THE FLORAL WORLD AND GARDEN GUIDE. 295 



late— and placing them in a frame well exposed to the sun and 

 never shaded, and watering them as freely as you would a geranium, 

 never taking the lights oft', and giving a medium degree of ventilation, 

 and taking no notice of how much the frame gets above 100" on very 

 hot days, you may grow them very well indeed — quite superior to 

 those seen in a greenhouse. Let the glass of the frame be as clear 

 and large as may be, and never shade it. In many gardens where 

 there are pits and the like empty, or nearly so, during the summer 

 months — perhaps full of slightly-heated material — they might be 

 grown to perfection, and in any case it would require very little 

 trouble to prepare a place for them. They should be placed as near 

 the glass as possible, and taken into the warm greenhouse or sitting- 

 room early in autumn, and there are no plants in existence that 

 winter better in a dry, airy, and warm room. The sloppy, dull 

 character of many greenhouses is very prejudicial to these natives 

 of sunny climes ; they feel ns miserable in it as their countrymen 

 would in a "good" specimen of a cold Loudon fog. My friend, 

 Mr. John O'Brien, who planted and developed the grand tropical 

 fernery at Rockville, near Dublin, and who made that place what it 

 is during his superintendence, afterwards wrote from Mexico, the 

 country from which hundreds of these plants come, to say that 

 though frost is occasionally present there, and he found ice thick 

 in the bases of the Agave leaves, and Ladias flourish tipped with 

 hoar frost, yet the climate is of the most brisk and sunny character, 

 the air bright and warm, and so clear that you may sometimes trace 

 " a thin column of smoke rising a mile in the air." Is it any wonder 

 that Mexican Mammillarias, placed at some distance from the glass, 

 and perhaps shaded by tall-growing plants, should not succeed under 

 such circumstances ? How they have continued to exist at all is 

 the wonder, considering the lot of nonsense that has been written 

 about keeping them dry and feeding them with broken bricks. They 

 flourish beautifully in compost suitable for a show geranium, or, 

 indeed, in almost any ordinary potting-shed soil. It is the light 

 and the brisk temperature during the summer that are required. 



As regards the winter treatment, there is a fallacy current that 

 often causes the death of a rare kind, and that is that they do not 

 require water for six or seven months of the year. Many a gardener 

 would anathematize his young men for watering them later than 

 October or earlier than the end of March, whereas, if kept in the 

 right temperature, they enjoy au occasional dose of water all the year 

 round. There is not the slightest occasion for keepiug them a whit 

 drier than a good show geranium grower keeps his plants during the 

 dull weeks of mid-winter. But they must be kept in a dry warm 

 greenhouse, and in the warmer part of it, near the glass. Cold, or hard 

 frost is fatal to a great many species. They rot off after a degree of 

 cold which New Holland plants bear with impunity, and should as a 

 rule never be kept in a house where the temperature sinks below the 

 freezing-point, or, to be on the healthful side, say 40°. I have seen 

 many rare kiuds, including the beautiful Mammillaria senilis, killed 

 by frost. By the way, that is a kind which Sigma, who knows so 

 well how to grow it, should possess. Nothing can exceed the beauty 



