132 



THE GYPSY MOTH. 



light, would trickle down to the edge and hang there, form- 

 ing an impassable obstacle to the caterpillars. The intent 

 of the lime bands used in the work on the gypsy moth was 

 to prevent any caterpillars from ascending the trees. If a 

 few reached the branches and remained in the trees, passed 

 through their transformations and laid their eggs, it is obvious 

 that the bands would be worthless for the purpose for which 

 they were intended, though even then they might be useful 

 in controlling certain other caterpillars which frequently 

 spin or drop to the ground, as they would prevent most of 

 them from reascending the tree. But in a case where exter- 

 mination is sought, and destruction of all gypsy caterpillars 

 is a consequent necessity, it is imperative to prevent their 

 ascending large trees. Quite frequently the bands were 

 injured or displaced in some way by people or animals 

 brushing against them, and often leaves or twigs fi'om the 

 trees dropped and stuck upon the bands, forming bridges over 

 which the caterpillars could climb. To lessen the chances of 

 their reaching the branches, two or even three bands were 

 sometimes put upon the same trunk, one above the other.* 

 The same thing has been done in Germany during great 

 invasions of the nun moth (^Lijparis monacha), and for this 

 purpose a machine has been devised for applying insect lime 

 at a greater height on trees than could be otherwis reached 

 by hand from the ground. 



The Hochleim machine (Plate XXL, Fig. l)t is a tin 

 cylinder attached to a long pole. A top that acts as a plunger 

 is fitted to the cylinder and may be depressed by pulling on 

 a cord that is fastened to a strong spiral spring. This spring 

 is connected with iron wires which are attached to the upper 

 part of the machine. When this is depressed, the lime is 

 forced out at the bottom of the machine through a round hole 

 bored in a brush which is fastened to one side, as seen in the 

 figure. The lime, which must necessarily be of a more or 

 less liquid consistency, is applied around the trunk of the 



* This would not be ordinarily necessary in protecting trees against attacks of 

 native caterpillars. 



t Figures of the implements and machines appearing on plates XXI. and XXII. 

 have been previously published, together with others, in "Die Nonne," b}" Dr. H. 

 Nitsche, Ed. Holzel's Verlag, Vienna, 1892. 



