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berries, Raspberries, Blackberries, Apples, Pears, 

 Quinces, Medlars, Plums, Cherries, Almonds, 

 Peaches, Apricots, etc. It has even been asserted 

 that no plant of this Order bears poisonous fruit, 

 and that any strange or unknown plant belonging 

 to it may be eaten with perfect safety. However, 

 many plants of this Order contain more or less 

 prussic acid in their pips and kernels, and often 

 in the flowers or leaves or other portions of the 

 plants ; and the fruit of the laurel is poisonous, 

 while bitter almonds contain a dangerous amount 

 of poison, and it is very imprudent to eat more 

 than a few kernels of any stone fruit, such as 

 cherries, plums, apricots, etc. 



The Roses generally have a 4- or 5-lobed calyx, 

 a corolla with as many petals, an ovary of several 

 carpels, and numerous stamens. Some are low- 

 growing plants, but a large number are bushes or 

 trees. The fruits differ much ; some are dry, and 

 others are succulent. The leaves are generally 

 pinnate, with serrated edges. The Order includes 

 about 2000 species, and is well represented in 

 most parts of the world. 



Blackthorn, or Sloe — Primus spinosa 

 (Plate XXIX) 



The Sloe, or Wild Plum, is a very common 

 bush or small tree in hedges and thickets, especially 

 on hill-sides. Its abundant white flowers appear 

 in early spring, generally before the leaves. 



The roots are very spreading, and throw up 

 numerous suckers ; the bark is rough, brownish 

 black, and frequently studded with strong thorns. 

 The leaves are smooth, lanceolate, and finely 

 dentated on the margins. The fruit is rather 

 smaller than a cherry. It is at first green, but 

 when it ripens in October the skin becomes purple, 

 and is covered with a bluish bloom. The pulp 

 has a very sour, astringent taste, and cannot be 

 regarded as edible. Within it is a hard stone, 

 containing the kernel or seed. 



Spring Cinquefoil — Potentilla verna 

 (Plate XXX) 

 This is a small plant which grows in dry hilly 

 districts, and flowers in April. The leaves are 



