No. 443.] 



MUTATION AV PLANTS. 



761 



the fact that the hairs on both surfaces were both Vnv^QV and 

 more numerous than on the parent type. The average length 

 of the hairs on the upi)er surfaces was 35 as compared to 28 

 in the parent type, and on the lower surfaces 42 as compared to 

 30. The average number of stomata on a unit of area of the 

 upper surface of the leaves of nibrincnns was 37 as compared 



Fig. %.—<Enotheta rubrinervis. Adult plant two weeks after beginning of opening of flowers. Photograph of living plant 

 grown in the soil in the open air, and temporarily fixed in a pot. (See Fig. 7.) 



with 34 in Uiiiotlicra lamankiaiia. The brittleness character- 

 istic of the tissues of nibrincivis may be seen to extend even to 

 the hairs, since these structures are easily detachable from the 

 dried specimens, and hence giving rise to the conclusion that 

 lubrincn'is is less densely pubescent than lamankiaiia as given 

 in the systematic description below. 



