Plate 16. Third-Stage Lobster. 



Figure 22. (Second Stage.) Right third abdominal appendage (pleopod) 



from before, M=87. The pleopods of the second, third, fourth and fifth abdom- 

 inal segments appear first, but in a non-functional state, in the second stage. 



Figure 23. Bight first antenna from above, M = 4S. In the third stage the 

 segmentation of both exopodite and endopodite are clearly marked. The l.>asal 

 joint is of peculiar form and, the position of the auditory sac is suggested. 



Figure 24. Right second antenna from above, M = 40. By the third stage 

 the endopodite has grown out to exceed in length the exopodite. The former 

 shows distinct traces of segmentation, and seta^ have appeared between the seg- 

 ments. In this specimen the retraction of the body of the antenna due to the 

 beginning of the moulting process is shown. 



