Blume and Z. neglectum Val. (Pl. xv f. 5) show different degrees of accrescence 

 of the staminodes to the labellum. 



The construction of the lip and staminodes procures an excellent chara- 

 teristic for distinguishing the diverse species one from the other. Contrary 

 to some other genera such as Alpinia and Curcuma, [here are (in the Java flora) no 

 two species which could be confused because of the resemblance of the lip. 



Below 1 give an analytical key wholly based on the structure of tip 

 and staminodes by which the species are easily determinated if living 

 flowers are available. 



There is still a curious teratological modification of the flower to be 

 mentioned, which is always seen in some flowers of a cultivated form of 

 Zingiber atnaricans, (Heyne 66) (see PI. 15, fig. 16) Here the two anterior 

 petals are fused into one and at the same time the lip which is normally 

 distinctly emarginate or bifid at the top is quite entire. This fact seems to me to 

 speak in favour of the theory of Lestiboudois who considers the lip as to be 

 originated by the fusion of the two inner or petalar stamina, while according 

 to him the outer or sepalar stamen, which theoretically ought to be inserted 

 between the two anterior petals is supposed to have averted entirely. 

 According to K. Schumann however the two inner stamina have avorted 

 and the lip with the staminodes represents the outer staminal cycle. 



Now 1 think that if this were the case the bilobed structure of the lip 

 would not neccessarily be affected by the fusion of the petals, while, if 

 each of the halves of the lip represents a petalar stamen it may be expected 

 that with a fusion of the two petals also the petalar stamina (or labellum 

 lobes) should get more tightly connected, as happens indeed in this anomality. 



How this be the central vascular fascicle indicated by Costerus in 

 several genera and representing, according to him, the last vestige of the 

 avorted outer stamen, is never seen in Zingiber. 



The duration of the flowers in the species of Zingiber is, as well 

 known, very short, it differs in the different species and, in the cirum- 

 stances observed, is constant for each one of them. 



So the flowers i Zingiber Zerumbet begin to open before dawn but th. y con- 

 tinue to open till afternoon ; so there may be found open flowers all day 'ong. 



Those of Z aromaticuni be:}n to open at eleven a. m. and when cut 

 off they coütinue opening till eveiiing. 



The flowers of Z Ottcnsii open at t leven a. m. or st'll earlier. Those of 

 Z. amarxans (H. 66/ open after one p. m; cut off, th y produce oi-ly hi'f 

 opened flowers. Z. odoriferum does not open before 2 p. m. and conti- 

 nues till late in the evening, cut off, buds appear but remain closed. 

 Z. ieptostacfiym opens from dawn till dusk. 



The pollen is globose and finely reticulate though smooth pollen is 

 commonly considered as a character of the order. 



