23 



AN INTRODUCTION TO ZOOLOGY 



FIG. 125. Mysis oculala. (From Sedgwick after Sars.) 



nearly like the adult as does the 

 crayfish. The lobster, for ex- 



FIG. 126. Two stages in the develop- 

 ment of the shrimp, Pcnaus. A, 

 Nauplius stage ; B, Protozoaa stage. 

 (From Sedgwick after Fritz 

 Miiller.) 



B 



