170 FERNS IN THEIR HOMES AND OURS. 



The mealy-bug (Coccus, PI. 22, Fig. 6) is sel- 

 dom found in the fern-house, as the dampness 

 required for the health of the ferns is too great 

 for its well-being ; and as the males are winged, 

 and are destroyed by smoke, the females seldom 

 increase sufficiently to do any harm. Should they, 

 however, become troublesome, a smart syringing 

 will usually dislodge most of them : the rest can 

 be destroyed by a small stiff brush or little pine 

 stick. Kerosene is frequently recommended for 

 killing the mealy-bug ; but, in the hands of a be- 

 ginner, it is a dangerous remedy. 



The various scale-lice (Lecanium and Aspidio- 

 tus) are usually found on the stipes and rachis of 

 the fern. They cannot be made to relinquish 

 their hold by any such mild treatment as will dis- 

 pose of the mealy-bug. It will generally be found 

 necessary to remove each plant attacked to some 

 suitable place, out of doors if possible, where the 

 f scale-lice must be carefully removed either with 

 a little stick or the finger-nail. The plant must 

 afterward be washed with soap and water, to re- 

 move any eggs that may adhere to it. Dr. Pack- 

 ard speaks of several species of these insects 

 which have attacked the plants in the Amherst 

 and Cambridge greenhouses. The Lecanium fil- 

 icum preys on the strong-growing ferns. It is 

 shown, highly magnified, in PI. 22, Fig. 8, as 

 seen from above, and in Fig. 7 from underneath, 



