ORDER MONADELPHIA. 265 



The Wild-turnip (Arum), is nearly allied to the Calla ; they 

 belong to the family Aroides, which are distinguished by pecu- 

 liar characteristics ; such as their mode of inflorescence, 

 fleshy and tuberous roots, and large, sword-shaped or arrow- 

 shaped leaves. 



The arrow-head (Sagittaria), is unlike most of the Monoe- 

 cious plants in general appearance ; it has a three leaved calyx 

 and three white petals, and is not unlike the Spider's-wort in 

 the form of its flowers. Many species of this very delicate 

 looking plant may be found in autumn, in ditches and stagnant 

 waters. 



Monadelphia. 



The 15th order, in which the filaments are united in a 

 column, presents us with the Cucumber tribe (Cucurlitacecz) ; 

 these include not only the proper CUCUMIS, which is an exotic, 

 but some native genera, of similar plants ; we find here the 

 gourd, squash, watermelon, and pumpkin. These plants have 

 mostly a yellow, 5 cleft corolla, calyx 5 parted, 3 filaments 

 united into a tube, a large berry-like fruit, called a Pepo ; this, 

 in the melon, is ribbed, and in the cucumber uneven and warty. 

 We find in the same artificial order a very different family of 

 plants, called Coniferous, or cone bearing plants ; these have 

 the staminate flowers in aments, each furnished with a scale or 

 perianth supporting the stamens ; the pistillate flowers are in 

 strobilums, each furnished with a hard scale. The stems are 

 woody, the leaves evergreen, and the juice resinous. To this 

 natural family belong the pine and cypress. 



The character of trees may be studied to advantage at four 

 different seasons : in winter, when the forms of the ramification 

 can be seen in the naked boughs, and the leaf and flower buds 

 examined in their inert state ; in spring, when in blossom ; in 

 summer, when the foliage is in perfection ; and in autumn, 

 when, during the first stages of decay, the mellowness and 

 variety of tints afford beautiful subjects for the pencil of the 

 painter, and the investigation of those who love the study of 

 nature under all her forms. 



Aroides Arrow-head Order Monadelphia Cucumber tribe General cha- 

 raeter Cone-bearing plants Best periods for studying trees. 



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