86 



PRINCIPLES OF PLANT-TERATOLOGY. 



reversion to the immediately preceding ancestral con- 

 dition in which the outer whorl consisted of two 

 median and two lateral stamens. This condition has 

 in its turn been derived from an earlier one in which 

 the outer whorl of stamens consisted of eight members, 

 placed at equal distances apart, while the inner whorl 

 possessed four diagonally-placed members. This theo- 

 retical construction of the ancestral Cruciferous flower 

 drawn up by Celakovsky receives complete and full 

 substantiation from the structure of some abnormal 

 flowers of Gleome spinosn which he has placed on 

 record. This genus belongs to the Cappariclacese. 

 Normally this species of Gleome has the floral con- 



a b c 



Fig. 96. — a, Cheiranthus Cheiri (Wallflower). Outer whorl of andrce- 

 cium of four stamens, b, Cleome spinosa. (After Eichler.) c, The 

 same. (After Celakovsky.) Diagrams. 



struction typical of Cruciferse (unlike others with a 

 pleiandrous andrcecium). 



In one of the abnormal flowers the two lateral 

 stamens of the outer whorl had become petaloid, 

 although still bearing anthers. In the median posi- 

 tion, and also in the outer whorl, were four stamens, 

 nil in the form of staminocles, each bearing only half 

 an anther, and approximated in pairs. In the inner 

 whorl were four diagonally-placed fertile stamens. In 

 the centre of all whs a pistil of four carpels, the two 

 median ones being much smaller than the normal lateral 

 ones (fig. 96c). If this structure of the abnormal flower, 

 so different from that of the normal one, represents a 

 progressive phenomenon, it can, says Celakovsky, have 

 no bearing or explanation whatsoever on the structure 



