THE CABBAGE BUTTERFLY 57 



jection, or handle, by which the scales are attached to 

 the wing membrane. Examine the wing where the scales 

 were removed, and note the manner in which the scales 

 were laid on the wing. With a brush, carefully remove all 

 the scales from the wing, both above and below. Better 

 still, dip the wings in alcohol, then immerse them for a 

 minute in dilute hydrochloric acid (one part acid to nine 

 parts water), and then place them in Labaraque solution 

 (hypochlorite of sodium), until clear and transparent. 

 Finally place them in alcohol again until they rise and float. 

 Then mount them in alcohol for immediate study. 



(If it is desired to make a permanent mount one should proceed 

 as follows : Transfer the wing from the alcohol to a clearing mixture 

 (two parts by weight of carbolic acid crystals and three parts of 

 rectified oil of turpentine) and allow it to remain there ten minutes. 

 Finally transfer it, together with some of the clearing mixture, to 

 a glass slip, put some Canada balsam on top, and cover with a cover* 



Note that the wing is transparent. Observe the veins 

 running lengthwise of the wing. Note the few cross 

 veins. 



Make a drawing of the right front and hind wings show- 

 ing all the veins in each. 



How many legs has the butterfly? Note that each one 

 is divided into segments. Make out. each segment, coxa, 

 trochanter, femur, tibia, and tarsi. 



Make a drawing of the leg. 



Observe the difference in shape of the thorax from that 

 of the locust. 



Make a drawing of a side view of the abdomen. 



B. THE LIFE HISTORY OF THE CABBAGE BUTTERFLY. 

 The life history may be followed on cabbage plants in the 



