» ELISHA MITCHELL SCIENTIFIC JOURNAL 1 1 



By substituting- values the formula is deduced covering- the 

 kinds of hybrid offspring in their numerical relation for a 

 series of generations: 



D + 2 D R + R. 



This experimental result accords with what the law of 

 probabilities would lead one to expect in the averag-e of unions 

 of the pollen and egg" cells of the two parental forms. On the 

 average D pollen will fertilize equally often D ova and R ova, 

 and R pollen will fertilize equally often D ova and R ova. 

 The chances and the results may be exhibited thus: 



D. 



j D R 

 1 R D 



R = R, or D -f 2 D R + R. 



Mendel appears to have demonstrated that in the offspring 

 of a hybrid 25 per cent, will show the recessive character and 

 75 per cent, the dominant, embracing- 25 per cent, pure domi- 

 nants and 50 per cent, hybrids. Accordingly his contribution 

 to a theory of heredity may be stated to be the demonstration 

 of the segregation of characters in the totality of anorg-anism 

 and the individuality of characters, which is preserved down 

 the line of descent. 



A New Palaeotrochis Locality, with Some Notes on the 

 Nature of Palaeotrochis. Collier Cobb, Chapel Hill. (Illus- 

 trated by specimens and microphotographs, with the micro- 

 scopic sections displayed under a microscope). 



An acid volcanic rock full of spherulites closely resembling 

 Palaeotrochis occurs on the elevation three miles west of 

 Chapel Hill known as The Old Volcano. These spherulites 

 are smaller than Palaeotrochis, but they and the rock in which 



