EXPERIMENT STATION BULLETINS. 



209 



GREENHOUSE LEAF-TYEE. 



{Phlyctaenia ruligalis.) 



A small Tiniid larvae or green "worm" that feeds on the leaves of greenhouse and forc- 

 ing-house plants, tying them together into nests. 



This destructive creature lias already appeared in several widely sep- 

 arated greenhouses in Michigan, and, no doubt, will appear in others. 

 It feeds on a long list of greenhouse and forcing-house plants. Pro- 

 fessor M. V. Slingerland records it on most soft-leaved greenhouse 

 plants, especially on lettuce, sweet-peas, clover, parsley, cinerarias, chrys- 

 anthennuns, geraniums, strawberries and cucumbers. Others record its 

 work on tobacco (in hot-bed), carnations and violets. In our state the 

 most injury has been done to chrysanthemums, although many other 

 plants have been attacked. 



When sitting on the plants, the moths present a triangular outline, 

 the wings being raised slightly along the middle line. The color is 

 yellowish-brown with a tinge of rust, the front-wings being darker than 

 the hind-wings and marked by inconspicuous darker, transverse, wavy 

 lines. The moth is a little less than half an inch in length. 



Fig. 6. Adult of greenhouse Leaf-tyer, after Slingerland; natural size in center below. 



The eggs are oval and flat, greenish-golden in color and opalescent. 

 They are usually laid close together in small clusters. The larvae are 

 about five-eighths of an inch in length, very lively, and in color, green. 

 They are marked by three longitudinal stripes, a darker green one along 

 the middle of the back, and a lighter stripe on each side of the median 

 one. 



The damage is wrought by the larvae which eat the tissue in patches, 

 usually from the underside of the leaves, leaving the skin on the upper 

 surface intact. In thin leaves, like lettuce, they are said to devour 

 the entire leaf. As the larvae grow, they bind together and curl some 

 of the leaves, more often the smaller ones, making nests in which they 

 change to pupae, inside of small white cocoons. Professor Slingerland.* 

 in his exhaustive discussion of this creature, savs that seven or eight 



♦ Bulletin 190 Cornell University Experiment Station. 

 27 



