was produced from larvae which the young son of Mr. Fred Burns found on the 

 white sage (Artemisia ludoviciana) . Do not despise the commonest caterpillars. 

 Species may abound one year and be scarce for a number of years. In the early 

 'seventies my father was offered one dollar apiece for Vanessa californica and 

 could not obtain a single specimen. There have been four different years since 

 then when untold thousands of this species could have been gathered at Truckee, 

 when their larvae almost could be termed a pest, and the chrysalids could have 

 been collected by the peck. But if a given species is always plentiful in your 

 locality it pays to raise a few hundreds. You can easily store away a thousand 

 specimens, papered or pinned, and you can dispose of them at some price. You 

 sometimes find sports, freaks or aberrations, which are varieties which differ in 

 coloration from the typical form, and these bring fancy prices. Larvae which are 

 gregarious are reared with slight effort and need not be taken from the bushes 

 until near pupation. 



GEOMETRID LARVAE. 



Never fail to gather Geometrid larvae. You will probably exclaim, if you 

 are a beginner, that you don't know what they are, but you do. They are 

 slender and naked, usually with only two pairs of legs, though rarely they may 

 have three or four pairs. Lacking the number of legs which most caterpillars 

 enjoy, they travel by a grotesque method of looping up their bodies. They are 

 usually called measuring worms, or inch worms. "Geometer" originally means 

 "land-measurer." Many scientists desire to purchase Geometridae. Dr. J. H. 

 McDunnough, 152 Prairie St., Decatur, 111., writes: "I should advise your 

 trying to raise from egg and larva as many of the Geometers as possible. As they 

 are delicate, it is almost impossible to get good specimens on the wing." Louis 

 W. Swett, 501 Washington St., Boston, Mass., says: "Geometrid larvae are 

 very easy to rear, except such as hibernate, which are very few in number." 

 When you capture Geometrid females, by all means try to secure eggs. The 

 greater number are good egg-layers. 



DISEASES OF LARVAE. 



Sick or dead larvae should be promptly removed, and unless of rare varieties, 

 should be destroyed. If a contagious disease appears destroy every infected 

 caterpillar. Cleanse the box with carbolic acid diluted with water, or place it for 

 a day in a tight chest containing formalin. So little is known of the diseases of 

 larvae that remedies are out of the question. If a species is especially valuable 

 isolate the sick larva and vary its surroundings. Perhaps the air in the cage is 

 too dry, or too moist, or insufficient. The sickness may be the result of over- 

 crowding, of unsatisfactory food, of filth or decay, of too little or too much 

 light, or it may be occasioned by parasites. Fungus is a dread foe of caterpillars. 

 Sometimes the odor of carbolic acid or creosote prevents fungus. Be always on 

 your guard against parasites. Save all parasitic insects and send them to insec- 

 taries or to me for study. 



HIBERNATING LARVAE. 



All who have tried to rear hibernating larvae know that a large propor- 

 tion will not live until spring. Perhaps the mortality is great when they hiber- 

 nate naturally. Hulst says: "If kept too dry they die from lack of moisture. If 

 kept too moist they are apt to die from fungus. The efforts should be to keep 

 them at a temperature as steady as possible, and below the freezing point. They 

 should be kept moist, but not wet. The air ordinarily contains sufficient moisture 



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