0\ THE DEVELOPMEN'T OF Ah'.ANh:iXA. ö( 



clo.seiies.s of the ceplialif and anal lobes, and the formation of the 

 «toniodaïum (Agalcua'). 2 B. . ^ . 



Fig. 2(). A portion of the median longitudinal section of an eg<^ 

 in the reversi(jn stage, showing tlie expansion of the dorsum. 

 {A(jalena). 2 B. 



Figs. 27-o2. Longitudinal sections of tiie anal lobe in succes- 

 sive stages, showing the formation of the proctod^eum and the change 

 of the cœlomic cavity of the anal lobe to the stercoral pocket. 

 {Aijakna). 2 D. 



Fig. 33. A cross section of the anal lobe, sh(_)wing its unpaired 

 cœlomic cavity and gangli(jn, and its two lateral diverticula. (^Agalena). 

 2 D. 



Fig. 34. A sagittal secticjn of the alxlornen of an embryo after 

 the reversion stage. Two anterior abdominal septa are represented. 

 {Agalenci). 2 C. 



Figs. 35. 36. Sagittal sections of the coxal joint of the tirst 

 thoracic appendage, showing the communication of the cœlomic 

 cavity with the exterior by an ectodermic invagination. (^Agah'na). 

 2 D. 



Fig. 37. The glandular portion and the outlet of the coxal 

 gland. (Agaleua). 2 D. 



Fig. 38. A cross section of the céphalothorax, showing the 

 position of the coxal gland. (Agalena). 2 B. 



Fig. 39. A cross section of the poison gland of an embryo, a 

 little before hatching. (A galena). 2 D. 



Fio-s. 40-43. Portions of cross sections of the abdomen, show- 

 ing the formation of the dorsal circulatory organ. (^Agalcna). 2 D. 



Fig. 44. A porti(jn of a frontal section of an embryo in the 

 reversion stage, showing the three segments of the brain. (Agalena). 

 2 B. 



