hard to determine what is the primary cause of trouble in both eases, 
and this disease is to-day less understood by the most practical men in 
the business than any other disease peculiar to the Rose. Since the 
causes from which it emanates is so badly understood, it is of course 
equally difficult to suggest a remedy. When grown in greenhouses, the 
best means of checking the disease we have found is a healthy, dry 
atmosphere at night and a free circulation of air during the day, with a 
little fire heat to counteract any cold draughts. Where Roses are in- 
fested with Black Spot in the open ground, the best remedy is to cut 
the plants back and remove all leaves infested; when it starts to grow 
again the chances are that the Black Spot will not appear. 
ROSE HOPPER. 
This is another troublesome pest with which the Rose is afflicted in 
the open ground. It is a small yellowish white insect about three- 
twentieths of an inch long, with transparent wings. Like the Red 
Spider they prey upon the leaves, working on the under side. They 
go in swarms, and are very destructive to the plant. As they jump and 
fly from one place to another, their destruction is less easy to accom- 
plish than is the case with other enemies. Syringing the plants with 
pure water, so as to wet the under side of the leaf, and then dusting on 
powdered hellebore or tobacco dust, will destroy or disperse them. 
ROSE CATERPILLAR. 
These are the young moths or butterflies, varying from one-half to 
three-quarters of an inch in length. Some are green and yellow, others 
brown. They all envelop themselves in the leaves or burrow in the 
flower buds. Powdered hellebore will prevent in a large measure their 
moving over the plants, but the only method of killing them that is 
really effective is picking them off with the finger and thumb and 
tramping them under foot. 
ROSE SLUG. 
These slugs are the larva of a saw-fly, about the size of a common 
house-fly, which comes out of the ground during May and June. The 
female flies puncture the leaves in different places, depositing their eggs 
in each incision made; these eggs hatch in twelve or fifteen days after 
they are laid. The Slugs at once commence to eat the leaves, and soon 
make great inroads upon the foliage if not checked. They are about 
one-half an inch long when fully grown, of a green color, and feed upon 
the upper portion of the foliage. The best remedies are powdered white 
hellebore, or a solution of whale oil soap. 
CLEANLINESS. 
\\ e have given a list of remedies for controlling the ravages of 
the various pests which worry the Rose, and would remind our 
readers that prevention is better than cure. Cleanliness, a pure 
