46 Inheritance and Evohition in Orthoptera IT 

 EXPLANATION OF PLATES. 



PLATE I. 



BBQ and BQBQ, BCB and 73ece, and CCQ and COCe were photographed in pairs, 

 respectively, on the same plates and were printed in pairs. All nine kinds are here easily 

 distinguishable. 



The series of phenomena is here represented as due to the combinations of one pair of 

 allelomorphic characters, or factors, B and C, and a third character, or factoi-, 6, which is 

 not paired, or allelomorphic, except with its absence. 



This conception is widely different from that which represents the phenomena as due 

 to the combinations of two pairs of allelomorphic characters or factors. According to 

 Mr Bateson (2), p. 65, CQCQ, or BQBO might be considered one character of an allelo- 

 morphic pair. 



PLATE II. 



The top row (first twelve figures) represents the patterns which breed true and cannot 

 be further analyzed. The form J^ is most abundant in nature, most of the others being 

 comparatively rare. Therefore it is common to find the other forms hybridized with AA, 

 though they are sometimes found pure, or in combination with others than AA. 



The eighteen figures {BE — JS) represent simple hybrids resulting from combinations 

 of the pure forms. 



The remaining fifteen figures (BFB — CJQ) represent the pure forms and their hybrids 

 carrying the melanic pattern 9, heterozygously or homozygously, as indicated. 



For an explanation of the three figures /.S'7.S', BIS, and IIS see third instalment. 

 Journal of Genetics, Vol. vn. p. 47. 



LITERATURE CITED. 



1. Batkson, W., and Saunders, E. R. 1901. "Experimental Studie.s in the 



Physiology of Heredity." Report to the Evolution Committee of the Royal 

 Society. 



2. Bateson, W. 1900. Mendi'V.'i /'riiieiples of Heredity. Cambridge University 



Press. 



3. Child, C. M. 1915. SencKcenrc aticl Rejuvene.'ieenee. University of Chicago 



Press. 



4. Morgan, T. H., and others. lOl.'i. Mecliiiiiixtn (f Mendel i(n> Heredity. Henry 



' Holt and Co. 



5. Nabours, R. K. 1914. "Studies nf I nlici'itaiice ;uid EvohitioTi in Crthoptera. I." 



Ji)iiniid of O'eiieties, Vol. III. No. 3, ]t\>. 141 — 170. 



