FEB.] THE HOT-HOUSE. 183 



D arrow in proportion to their length, and cross one another at some 

 distance from their base; feet six, the tarsus of each foot having 

 only two articulations. 



This is also a very pernicious species of insect, and is very com- 

 mon in hot-houses, as well as upon plants in the open air ; it is very 

 minute, so much so as to be scarcely perceptible, generally concealing 

 itself along the veins of the leaves, from whence it skips with great 

 agility on being touched. It is a great enemy to the vine while the 

 leaves are young and tender, whether they grow in the open air or 

 under glass. The Cape jasmine, as well as many other plants, often 

 falls a prey to these minute insects. 



These may be destroyed by the same methods as the Aphis. 



4. The ONISCUS, or Wood-louse. This belongs to the order AP- 

 TERA. Characters: Antennae setaceous, and bent-mouth, furnished 

 with two palpi; head intimately joined with the thorax; body oval 

 form, composed of several crustaceous plates ; feet fourteen. They 

 change their skin like many other apterous insects. 



These are very common in the bark-pits, as well as in woods, 

 houses, gardens, &c., but are seldom destructive except to young 

 seedling plants on their first appearance above ground. This, how- 

 ever, may be prevented by dusting the plants, whilst in that state, 

 with fine snuff or tobacco dust. 



5. The FORMICA, or Ant. This insect is so universally known as 

 to render a description unnecessary. 



These are often exceedingly numerous in hot-houses, and especially 

 where the Aphides and Coccus hesperidum abound, for there is a 

 sweet glutinous matter which issues from these insects (being either 

 their excrements or produced by them from some other cause) that 

 seems to be the principal incitement that draws the ant thither. 



The ant may be destroyed with great facility by setting pots con- 

 taining honey and water in the same manner as is practised for 

 catching wasps, &c. 



6. The Coccus HESPERIDUM, or Brown Turtle Insect, already de- 

 scribed, is not only an enemy to the pine-apple plant but also to 

 many others both in the hot-house and green-house, therefore I am 

 induced to take notice of it again. 



This insect may be destroyed whilst young by fumigation, there- 

 fore, where that operation is frequent, they are rarely to be met with. 



OP FUMIGATING THE HOUSE. 



The house may be fumigated either by means of bellows invented 

 for that purpose or by that of a smoking-pot. The most eligible 

 seasons for this business are the spring and autumn, when, if neces- 

 sity requires, it should be repeated every eight or ten days, till the 

 proper effect is produced ; but it may be done at any period, except 

 when there are ripe fruit in the house, as then it would give them a 

 smoky flavor. 



Fumigation is best performed late in an afternoon or evening, and 

 proves most efficacious whan the weather is moist and calm ; for the 

 smoke is retained much longer in the house when the air is still and 



