278 INSECTS AFFECTING VEGETATION 



The Canna Leaf-Roller. Leaves infested soon become so badly 

 eaten that they die, becoming brown and ragged, thus changing 

 them from beautiful ornamentals to unsightly objects. Those 

 having beds or terraces of cannas which have been dying, or brown- 

 ing, would do well to look for this insect in connection with the 

 trouble, and follow the treatment herein advised if it is observed to 

 be present. 



Leaves may either be rolled up from one side, by the larvae 

 or, as is more frequently the case, younger leaves are fastened, be- 

 fore they have unrolled to any extent. The caterpillars feed 

 within the rolled up leaves eating out the soft tissue to the epider 

 mis of the lower surface. Rarely is the epidermis of the lower 

 surface of the leaf eaten into, it being left usually quite intact. In 

 the case of younger unrolled leaves, the margin of the outer leaf 

 is firmly fastened to the roll by short silken threads. On the in- 

 terior leaves of the roll the larvae feed, usually quite consuming 

 the parenchymatous tissue within. In other cases, fully expanded 

 leaves are rolled up parallel to the mid-rib. This is done much 

 after the usual manner of leaf rolling larvae by spinning a thread 

 from the margin of the leaf to a point farther in toward the mid-rib. 

 Several of these cords are spun along the margin of the leaf and 

 by their subsequent contraction, the margin is pulled over, and 

 finally touches the leaf, thus forming a tube within which the Iarva3 

 feed. When the parenchyma within this tube is eaten out, the 

 leaf is rolled again, the larva coming out along the lateral margin of 

 the tube, and spinning threads from the tube to points yet nearer 

 the mid-rib. In this way a large canna leaf may be quite rolled up. 

 Usually but one or two larvae occupy a single leaf. However, as 

 many as five or six were found in a few cases. 



General color of larva, yellowish white; quite transparent, so 

 much so that in a live specimen the pulsation of the dorsal tube 

 may be easily observed. A greenish appearance is given to the 

 caterpillar from the green food within the alimentary canal. Head 

 yellow; clypeus, yellowish brown; tips of mandibles, brownish- 

 black. The adult is quite uniform light brown, varying in differ- 

 ent specimens to lighter; lines of brownish black extend across both 

 primaries and secondaries respectively one-third and two-thirds the 

 length of the wing distant from its base. A small angular patch of 

 white is found near the distal portion of the discal cell of the pri- 

 maries. The canna leaf-roller can doubtless be best controlled by 

 carefully cleaning off and burning the dead plants and trash from 

 the beds during the winter season. By this procedure, most of the 

 pupae and larvae, which pass the winter in these leaves and trash 

 will be destroyed. The rolled up leaves should be watched for in the 

 spring, and cut off and burned. (Bui. 45, Fla. Exp. Sta.) 



The Larger Canna Leaf-Roller. The parent is a large, skip- 

 per butterfly with a wing expanse of 1-1 ^ inches. The head is 

 very broad, with large eyes and the body is thick and heavy. The 

 upper surface of the head, thorax and a portion of the abdomen is 

 thickly covered with long, olive hairs. The wings are dark brown 



