58 



NATURAL HISTORY OF PLANTS. 



Zizyphus vulgaris. 



Paliurus (fig. 49) was formerly ranged among the Jujubes 

 (Ziggphus), and gave its name to a separate tribe because its semi- 

 inferior ovary was succeeded by an indéhiscent fruit with a one- or 

 many-celled putamen. The hard and dry 

 pericarp is dilated above into a wide orbicu- 

 lar and horizontal wing. They are prickly 

 shrubs of temperate Asia and the Mediterranean 

 region. The true Jujubes (fig. 50-53) have, 

 like them, spinous branches, and alternate 

 3-5-nerved leaves; but the fruit is a drupe 

 with osseous or ligneous putamen, with one or 

 many monosnermous cells. The seeds enclose 

 an embryo without, or with a very thin, 

 albumen. They are trees or shrubs from all 

 warm regions of the globe. 



Zizyphus vulgaris. 



Yv. 



. 53. Long. sect, of 

 fruit 



Fis 



51. Long. sect, of flower. 



Fig. .52. Dried fruit. 



Fig. 50. Flower (f). 



Microrhamnus, a prickly shrub of Texas, with small ericoid leaves, 

 solitary flowers and an ovoid drupaceous finally dry fruit, with an 

 osseous monospermous putamen and basilar cupule, has been asso- 

 ciated with these ; but in our opinion it is only a species of Con- 

 dalia with the flower destitute of petals, an abnormal type (which 

 might strictly constitute a separate series) whose axillary flowers, 

 solitary or collected ill small cymes, have a receptacle in the form of 

 a hollow cup, lined with a thick flattened and pentagonal disk. The 

 corolla is almost always wanting, and the ovary is reduced to a single 

 cell into which a parietal placenta advances, forming an incomplete 

 partition on each side of which is an ascending ovule, with the 

 micropyle turned to the side of the placenta. The fruit is 

 drupaceous. The Condalias inhabit the warm and temperate regions 

 of the two Americas. 



