THE COROLLA. 403 



in their usual condition. In Odontoglossum AhxandrcB 

 a similar reduction of parts has been observed by the 

 author (fig. 199). 



It is curious to observe in these flowers how pre- 

 cisely one sepal occupies the position of the labellum, 

 and how the lateral petals are displaced from the posi- 

 tion they usually occupy, so as to form a regular flower, 

 the segments of which decussate, thus giving rise to a 

 species of regular peloria. 



The genus Moslenia was established on a malformed 

 flower of Oixhis of similar character to those above 

 mentioned. 



Meiotazy of the calyx. As already mentioned, this 

 term is here employed to denote those illustrations in 

 which entire whorls are suppressed. Complete de- 

 ficiency of the calyx in a dichlamydeous flower seems 

 seldom or ever to occur ; the nearest approach to it 

 would be in those cases where the calyx is, as it is 

 termed, " obsolete," but here it is chiefly the limb of 

 the calyx which is atrophied, the lower portion being 

 more or less adherent to the ovary. In what are termed 

 monochlamydeous flowers both calyx and corolla are 

 wanting, as in Salicmece and many other orders. 



Meiotaxy of the corolla. Deficiency of the entire corolla 

 occurs in conjunction with similar reductions in other 

 organs, or as an isolated phenomenon in the many 

 apetalous varieties of plants recorded in books. De- 

 ficiency of the corolla was observed in Campanula jyer- 

 foliata and RiielUa clandestina by Linne, who calls such 

 blooms flares Tmitilati} Drs. Hooker and Thomson 

 relate a similar occurrence in Campanula canesrens and 

 C, coloraia. Some plants seem as a normal occurrence 

 to produce flowers of different construction, and are 

 hence termed dimorphic, as in many Malplghia/^ew, 

 Vwlacea^t O.caUdacecey in some of the flowers of which 

 the petals are altogether wanting, while in others the 

 ^ ' PhU. Bot.,'T). 119. 



