34 
UNIVERSITY OF CALIFORNIA—EXPERIMENT STATION 
of mouth when grasshopper is eating. Carefully dissect the mouth, 
showing all the parts. Names of the parts. (See Comstock’s Hand- 
look of Nature Study for Teachers —an invaluable help.) Look on 
the head of the grasshopper for its eyes. How many? Describe the 
feelers or antennae. They are the organs of touch. Raise the wings 
and find the ears of the grasshopper. How many? How does the 
grasshopper make its music? Various kinds of grasshoppers. 
Describe the devastating grasshopper; color, spots on hind legs, wings, 
etc. Life history. How different from life history of the cabbage 
butterfly? Food plants of this grosshopper. Method of control. 
Mosquitoes .— (See Bulletin No. 178, “Mosquito Control,” College 
of Agriculture, Berkeley.) What do children know already about the 
mosquito and its habits? When are mosquitoes most active? When 
and where do they rest ? What do they eat ? Most live largely upon 
juices of plants as they do not have a chance to suck the blood of 
animals. Only the females bite. Discuss life history. Breeding 
places; eggs, larvae or wiggle tails? How long does it take for the 
eggs to hatch? Position of larvae in water. Larvae of malarial 
mosquitoes almost parallel with surface of the water. Larvae of 
common mosquito beneath surface of water at an angle of about 
forty-five degrees. How does the larvae breathe? Change of larvae 
to pupae. Description. Do the pupae move as did the larvae ? How 
does the pupae breathe? Does it eat anything? Watch for the pupae 
skins from which have emerged the adult mosquito. _ Methods of 
control. See also Farmer’s Bulletins No. 155, IT. S. Dept, of Agri¬ 
culture, on “How Insects Affect the Health in Rural Districts.” 
4. Physical Phenomena and the Inorganic World 
Heat .—Chief source, Nature. How heat produces light. Differ¬ 
ence between heat and light. Discussion of primitive fire-making. 
Modern way. Various ways of producing heat—friction, combus¬ 
tion, etc. Ways in which heat may be transmitted. Explanation ot 
conductor and non-conductor. Application to kinds of clothing, 
weight, material, color, etc. Meaning of fireproof buildings. First 
aid for a severe burn. Meaning of “spontaneous combustion.” 
Illustrations of action of heat in common affairs of life, as pouring hot 
water into a glass dish. 
Crystals .—Illustrations in nature. Examine ice and snow; surface 
of freshly broken rocks or minerals. How make crystals with common 
salt or with alum ? Blue vitrol is a poison yet it makes fine crystals. 
What is rock candy? What precious stones are crystals? 
