400 MEIOPHYLLY. 



in which all the little drupes which go to make up the 

 ordinary fruit were absent, except one, which thus 

 resembled a small cherry. In Cratcegus the pistil is 

 similarly reduced to a single carpel, as in C. monogyna. 



The writer has on more than one occasion met with 

 walnuts (Jiiglans) with a single valve and a single 

 suture.^ If the ovary of Jiiglans normally consisted 

 of two valvate carpels, the instances just alluded to 

 might possibly be explained by the suppression of one 

 carpel, but the ovary in Jiiglans is at first one-celled 

 according to M. Casimir de CandoUe. 



Among monocotyledons Convallarla majalis may be 

 mentioned as very liable to sujffer diminution in the 

 number of its carpels, either separately or in association 

 with other changes.'^ 



Meiophylly of the flower as a whole. In the preceding 

 sections a reduction in the parts of each individual 

 whorl has been considered without reference to similar 

 diminution in neighbouring verticils. It more com- 

 monly happens, nevertheless, that a defect in one 

 series is attended by a corresponding imperfection in 

 adjoining ones. Thus trimerous fuchsias and tetrame- 

 rous jasmines may frequently be met with, and Turpin 

 describes a tetramerous flower of Cohoea scandens. 

 Perhaps monocotyledonous plants are more subject to 

 this numerical reduction of the parts of several verti- 

 cils than are other flowering plants. Thus, in both 

 Lilium lancifoUum and Z. aiiratum the writer has fre- 

 quently met with pentamerous flowers. In Convallana 

 maialis a hke deviation not unfrequently occurs.^ M. 

 Delavaud has recorded a similar occurrence in a tulip.* 



Dimerous crocuses may also sometimes be met with. 

 In one flower of this nature the segments of the 

 perianth were arranged in decussating pairs, and the 



' See also Clos, ' Bull. Soc. Bot. Fr.,' xiii, p. 96, adnot. 

 - See Cramer, ' Bildtmgsabweich,' p. 7. Hildebrand, ' Bot. Zeit.,' xx, 

 1862. p. 209. 

 3 See Hildebrand, ' Bot. Zeit.,' xx, 1862, p. 209. 

 * ' BuU. Soc. Bot. Fr.,' viii, p. 287. 



