34 CORA J. BECKWITH. 



Explanation of Plate III. 



Fig. II. Embryo of Amia, newly hatched, showing further development of the 

 four primary lateral lines, a. p., auditory pit; i.o.l.L, infra-orbital lateral line; 

 ■o.m.l.L, opercular-mandibular lateral line ; p.a.l.l., post-auditory lateral line ; s.o.l.L, 

 supra-orbital lateral line. X 2 °- 



Fig. 12. Embryo of Amia, one day after hatching, showing the four primary 

 lateral lines before definite sense organs are differentiated. X 2 °. a.p., auditory 

 pit; i.o.l.L, infra-orbital lateral line; o.m.l.L, opercular mandibular lateral line; 

 p.a.l.l., post-auditory lateral line ; s.o.l.L, supra-orbital lateral line. 



