38 



THE TOMATO WORM PARASITE. 



was on sale here May ist, and the new celery was 

 ready early in July. But the bulk of the crop is 

 sold out by New Years. This season it has brought 

 the producers 12 to 15 cents per dozen, and upwards 

 for extra fine. 



One of our Hollanders places the value of the 

 three crops produced each season upon one acre at 

 ^600, and this at the average prices of the last three 

 years. Much more was realized during the early 

 days of celery culture in this place. The profits of 

 celery raising are like the profits of many other 

 forms of gardening, largely dependent upon the cir- 

 cumstances of the gardener, and while the patient 

 and laborious Hollander has by the untiring labor 

 of himself, wife and children attained enough of this 

 world's goods, in many cases, to retire from active 

 labor, many of our speculators have discovered to 

 their sorrow that unskilled, greedy push, and knowl- 



edge of the common ways of the world of grab, are 

 no match in the celer)' garden for skillful and patient 

 industry. And even these are not always success- 

 ful, as was shown by the results of severe frosts on 

 May 2gth and September 30th last. These did great 

 damage, and in many cases spoiled whole fields. 

 But such unseasonable visitations are out of the 

 common order of things, and there is no reason to 

 fear but that Kalamazoo celery will continue to 

 "wave in the breeze," and delight the palates of 

 our neighbors both near-by and afar-off. Neverthe- 

 less, careful estimates of the loss by the late frost 

 makes it amount to ^300, 000. For the year 1888, 

 the actual sales of our celery were nearly $800,000, 

 and it is easy to see that barring the frosts the crop 

 of 1889 would have passed the million- dollar mark 

 — a remarkable showing. 



WiVI. H. WOODHAMS, 3d. 



THE TOMATO WORM PARASITE. 



I am frequently asked concerning the origin of the 

 peculiar egg-like objects often seen on the backs of 

 tomato-worms, and shown in the accompanying illustra- 

 tion. These are not eggs, however, but are the cocoons 

 of a little parasitic fly which is an enemy of the worm, 

 and the way in which they originate is as follows : Some 

 fine summer day, when the tomato-worm is enjoying his 

 meal of the leaves or fruit of the tomato, a small, black 

 four-winged fly alights upon his back, and deposits be- 

 neath his skin by means of a long needle-like instrument 

 called the ovipositor, great numbers of minute eggs. In 

 a few days these eggs hatch into little legless grubs 

 which absorb the juices of the worm and develop at his 

 expense. In a few weeks the tomato-worm stops feed- 

 ing — its body being literally full of the grubs. When 

 full grown, these grubs bore holes in the back of their 

 host and crawl through the skin and escape. As soon as 

 they are on the outside, they begin spinning white silken 

 cocoons, which are the objects frequently mistaken for 

 eggs. Within these cocoons they change to the pupa 

 state, and in about a fortnight emerge as four-winged 

 flies like those by which the original eggs were laid. 



Tomato-worms, aflected by these parasites, seldom 

 live to change to the pupa state, and never, so far as 

 known, complete their transformations. 



But these little parasites do not always have things 

 entirely to their liking, for they are themselves subject 

 to the attacks of a still smaller parasite which destroys 



primary ones — differing both in form and color. Th s 

 them as they destroyed their hosts. These secondary 

 parasites, as they are called, are quite different from the 



TOMATO-WORM WITH COCOONS OF PARASITES. 



species of primary parasite which attacks the tomato- 

 worm is called by entomologists Apaiiteles congrcgatus . 

 It is black, while the secondary species may be either 

 yellowish-brown or brilliant bluish green. 



An\-one can get these parasitic flies by enclosing some 

 of the cocoons in a box or other receptacle. 



Clarence M. Weed. 



