229 



cases it takes the form of a cornute projection, which may be two 

 or three inches in length. 



However small the " navel " orifice may be it is point of weak- 

 ness in the rind of the orange, and renders it peculiarly liable to 

 " splitting." This is a term applied to the opening of fissures in 

 the pericarp, whereby germs of decay are admitted to the inte- 

 rior. Orchardists are not agreed as to the causes which produce 

 the tension within the orange, but the resultant ruptures often 

 occasion a large percentage of loss in the crop. 

 San Bernardino, California 



THE FATE OF A VIOLET, OR THE BENEFIT OF 

 CLEISTOGAMY 



By E. J. Hill 



The efficacy of cleistogamy in the preservation of a species 

 under adverse conditions of environment was well shown by a 

 case which came under my observation a few years ago. The 

 area now comprised in Hamilton Park, one of the smaller parks 

 of Chicago, is but a block from where I have lived since 1885, 

 and was familiar ground for botanical study and collecting for 

 ten years previous. It was in part undisturbed prairie ; in part 

 wooded by a scattered growth of oaks and shrubs in the dryer 

 portion. There was a low ridge of sand forming the southern part 

 of the area, with an herbaceous flora common to low sand dunes. 

 The remainder was wet or wettish prairie in which the sand was 

 mixed with humus a foot or more in depth, making a black soil 

 resting on the pure sand of the old lake bottom, akin to that of 

 the low ridge. The property being for a long time in litigation 

 was nearly all left vacant until used for the park, while the 

 grounds contiguous had been largely taken for dwellings. The 

 making of streets and construction of sewers served to drain the 

 wet sections, and as commonly happened in such cases some of 

 the plants of the dry ground moved into the drained portion to 

 associate with, or supplant, the less resistant original occupants ; 

 and plots where Cypripcdiwn candidwn, Viola blanda, V. lanceo- 

 lata, and the like once flourished were taken by Phlox bifida, 

 Viola pedata, and their associates. The last mentioned did this 



