FLOWERS OF IMP A TIENS FULVA 159 



Masters (32) states that the balsams become peloric by the addition of 

 spurs. Penzig (38) takes the view that three sepals are present. The two 

 missing sepals sometimes reappear as small leaflets. In /. glandulifera, 

 all five sepals are present. Sometimes the side sepals are spurred and 

 sometimes all five when present. Britton and Brown (18) state in Im- 

 patiens fulva that "spurs are occasionally developed on the two small 

 exterior sepals, and spurless flowers have been observ^ed. " I have found 

 in I m pattens fulva not rarely spurs on the two small lateral sepals. These 

 spurs are generally much smaller than the posterior spur. Occasionally 

 the anterior sepal is found with the two spurs developed. These con- 

 ditions seem to be common to all flowers on the plants showing them. 

 These supernumerary spurs may develop in such manner as to prevent 

 the entrance of insects. The plants must then depend upon the cleis- 

 togamous flowers, or upon self-pollination in the chasmogamous flowers. 



General Organogeny of the cleistogamous Flowers; Morphology of Petals 



and Sepals 



The general organogeny of the cleistogamous flowers is the same as 

 that of the chasmogamous flowers up to the stage of the differentiation 

 of the spur in the posterior sepal. Figures 7, 8, 9 and 33 represent the 

 conditions in the cleistogamous flowers. Bennett figures and describes 

 4, p. 148) a difference between the buds of the two kinds of flower. 

 "The bud of the conspicuous flower (fig. 1) has the apex of the two 

 exterior (lateral) sepals hooked, while in that of the inconspicuous 

 flower (fig. 2) it is straight, the two buds at this stage being nearly equal 

 in size. The removal of the two exterior sepals shows a still greater 

 difference (figs. 3 & 4), the spurred posterior sepal or nectary being 

 very easily seen in the former case (fig. 3), while in the latter (fig. 4) 

 the interior whorls of organs are, as described by Prof. Gray, "nearly regu- 

 lar but never developing beyond a very minute size. " In earlier stages, 

 before the differentiation of the spur, this difference could not be de- 

 tected; cross sections, however, through the stamens, and especially 

 through the pollen sacs will prove the type of flower. 



In the mature cleistogamous flower all parts are present that are 

 present in the chasmogamous flower. Miss Riatt (39) says that the petals 

 are aborted in the cleistogamous flowers of Impatiens pallida, and Brit- 

 ton and Brown (8, p. 304) state for the family that the cleistogamous 

 flowers are apetalous. Knuth reports them present in the cleistogamous 

 flowers of /. noli-tangere (8, p. 52). They are evident in I. fulva (Fig. 

 9). Gray (18) figures them in his dissection of the cleistogamous flowers 



