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APOCYNACEiE. 



repeated once or twice at the interval of a day between. The brown scale can 

 only be got rid of by careful washing with sulphur and water. Some use soft 

 soap and water for washing off both the scale and bug ; but it is rather danger- 

 ous, as it is almost certain to injure the tender foliage wherever it touches them. 

 Oils will also destroy them readily, but that closes up the pores of the plants and 

 brings them into a sickly state so as to render them an easy prey to insects after- 

 wards. Sulphur put upon the flues or pipes will effectually destroy the red 

 spider. After the plants have been cleaned, the best preventive is to endeavour 

 to set the plants a-growing vigorously, as few insects will breed naturally upon a 

 healthy-growing plant. Ants and woodlice are also sometimes troublesome" in 

 hothouses : the best preventive for these is to keep two or three toads in the 

 house, which will destroy them readily ; but the toads must have access to a damp 

 and shaded situation during the heat of the day. They will also devour slugs ; 

 but these may be picked off the plants in the evening by candle-light. 



APOCYNACEJ3. 



Among the various orders of plants into which the vegetable kingdom is 

 divided, there are very few that are entitled to more attention than the Apocy- 

 nacese. The order, as understood by modern botanists, comprises about seventy 

 genera, many of which are no less interesting to the naturalist than they are 

 important to the medical man. They are chiefly natives of Africa, tropical India, 

 and the equinoxial parts of America : two only are natives of Great Britain, 

 Vinca major and minor, the greater and lesser Periwinkle. As regards their 

 properties, they vary considerably, some being valuable for their febrifugal quali- 

 ties ; some for their emetic and cathartic properties ; while others contain the 

 most deadly poisons : indeed all the plants of this family should be regarded as 

 exceedingly suspicious. 



The essential character of the order is thus given by Dr. Lindley ; — -" Calyx 

 divided into 5, persistent. Corolla monopetalous, hypogynous, regular, 5-lobed 

 with contorted aestivation, deciduous. Stamens 5, arising from the corolla, with 

 whose segments they are alternate. Filaments distinct. Anthers 2-celled, open- 

 ing lengthwise. Pollen granular, globose, or 3-lobed, immediately applied to the 

 stigma. Ovaries 2, or 1, 2-celled, polyspermous. Styles 2 or 1. Stigma 1. Fruit 

 a follicle, capsule, or drupe or berry, double or single. Seeds with fleshy or carti- 

 laginous albumen ; testa simple ; embryo foliaceous ; plumule inconspicuous ; radicle 

 turned towards the hilum. Trees or shrubs, usually milky. Leaves opposite, 

 sometimes whorled, seldom scattered, quite entire, often having cilise or glands 

 upon the petioles, but with no stipules. Inflorescence tending to corymbose." 



The plants of this order all agree in the above essential points of character, 

 the genus Apocynum (Dog's Bane) having been selected as the type. Apocynum 



