174 Pub. Puget Sound Biol. Sta. Vol. 2, No. 44 



PLATE 25 



ab.l, first abdominal segment. 



ch, chitinous exoskeleton. 



/', first pair of swimming feet. 



f", second pair of swimming feet. 



g.m, germinal mesoderm. 



i, intestine. 



I, lateral muscles. 



rra, dorsal muscles. 



st, stomach. 



•w, body wall. 



Fig. 20. Transverse section of first copepodid larva through low- 

 er portion of stomach (st). The muscles (m and 1) 

 and the germinal mesodern (g. m) can be seen to good 

 advantage . X 5 3 . 



Fig. 21. Transverse section of first copepodid larva through first 

 abdominal segment (ab. 1). Note the distinct intestine 

 (i). X530. 



