AMERICAN INSTITUTE- 291 



couple of hour's ride of each other. Cotton, cabbages, sugar, 

 potatoes, dahlias, buckwheat, rice, cheremoya, fig, orange, clover 

 and timothy, and southern crab grass, rye and wheat, fuchsias and 

 a tliousand flowers of both zones, can be found every morning in 

 the same market fresh from the gardens above and below. And 

 the animals also are here of far distant districts; the splendid 

 shawl goat may live above, while our sheep lives in the valley 

 below. 



[Revue Horticole, Paris, September, 1856.] 



INSECTS. 



Of the whole animal kingdom, the knowledge of insects is most 

 important to horticulture. Their vast numbers, their small dimen- 

 sions, the great difficulty in making accurate observations of their 

 characters and manners, the extent of the injury caused by cer- 

 .tain species and the- important services rendered to us by others, 

 all these demonstrate abundantly the great utility of the study of 

 entomology. The Insects dire(?tly useful to man are reduced 

 pretty nearly to three — the Cochineal, the Bee and the Silk-worm. 



Insects almost supply the place of the thermometer, so precisely 

 are their appearance governed by temperature, and their coinci- 

 dence with, the plants necessary to them. With this idea. Prof. 

 Boyle has established in the environs of Aix, in Provence, an 

 entomological and botanical calendar, or table of the first appear- 

 ance of principal insects with the first flowering of indigenous 

 vegetables. See Mons. Quetelet's observations in vol. 21, of the 

 Annals of the Belgian Academy. 



Some false notions are entertained as to the effect of tempera- 

 ture on the insects. It is generally believed that very cold 

 winters hinder their development, yet these little beings sustain 

 very low temperature without inconvenience. Mons. Mathieu, 

 Professor of the school of forests, has observed that the eggs of 

 lepidopter£e exposed to a cold of about 40° centigrade, (or about 

 20 degrees below zero of Fahrenheit,) were not injured. Cater- 

 pillars and their chrysales were not killed at 50*^ when they were 

 all ice and gave a sound when dropped, and all revived when the 

 suitable temperature returned; and on the other hand they sustain 

 very high heat, even that of very hot water. Gnats frozen in ice 

 remain so a long time without loss of vitality. 



