Naturalisation in Extra-Tropical Countries. 369 



Pistacia vera, Linne.* 



Syria, Persia, Afghanistan. A deciduous tree, sometimes to 30 

 feet high, yielding the Pistacio-nuts of commerce, remarkable for 

 their green almond-tasted kernels. The galls from this tree are of 

 technic value. Dr. Bancroft adopted the ingenious plan of insert- 

 ing Pistacia-seeds into dry figs, to secure their power of germina- 

 tion during transmission to remote places. Artificial pollination 

 increases the fecundity. Can be grafted on P. Terebinthus [Parla- 

 tore, Dyer]. 



Pisum arvense, Linne. 



Eastern countries at the Mediterranean Sea. A good forage- 

 plant, though annual ; thriving in any soil ; best cut for stable- 

 fodder [Naudin]. Hardier and more drought-resisting than the 

 ordinary pea, of w^ich it may nevertheless be the origin [A. de 

 Candolle] . Alef eld, Koernicke and Wittmack, as leading scientific 

 agronomists, regard P. sativum as a garden- variety of this plant. 



Pisum sativum, Linne.* 



The common Pea. South-Western Asia. Cultivated already by 

 the ancient Greeks and Trojans [Virchow, Wittmack], during the 

 stone- age in Hungary [A. de Candolle]. Matures under horticul- 

 tural care seeds even in the hot desert-regions of Central Australia 

 [Rev. H. Keinpe], where it is a winter-plant like in tropical regions ; 

 on the other hand it comes to perfection as far north as 70 22' in 

 Norway [Schuebeler]. This annual of daily use could hardly be 

 left unnoticed on this occasion. Suffice it to say, that the herbage 

 as a nutritious fodder deserves more attention, than it receives. 

 The green fruit contains inosit- sugar and cholestrin-fat. For field- 

 culture a sandy-calcareous loam should be chosen for this plant, to 

 ensure rich and safe harvests. Peas retained their vitality after 

 four years' exposure to the extreme frosts of Polaris-Bay. P. 

 Aucheri (Jaubert and Spach), which is perennial, occurs in alpine 

 elevations on the Taurus. 



Pittosporum tenuifolium, Banks and Solander. 



New Zealand. This with P. eugenioides (Cunningham) has 

 proved very suitable for tall garden-hedges, for which these and 

 several other species were first brought into notice by the writer. 

 Unhurt by a cold of 9 F. [Gorlie]. Hardy at Campbelltown, 

 Argyleshire. P. Ralphii (Kirk), also from New Zealand, endures 

 the winters of Arran. Seeds of any Pittosporum hardly ever fail 

 to germinate. 



Pittosporum nndulatum, Yentenat. 



South-Eastern Australia. This tree with P. bicolor (Hooker) 

 produces a wood well adapted for turners' purposes ; to some extent 

 it serves also as a substitute for boxwood. The flowers furnish a 



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