56 



CHERRY. 



covering the eggs were about one- sixteenth of an inch across, 

 and on one leaf, where I counted them, over thirty in number ; 

 on another there were about twenty-five ; all these (with 

 possibly one exception) showing on the upper surface of the 

 leaf.* 



Shortly after hatching, the grubs — which at first are white, 

 afterwards yellowish — become covered with a blackish or dark 

 greenish secretion, from which, and their lumpy shape (see 

 figure, p. 54), they receive their name of slugworm. When 

 carefully examined, they will be found to be much the thickest 

 at the fore part of the body, and to have twenty-two pairs of 

 feet, — that is, three pairs of claw-feet on the three segments 

 next the head, none on the fourth segment, and all the rest 

 of the segments furnished with a pair of sucker-feet. The 

 pair on the the terminal segment are, however, so small that 

 sometimes they have been overlooked, or not considered to 

 exist, and the larva classed as twenty-footed. 



When full-grown, which is in five or six weeks, the slug- 

 worms are about five-eighths or half an inch long, and they 

 then cast their bottle-green smooth coats, and appear as buff 

 caterpillars, dry and free from all slime or shininess, and, 

 instead of being smooth, transversely wrinkled. After this 

 the caterpillars go down into the ground, where they spin an 

 oval dark-coloured or black silken cocoon, probably covered 

 outside with earth, from which the sawflies come out some 

 time in the summer of the following year. The earliest date 

 at which I am aware of having received specimens of the 

 attack is the 14th of June, and the attack may continue till 

 October. 



The destructive work of the caterpillars can be at times 

 very rapid and complete. In a note of attack sent me 

 from Worcestershire, a large Pear tree was noted as being 

 stripped almost completely of its leafage in four days from 

 the date of first observation, the leaves dying and drying from 

 the skin of the upper side being eaten off. Somewhat earlier 

 in the same year, — that is, on the 8th of July, 1896, — speci- 

 mens were sent me of caterpillars said to be devastating the 

 fruit trees in a garden in North Devon; "Cherry trees 

 especinllv, a large one in a week was just a skeleton." 



The upper surface of the leaf is removed sometimes wholly, 

 sometimes in patches ; but the method of destruction, that is, 

 the attack being to the upper side of the leaf, and the rest 

 being left as the net-work of veins and thin lower skin beneath 

 them, is characteristic of the attack. 



With us, the damage is mostly observed as affecting Cherry 



* See 'Seventeenth Eeport on Injurious Insects,' by E. A. Oimerod, p. 81. 



