Passive Immunity to Infection with a Larval Tapeworm of the Albino Rat.

is common in the crossing of strawberry varieties but that it has not been recognized because of the similarity of the parent plants used. In the cases reported here, the parent plants were so strikingly different in size and appearance, in spite of their having the same number of chromosomes, that paternal and maternal inheritance could be easily recognized. The knowledge that this type of inheritance can be obtained from crossing two plants of the same chromosome number which readily hybridize is useful in making studies on inheritance, and it will obviate the necessity of working with crosses between plants of different chromosome numbers which are rather difficult to obtain.6