716 



THE AMEBIC AN NATURALIST [^ ol. XLI 



and paternal in character. The most remarkable case of gynan- 

 dromorphism that has ever been described, namely, that of the 

 Eugster hive, resulted from a cross between two species of bees, but 

 it is impossible to tell from von Siebold's description the specific 

 characters of the male and female parts. A test case is apparently 

 furnished in a recent paper by Toyama ^ " On Some Silk-w^orm 

 Crosses with Special Reference to Mendel's I^aw of Heredity." 

 Since Toyama has not attempted to draw any conclusion from 

 the interesting cases that he has found I venture to call attention 

 to their possible interpretation. 



A cross was made between two i-aces of sillv-worm moths; the 

 female belonged to a European breed haviiio; striped caterpillars; 

 the male belonged to the common Jai)anese breed having plain, 

 i. c. not striped, caterpillars. Two of the hybrid caterpillars 

 had the left side of the body striped (maternal) and the right side 

 plain. Applying my hypothesis to this case we see that the striped 

 side is due to the combined nuclei — the striped character carried 

 by the egg dominating the plain character of the s{)erm-nucleus; 

 the plain side is due to the sperm nucleus alone and is tlierefore 

 paternal. 



It might possibly be objtn tcd that the striixMl race was not jjure 

 but produced some phun lic ni cclN. so that the no-ht side is due to 

 this condition; but tliere is no cnkU'ikc that ihe striped race is 

 impure in this respect and tlie maiiv cxpcninents made by Toyama 

 with this race would have shown the nnpnntv had it existed.- 

 Moreover the striped concHtion of the h'tt side shows that the egg 



