224 



METABOLIC HORMONES 



Operated with / 

 saline / 



With brain 

 0'^^' extract 



injected 



(b) 



Fig. 5-19. Water uptake in larvae of Anisotarsus. a. The dotted 

 line gives the mean weight (ordinates) in 3 days (abscissae) for five 

 normal larvae, which remain constant in weight by diuresis. The full 

 line gives the mean weight of five initially rather smaller, operated 

 larvae (as Fig. 5-186) over the same period. Vertical lines show 

 the range of weights between the extremes in each group. These 

 do not overlap after the first day, b. Effect of injected extracts made 

 at the times marked by arrows. The curves give weights of indi- 

 vidual larvae, in which secretion of their own hormone was 

 prevented by section of the circumoesophageal connectives. 

 The full line shows an arrest in water uptake, i.e. facilitation of 

 diuresis, following injection of an extract of brain and corpora 

 cardiaca in 1 % NaCl. The dotted line shows continued water 

 uptake after injection of a control extract of suboesophageal ganglia 

 in 1 % NaCl ; salt solution alone gave a similar result (from 

 Nuiiez, 1956). 



