154 BRITISH SERPENTS. 



en si 

 -thus 



men showed the eggs to be larger and more rounded 



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V 



Fig. 35. — Eggs of Addeh. 



The embryos were now quite distinct on opening an 

 egg, over an inch long when uncurled, the head being 

 prominent, and the eye the one dark spot in the general 

 yellow colour of the embryo. Up to this time the 

 female adder does not show much change in shape 

 externally, but in another month the size of the belly 

 is at once noticed. The embryos have now attained 

 the length of 2J inches. The eyes are still most 

 prominent, the mouth gapes, the body is about tlie 

 thickness of a good-sized worm, and the wall of the 

 belly is not closed in front in the middle line. 

 Development after this is very rapid, and by the 

 end of July great changes have occurred. I hap- 

 pened to get three on July 23, 1900, all extremely 

 large ones, one of which is figured with a male taken 

 at the same time, on p. 245. The female measured 

 26y'^ inches. She contained ten embryos in seven 

 eggs, which is a point not mentioned before ; but it is 

 not at all unusual to find an egg with two embryos in 

 it. In this case the left oviduct had two eggs and the 

 right oviduct five eggs in it. The eggs are now much 



