90 SCIENCE PROGRESS. 



to arrive at the immediate cause of the formation of peloria 

 by other means. Starting from observations made upon 

 wild plants he asked himself whether the formation of 

 peloria might not be determined by a change in the con- 

 ditions of life. Experiments with Galeobdolon liLfeuni and 

 Lammvi uiaculatiiui seem to indicate that this is actually 

 the case. These experiments, it is true, leave many im- 

 portant questions unsolved, but I mention them the more 

 readily in this place since an extended repetition of them is 

 greatly to be desired. 



In their natural habitat the Labiates just mentioned grow 

 in the shade of other plants. If the latter be removed, as, 

 for instance, by the clearance of wood in forests, many 

 peloric flowers, accompanied by other abnormalities, make 

 their appearance. It is thus reasonable to assume that the 

 increase in the intensity of light acts as the proximate cause 

 of these malformations, and the view that chang-es in the 

 conditions of life cause plants to vary is thus clearly sup- 

 ported. Plants were then exposed to a stronger illumination, 

 and although control-experiments, made by dividing the 

 stocks and placing a portion of the plants in normal (shady) 

 situations, were unfortunately omitted, it was found that 

 some specimens failed altogether to develop flowers ; in 

 one case the time of flowerino- was altered, and the flowers 

 were borne on shoots which do not normally carry them, 

 whilst three examples produced terminal peloric blossoms. 

 Two specimens were nearly normal, but even in these 

 the proportion of the floral leaves was abnormal in one 

 flower. 



In the following year the abnormal appearances were 

 less marked. The plants seemed, so to speak, to have 

 grown accustomed to their new conditions of life ; and 

 although the production of flowers was lessened, this was 

 doubtless due to the unfavourable influences operating upon 

 the sfrowth as a whole. Similar anomalies occurred in 

 Lammm maculatiun , though, as in Galeobdolon, these never 

 extended to the whole number of plants. Abnormalities 

 occasionally occurred in the vegetative region, but all the 

 plants did not react alike. It must be mentioned here, and 



