LENGTH OF EGG PERIOD. 



The length of the egg-period varies from about three or four days to almost 

 any number of weeks or months. As a good working rule, however, it may be 

 said that eggs will hatch in three or four weeks. Many species hibernate in the 

 egg stages. Never throw away a batch of eggs until you are absolutely sure 

 that they are infertile and worthless. They should be kept in test-tubes, vials, 

 jelly glasses, capsules or in some convenient receptacle where they can be ex- 

 amined daily. By using a magnifying glass it takes but a glance to ascertain 

 ii' a given set of eggs have hatched. This part of the work occupies only little 

 time, but like every other detail of this business must be faithfully and con- 

 scientiously done. When eggs are extremely valuable they should be examined 

 two or three times a day during the period at which the larvae are liable to 

 emerge. Of course, when winter sets in, this part of the work ceases until the 

 first warm days of spring. French says: "The time of the egg period, or the 

 time from deposition to hatching varies in different species, depending somewhat 

 upon the temperature. In some species they hatch in from three to four days, 

 as in Grapta, Colias and Pieris. The Papilios and Danais Archippus hatch in 

 from four to six days; Phyciodes Tharos, in from four to seven days; P. 

 Nycteis, in twelve; Limenitis Disippus, in from five to eight; Argynnis Diana, 

 in fn'teen ; A. Cybele, Aphrodite, Alcestis and Atlantis in from fifteen to 

 twenty, etc." 



TAKING EGGS FROM BAGS AND BOXES. 



If one has the time it is better to line the boxes containing the females with 

 cheese cloth or tissue paper upon which the eggs may be laid, otherwise they 

 will be clued to the inner surface of the box. Some entomologists obtain eggs 

 by placing females in tin or paper mailing tubes, which they first line with some 

 gauzy material. My mother has discovered that when necessary eggs may be 

 removed from any surface by dexterously inserting the nail of the thumb or fore- 

 finger beneath the egg and prying it loose. A little practice renders this safe, 

 but at first you will probably crush a few eggs. It is generally better to chip off 

 thin slices of the surface containing the eggs with the sharp blade of a pen- 

 knife, or cut slips out 01' the card-board with the eggs upon them and place 

 these chips, slices and slips in the receptacle containing the egg. Paper bags 

 are convenient in this respect, for with a pair of scissors you can snip out pieces 

 of the paper with the eggs upon them. Another discovery made by my mother 

 is that if you detach the egg it is sometimes convenient to lay a small patch of 

 damp cheese-cloth upon them. When the cloth is dry the eggs will be found 

 adhering to the patch. A lot of loose eggs gently shaken from side to side 

 will turn bottom side up and when stuck to the cloth will appear in their 

 natural position. 



CARE OF EGGS. 



Eggs require very little care. If in tubes corks should not be inserted 

 tightly lest the eggs mould, but only a little ventilation is necessary. Hibernating 

 eggs in tubes should be corked with a loose piece of cotton to admit a slight cir- 

 culation of air. Do not place eggs in the sun nor let them freeze. All eggs, 

 as well as all larvae and pupae, must be shielded and protected from ants, mice, 

 birds, ichneumon flies and numberless other enemies, which are a constant menace 

 to them in their natural state. All hibernating material should be securely 



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