ODONATA. 87 



White, tracheal threads extended from the inner side 

 of the pupa skin to the emerging dragon-fly. These 

 threads are seen in the dorsal and side views of the 

 pupa skin (Figs. 42, 42, ^f), and also in Fig. 43, ^, 

 which is a side view of the dry pupa skin from which 

 came the male dragon-fly (PL III., Fig. 31, p. 73). 



At 11.06 the animal threw itself forward and catch- 

 ing hold of the head of the pupa skin, withdrew the 

 abdomen quickly from its case. hX. 1 1 .08 it crawled 

 from the pupa skin to the netting. The body was 

 now short, light green in color, and covered with a 

 growth of delicate white hairs, particularly noticeable 

 on the thorax. The legs were colorless, the wings 

 white and short. The body trembled, the motion 

 being due, probably, to the exertion of pumping air 

 from the tracheae into the wings in order to expand 

 them ; gradually both the abdomen and wings grew 

 longer. At 11. 16 the dragon-fly walked a few steps 

 up the netting out of reach of the water, and re- 

 mained in this position till 1.5 1 p.m. At 11. 19 yellow- 

 ish spots became apparent in the wings. These organs 

 were extended upward from the dorsal side of the 

 thorax, and were held together and motionless during 

 the whole of this stage. The channel (see p. 76) was 

 now only indicated by a light-colored band down the 

 abdomen. At 11.53 the milky white appearance of 

 the wings had wholly disappeared ; they had become 

 transparent, and the first marked indications of dark 

 colored spots were seen in place of the yellowish spots 

 mentioned above. At 12.14 the dark spots were 

 distinct, and the channel also was clearly defined. At 

 12.45 a colorless drop like water fell from the abdo- 



