138 INSECTS AFFECTING THE ORANGE. 



Life-history. The eggs are spherical, smooth and pearly in luster, 

 with a dull red or reddish-yellow tinge, and are deposited singly, inva- 

 riably upon the youngest and most tender shoots, usually upon the tips 

 of the budding leaves (Plate XI, Fig. 1). The butterflies appear with 

 the opening of spring from chrysalids formed in November and Decem- 

 ber. The first eggs are deposited early in February, or as soon as the 

 new growth appears upon the orange trees. The eggs hatch in ten or 

 twelve days. The caterpillar completes its growth in about thirty days, 

 and remains in pupa from ten to fifteen days. About two months is 

 thus occupied by a single brood, and there are four full broods during 

 the season beginning with February and ending with October. The 

 breeding is, however, continuous during the summer, and eggs are laid 

 whenever new growth appears upon the orange trees. 



The ovaries contain over five hundred eggs, the laying of which occu- 

 pies the female many days j she scatters them over a wide area, seldom 

 depositing more than four or five upon a single plant. The young 

 caterpillars feed at first only upon the tenderest leaves, but when well 

 grown demolish both leaves and shoots which have not hardened into 

 wood. 



On account of its large size and voracity, the Orange Dog does great 

 damage, particularly to young trees, which are sometimes completely 

 defoliated. It has other food plants besides the Orange; among the 

 number the species of Prickly Ash (Zanihoxylum) are mentioned by 

 several authors. It is found commonly in the swamps of Florida, feed- 

 ing upon the Tupelo (Nyssa aquatica, L.) and upon the Eed Bay (Persea 

 carolinensiSj Nees). It seems, however, to prefer the Orange and its 

 relatives to all other plants. 



Defensive measures. Hand-picking is not a very difficult task in the 

 case of so large an insect, and must in most cases be relied upon to 

 keep young trees free from Orange Dogs. As the eggs are quite large, 

 and conspicuously placed.at the tips of the growing stalks and budding 

 leaves, it is a simple matter to find and pinch them between the fingers. 

 A very little practice will enable the orange grower to go rapidly 

 through his young grove and destroy by hand nearly every egg. If 

 this method is systematically pursued, the result will well repay the 

 trouble. Two rules should be borne in mind, and will greatly facilitate 

 the work. (1.) Only those trees which are pushing out tender sprouts 

 need be examined for eggs and young larvae.* (2.) In nearly all cases 

 the eggs are laid upon sprouts at the top of the young tree and not 

 upon those low down and near the ground. 



* While this rule in regard to the disposition of the egg can be predicated with 

 great confidence for the orange district of Florida, it is but just to observe that it 

 may not hold good for Louisiana and other more northern localities. Mr. L. O. How- 

 ard has in fact found the eggs of Papilio crespliontes upon the older leaves, and on the 

 twigs of orange trees, growing in public parks in the city of Savannah, Ga. The 

 observation was made about the middle of August. 



