182 PEINCIPLES OE PLANT-TERATOLOGY. 



Here also we may perhaps place those cases in which 

 staminodes revert to the condition of fertile stamens, as 

 occurs not infrequently in Fenfstemon and Scrophidaria. 



In the Orchidace^ Magnus observed in Dendrobiuin 

 WalUchU that the normally fertile stamen A^ of the 

 outer whorl had become staminodial, while the two 

 lateral staminodes of the inner whorl a^, a^ had 

 become fertile; while J. S. Henslow observed much 

 the same thing in Platanthera chlorantha. These cases 

 are interesting, for in G i/pripedium this structure of the 

 androecium is the normal one. 



In Gypripedium, where the large staminode, repre- 

 senting the anterior stamen of the outer whorl, 

 becomes fertile, the normally fertile stamens, a^ and a^, 

 of the inner whorl are also sometimes retained. A 

 case like this, abnormal in Gypripedium, is the normal 

 feature in Neuwiedia, which belongs to the Apostasiese, 

 a tribe closely allied to the Cypripedieae, both being 

 included in the sub-order Diandrse. 



Oaepellody. — A frequent phenomenon, revealing 

 to us the fact that stamen and carpel are very closely-, 

 allied organs, and the facility with which the one may 

 change into the other, doubtless due to the fact that 

 both are derived from a common ancestor, the asexual 

 sporophyll, which exists to-day in some of the more 

 primitive types of plants, such as ferns, horse-tails, 

 and some lycopods. A few instances of this pheno- 

 menon will now be cited. 



In Hermaphrodite Flowers. 



Beginning with those cases in which only a portion 

 of the androecium becomes carpelloid, Roeper men- 

 tions a flower of the garden tulip (Tulipa Qes^neriana) 

 in which there were only twelve floral leaves instead 

 of the usual fifteen, due to the fact that the inner 

 whorl of stamens had been transformed into three 

 carpels which alternated with the three outer stamens, 

 the normal whorl of carpels being suppressed. 



In a variety of the common poppy (Fapaver Rhoeas 



