298 M. WICHURA ON THE WINDING OP LEAVES. 



certain species right, in others left. Alphonse DeCandolle*' 

 has used the direction of the rolled buds in the descriptions of 

 the generic characters. His very accurate statements are made 

 use of in the following summary : — 



1. Parsonsieee, Alph. D.C., and Ec/dtece, Don: seeds with a 

 C07na above. Segments of the flower left in the bud. The 

 genera Neriandra, Alph. D.C., and Ecdysanthera, Hook., funu 

 exceptions with right-wound segments. Since, however, there 

 has not yet been any possibility of examining their seeds, it is 

 doubtful whether they actually belong here. 



2. Wrightiece, Don : seeds with a coma below. Segments of 

 the flower right in the bud. 



3. Alstoniece, Don : seeds with a coma above and below. 

 Direction of the segments of the flower variable. In Blaberopus, 

 Alph. D.C., they wind to the right ; in Adenium, Roem. et Schult., 

 left. The genus Alstonia, R. Br., includes several species with 

 left- wound segments of the flowers, and one other species in 

 which the segments wind to the right, — Alstonia scholaris, 

 R. Br. 



4. Plumeinem, Alph. D.C. : seeds naked, two separate ovarian 

 segments of the flower wound to the right in the bud in most of 

 the genera. They are wound to the left only in Kopsia, Blume ; 

 Odontadenia, Benth. ; Malonetia, Alph. D.C. ; Anisolobus, Alph. 

 D.C, and Thyrsanthus, Benth. 



5. WillughbiecB, Alph. D.C. ; Carissecs, Alph. D.C. : seeds 

 naked ; ovary simple ; segments of the flower right in the bud. 



A few other movements of winding of the parts of the flower 

 occur more isolated : — 



Thevetia neriifolia, Juss. : funnel-shaped corolla with five- 

 toothed border. In the bud it is weakly folded towards the left, 

 and at the same time wound heliacally in the opposite direction, 

 that is, to the right. Echites longiflora, Desf. : the left-rolled 

 buds slightly twisted together to the left above. For Christya 

 spinosa, Ward et Harvey; Strophanthus divergens, Graham, 

 and Str» dichotomus, D.C, see §§ 42, 43. Parsonsia spiralis, 

 Wall. ; P. oblonga, Wall. ; P. Cumingiana, Alph. D.C. ; P. heli- 

 candra, Hook, et Arn. : filaments left. Nerium Oleander, L. : 

 the filiform points of the anthers left. 



* DeCandolIe, Prodr. Syst. Natural, viii. 317-489. 



