PROLIFERATION. 



11 



others ; sometimes it is absent altogether. In many 

 cases, especially where an ovary is present, the t£ eye " 

 at the apex of the whole series resembles that in a 

 normal fruit, and bears sepals. 



All such abnormal pears described in the literature 

 probably constitute essentially the same phenomenon t 

 though an attempt has been made, by Penzig and 

 others, to divide them into two sets, namely, those 

 which result from the formation of distinct flowers 

 one above the other, and those resulting from prolifera- 

 tion of the axis between the organs of one and the 

 same flower. Wittmack, for instance, describes a 

 three-storeyed pear of which he states that the lowest 

 storey represents the calyx-, the middle one the 

 corolla-, and the uppermost the stamen-region, the 

 floral axis being elongated between each set of floral 

 members ; but he adduces no evidence in favour of his 

 view. Buchenau describes a two-storeyed pear in 

 which, according to his view, the lower bore the usual 

 five sepals, and the upper one sixteen sepals spirally 

 arranged on the surface of the fruit, within them at 

 the apex being, as in the normal case, the remains of 

 the petals and stamens, while an ovary was present 

 inside. In an early number of the ' Gardeners' 

 Chronicle ' the spirally-arranged fleshy portions of the 

 second storey of an abnormal pear are, by the editor, 

 in one place described as sepals, and in another as 

 petals and stamens. The fact is that in such an 

 advanced stage of development it is impossible to 

 determine with certainty the nature of the organs of 

 the upper fruits ; in some cases it may be that they 

 represent petals and stamens. In some cases observed 

 by the present writer there were distinct remains of 

 petals immediately within the calyx of the lowest fruit 

 and surrounding the base of the second one ; hence this 

 latter could not have been constituted of the petals of 

 the lower one. The most obvious and natural solution 

 of the phenomenon is to regard in all cases each fruit 

 formed beyond the normal one as a distinct and sessile 



