender and extended lateral!}', being composed 

 of 8 or 9 articulations successively diminishing in size distally. First 



Fig. 638.— Da,uis mysidis (After S.4r.s). a, Ventkai, view of female (adui,t). b, Oral area. 

 €, Dorsal view of adult female. <t, Right part of post-oral area wiTft corresponding five 



LE(iS AND INCUBATORY PLATES, g, LEG OF MALE. /, MaXILLIPED. g, MaLE (DORSAL VIEW), h, 



Lateral view of male. /, Head of male (ventral side). J, Specimen of Mysis mixta infested 

 WITH parasite, k. Uropoda of male. /, Uropoda of female. Ill, YorxG female (ventral 

 view). ?i, Young female (dorsal and ventral views), o, Young female (lateral view). 



pair of incubatory plates larger than the next succeeding ones and 

 divided ))y a ti'ansversal fold into two segments; last pair, extending 

 ])ehind the oral area, rather broadly overlapping each other in the 

 middle. Body of young female narrower. sul)clavate, with the meso- 

 some more distinctly segmented and the metasome more produced; 



