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NA Tl 11E-S TUD Y RE VIE I V 



[6:7-Oct., 1910 



list is suggested as some of the adult forms to be recog- 

 nized: 



In the third and fourth year the work of getting acquainted 

 with new forms should be continued. More attention may now 

 well be given to body parts and their use. Life histories should 

 be studied. Especial attention should be given to changes in 

 form and habit. The following three forms are advised for life 

 history work: (i) A land form with incomplete metamorphosis; 

 (2) A land form with complete metamorphosis; (3) A form with 

 aquatic larvae. Make a study of the larva when first hatched 

 or secured and feed it on the material on which it was feeding 

 when secured. If the aquatic form is a dragonfly or damselfly, 

 it will need live minnows or other aquatic forms for food. The 

 dragonfly and damselfly are not so good for life history work as 

 are the may-flies which transform much more quickly. Feed the 

 may-flies upon algae (frog's spit or frog's, spawn as they are 

 commonly called). The breathing of the dragonfly larvae may 

 be shown by putting one in a shallow dish (or saucer) of water 

 and putting the tip of a copying pencil in the water near the pos- 

 terior of the abdomen. The breathing of the grasshopper may 

 be readily observed if one be put under a glass jar for a few 

 minutes. If a dragonfly larvae be put in a dish of water for two 

 or three days without food and then a live minnow or other 

 small aquatic larvae be put in the water, his method of feeding 

 may be readily observed. If a grasshopper be shut up in a cage 

 for a few days without food or drink and then a few fresh blades 

 of grass and a few drops of water be put on the bottom of the 

 cage, he will usually demonstrate his methods of eating and 

 drinking. 



In observing the dragonfly larva it may be noticed that he 

 makes some rapid movements in the water that could not come 

 from swimming with his thin legs. Put him in a dish and barely 

 cover him with water, disturb him with a pencil or pin. If the 



