LYTHRAEIACEM. 



437 



a Fig. 410. Flower (f). 



I'ig. 411. Long. sect, of flower. 



opposite leaves and inflorescence similar to that of Lagerstroemia. It 

 is believed to be a native of Arabia or of the neighbouring countries, 

 African or Asiatic; it has been introduced into most tropical 

 regions. 



PempMs (fig. 410, 411), otherwise little different from most of the 

 preceding genera, belongs also to a small group (PempUdece), cha- 

 racterized by a va- 

 riation in the mode Femp/m adduU. 



ofplacentation. The 

 latter is nearly ba- 

 silar, that is, from 

 the base of the in- 

 ternal angle of each 

 ovarian cell rises a 

 small support on 

 which are borne 

 variable number of 

 anatropous, ascending ovules. The flower is moreover hexamerous, 

 with six accessory tongues in the intervals of the sepals, six petals 

 resembling those of Lagerstroemia, and twelve stamens, inserted at 

 two different levels on the receptacular tube. The fruit is capsular 

 and enclosed in the receptacle. P. acidula, the only species known, 

 is a small shrub observed at numerous points of the sea coast of 

 tropical Asia and Oceania. 



Lafoensia has the same mode of placentation as PempMs ; for the 

 two (incomplete) cells of the stipitate ovary have each a basilar 

 placenta, charged with erect ovules. But the flowers are 8-12- 

 merous, with as many accessory tongues as sepals, and a larger, 

 nearly campanulate receptacle. The fruit is a thick capsule, with 

 seeds bordered by a wing. They are woody plants of tropical 

 America, with opposite leaves and beautiful flowers solitary or united 

 in terminal clusters, composed of' cymes. Physocalymma has very 

 analogous flowers, but with eight parts and twenty-four stamens, 

 without tongues. The fruit is incompletely unilocular, with four 

 multiovulate placentae united in a basilar mass. The name of the 

 genus is derived from the receptacular sac growing and persisting 

 around the fruit after floration. P. florida is a flne Brazilian tree 

 with opposite leaves and the inflorescence of Lagerstroemia. Diplu- 

 sodon is from the same country ; it much resembles Lafoensia and 



