171 



RUBIACEAE. 



Mussaenda cylindrocarpa Bck. 



Habitat the East Indies. 



Coll. Sept. 1896, July 1897. 



As is well known the calyx-limb consists of five narrow lobes, 

 of which, however, one may broaden to a large petal-like organ, 

 which phenomenon is shown by a few flowers of the same 

 inflorescence. Our illustrations (figg. 90, 91) show that the 

 changed development may aff'ect also the other sepals, even 

 all of them at the same time. This fact is in contradiction 

 with Morren's opinion according to which the petaloid sepal 

 should be the outcome of a fusion of the said sepal with a 

 bract (Penzig II p. 36). Mr. Smith has also collected cases of 

 hexamery. 



Cinchona succirubra Pav. 



Habitat Peruvia. 



Coll. May 1898 by William Kessler, Tjampaca Warna, Garoet. 



Leaf bifid in connection with the fissure of the midrib. 



PosoqueiHa multijiora Lem. 



Habitat Brazil. 



Coll. May 1897. 



Two of the petals more than halfway cohering. 



Pentas carnea Bth. 

 Habitat West-Africa. 

 Coll. January 1898, June 1895. 

 I. Stem dichotomous; dichotomy introduced by flattening and 



grooves on the broad sides (fig. 92). 

 II. (The normal flower has five unequal sepals, and a five- 

 lobed corolla). 

 a) Flowers tetramerous. 



h) Flower according to the formula: K (5) P (4) M 4 C (?). 

 c) r, . . . . K(6)P(4) M4C(^); 



the extra-petals are placed on the inner side of two 

 others, consequently serial doubling. 



