198 THE MONTHLY BULLETIN. 



the liead. which exhales a very pungent and characteristic odor. The 

 eggs are about 1 mm. in length, at first yellow and later reddish brown 

 in color, and flattened at the attached end. The adult butterflies are 

 commonly known as tlie black swallowtails, being black with yellow 

 markings. The chrysalids vary from green to dull gray and are more 

 or less mottled. 



Life History. — The eggs are laid upon the food plants from spring 

 to early summer and hatch in about ten days. The caterpillars are 

 voracious feeders and develop very rapidly, being ready to form chrysa- 

 lids in about one month after hatching. Chrysalids hatch in about two 

 weeks. The adults being strong fliers are able to scatter their broods 

 over large areas. There are several generations a year. 



Distribution. — The caterpillars are to be found in nearly every gar- 

 den in the State. This is especially true of the central part. 



Food Plants. — In many localities this caterpillar is a serious pest of 

 celery and parsley, but feeds also upon carrots, caraway, parsnips, dill, 

 fennel and related wild plants. 



Control. — Though the caterpillars may be controlled by poison 

 sprays on some crops, these are not safe for celery and parsley. The 

 larvffi are so conspicuous as to make hand picking one of the best meth- 

 ods of control. If care is exercised to collect and destroy the first 

 larvffi the second and more damaging brood will be greatly reduced. 

 Concerted action on the part of all growers is necessary to bring satis- 

 factory results. 



Natural Enemies. — The ichneumon parasites, Trogus vulpimis Grav. 

 and T. cxidianator Brulle, destroy great numbers of the chrysalids. 



THE CALIFORNIA ORANGE DOG. 



Papilio zoJuMOH Boisd. (Family rapilionidie. ) 



General Appearance. — The adult butterfly is one of the smaller swal- 

 low-tails Jiaving a wing expanse of from two to three and one half 

 inches. The color is black and orange-yellow, each being about equal 

 in extent — the yellow being distributed along the edges and in the 

 middle of the wings. 



Life History. — The eggs are laid singly upon the lower surfaces of 

 the leaves, there being from five to seven on a tree. Upon hatching the 

 larva; at once begin to feed upon the foliage. Development is rapid. 

 The chrysalids are found in sheltered places and form the over-winter- 

 ing stage. The adults appear early in the spring. 



Distribution. — One of the most widelj^ distributed species, being espe- 

 cially abundant in Tulare County, in the San Joaquin Valley and other 

 parts of the State. 



Food Plants. — The natural food plants of this insect are various 

 species of IJmhelliferce, the most favored ones being Fmnculvm vulgare 



