SNAILS. 



472 



SOILS AND COMPOSTS. 



Geraniums are much the same, but vary in height, 

 Tom Thumb, and others of the same class, are of 

 dwarf habit. The Zonale, or horseshoe-leaved, 

 are mostly of tall habit ; Cerise and pink- 

 flowering sorts are generally dwarf. 



Heliotropes are mostly of lilac colour, but some 

 are darker : they are mostly dwarf and spread- 

 ing ; but they are chiefly valued for their per- 

 fume. 



Lantanas are much the same in habit, growing 

 about 15 inches high. 



Lobelias, which are mostly blue, are all of very 

 dwarf habit, and are very effective for frontage, 

 being continuous bloomers. 



Petunias are much the same in habit as verbenas, 

 being dwarf and trailing : this tribe embraces 

 many colours. 



Verbenas are very much of the same habit and 

 height ; but a very fine effect is produced by 

 planting beds entirely with them, they combining 

 all colours but yellow. 



Snails. 



To prevent snails crawling up walls and 

 trees, they must be looked for, picked off 

 by the hand, and killed. If a thick paste 

 be made with train oil and soot, and 

 the bottom of the wall daubed with it, an 

 effectual barrier will be formed over which 

 no snails will attempt to pass. 



Snowdrop. 



This is one of the most elegant and 

 interesting of spring flowers : it may be 

 had in bloom indoors at a very early 

 period ; its white blossoms contrasting 

 beautifully with the rich hue of the crocus, 

 &c. A row of snowdrops is often very 

 effective in juxtaposition with a row of 

 blue crocuses. October is the best month 

 for procuring and planting them, although 

 they may be inserted much later. There 

 are many varieties of this beautiful bulb, 

 but Elwesii, or Giant Snowdrop, is most 

 effective and valuable for pot culture in- 

 doors. 



Snow'flake. See Leucojum. 



Soils and Composts, Harvest- 

 ing of. 



All who have examined this question 

 admit that the value of manures is in 



proportion to the nitrogen or phosphates 

 which they contain, more especially the 

 former ; for nitrogen is almost synonymous 

 with ammonia, that being the chief source 

 of nitrogen for plants. " Let the cultiva- 

 tor," says Dr. Scoffern, " take care of his 

 ammonia ; let him take care of his phos- 

 phates ; let him prevent the loss of all 

 soluble matters from his compost-heap." 



The first and most important source of 

 these elements is farmyard manure, which, 

 in its fresh state, consists of the refuse of 

 straw, of green vegetable matter, and the 

 excreta of domestic animals. Horse dung 

 varies in its composition according to the 



food of the animal ; it is most valuable 

 when they are fed upon grain, being then 

 firm in consistence and rich in phosphates. 

 Sheep litter is a very active manure, and 

 rich in sulphur and nitrogen ; for if a slip 

 of white paper, previously dipped in a 

 solution of lead, be exposed to the fumes 

 of fresh sheep dung, the paper will be 

 blackened ; a sure test of the presence of 

 sulphur. 



Cow Ikter is cooler, and less rich in 

 nitrogenous or azotised matter ; but it is 

 rich in salts of potash and soda, and thus 

 better adapted for delicate and deep-rooted 

 plants. Swine's dung is still less azotised 



