5'JO summary of current researches relating to 



BOTANY. 



GENERAL, 



Including the Anatomy and Physiology of Seed Plants. 



Structure and Development. 



"Veg-etative. 



Anatomical Study of the Mangiferese.* — M. A. Goris publishes a 

 contribution to the systematics of this tribe of Anacardiaceae, based upon 

 anatomical characters. Referring to the previous work of Jadin, the 

 author finds that the leaf (always simple), rather than the stem, is im- 

 portant for the diagnosis of genera. 



The tribe includes the following genera, grouped in accordance with 

 floral characters : — 



A. Five free carpels, only one fertile . . . Buchanania. 



B. One carpel only. 



(«) Leaves alternate. 



i. Stamens 10-5, 4-1 fertile, the others 

 aborted. 



1. Pedicel swollen under the fruit . Anacardium. 



2. Pedicel not swollen under the fruit Mangifera. 

 ii. Stamens 3, all fertile ; drupe globular, 



ovoid. 



1. Petals sessile, not accrescent . Gluta. 



2. Petals accrescent under the fruit Swintonia. 

 iii. Stamens numerous ; petals accrescent . Melanorrhea. 



(b) Leaves opposite ..... Bourn. 



The anatomical structure of all these is essentially of one type, the 

 diffeiences being secondary only, but of value in differentiating the 

 genera. This anatomical grouping, moreover, is in accord with that 

 based on floral characters. Buchanania is characterized by the presence 

 of mucilage in the cells of the leaf -epidermis, which are of a peculiar 

 form. The stem differs from that of the other genera in the smallness 

 of the amount of cortical sclerenchyma, and the presence of bast-fibres, 

 which divide the bast into several zones. Swintonia is readily dis- 

 tinguished by the papillae which occur on the leaf -epidermis. The shape 

 and structure of the leaf suggest affinity with Buchanania, the two being 

 isolated from the rest of the tribe. Anacardium differs from the other 

 genera in having secretory canals in the cortex of stem and leaf-petiole. 

 The arrangement of the stomata is also characteristic. Bouea is dis- 

 tinguished by the presence of sclerotic cells in the mesophyll, the 

 absence of secretory canals in the pith, and the arrangement of the 

 vascular bundles in the petiole and main vein, which tend to remain 



* Ann. Sci. Nat. Bot., xi. (1910) pp. 1-29 (figs.). 



