Naturalisation in Extra-Tropical Countries. 365 



Pennisetum villosum, R. Brown. 



Abyssinia. A grass of decorative beauty, forming ample tufts ; 

 it is recommended by Dr. Curl for permanent pasture in New Zealand. 

 With numerous other grasses it was introduced into Australia by the 

 writer of this work. Proves fruitful in Norway to lat. 67 56' 

 [Schuebeler] . 



Pentzia virgata, Lessing. 



South-Africa. A small cushion-like bush, recommended for estab- 

 lishment in deserts for sheep-fodder. It has the peculiarity, that 

 whenever a branch touches the ground, it strikes roots and forms a 

 new plant ; this enables the species to cover ground rapidly [Sir 

 Samuel Wilson]. Valuable also for fixing drift-sand in water-rills, 

 by readily bending over and rooting, thus forming natural little catch- 

 dams to retain water [MacOwan]. Mutton from sheep depasturing 

 on this plant proves particularly palatable. Several other species 

 occur in South- Africa. Systematically these plants are allied to the 

 Tansy. 



Periandra dulcis, Martius. 



Sub-tropical Brazil. The sweet root of this shrub yields a kind 

 of liquorice. 



Perilla arguta, Bentham. 



Japan. An annual herb. An infusion of this plant is used for 

 imparting a deep-red colour to table-vegetables and other substances. 

 In Japan the seeds are pressed for oil. P. ocimoides, L., of Upper 

 India, probably serves similar purposes. Some species of Perilla are 

 suitable for ribbon-culture. P. Nankinensis affords its aromatic 

 flowers as a condiment in China and Japan. 



Persea gratissima, Gaertner. 



The Avocado -Pear or rather "Agtiacate," called in Peru "Palta." 

 From Mexico to Peru and Brazil in forest-tracts near the coast ; but 

 its real nativity, according to A. de Candolle, restricted to Mexico. 

 A noble evergreen spreading tree. Adverse to drought ; likes humid 

 soil. Suggestively mentioned here as probably available for mild 

 localities outside the tropics, inasmuch as it has become naturalised in 

 Madeira, the Azores and Canary Islands. The fruit attains some- 

 times a weight of 2 Ibs., and is generally sliced for salad, and of 

 delicious taste and flavor. Its pulp contains about 8 per cent, of 

 greenish oil. In Jamaica it is cultivated up to 4,000 feet [W. Faw- 

 cett]. It matured in littoral Eastern Australia, somewhat outside the 

 tropics [Edgar]. It also ripened its fruit abundantly near Moreton- 

 Bay. Lives unprotected as far south as Port Jackson [C. Moore]. 

 The seeds have come into medicinal use at the instance of Dr. 

 Froehling, particularly through the efforts of Messrs Parke and 

 and Davis, to whom we mainly owe the recent introduction of many 

 other valuable new drugs into medicine. 



