1911.] NATURAL SCIENCES OF PHILADELPHIA. 409 



response to other odors, because the time in seconds for each test was 

 exactly the same after as before using the control. 



In view of the above facts we are safe in assuming that the lyriform 

 organs function in some measure as olfactory sense organs. 



(1) The Temperature Sense. — As Gaubert (1892) came to the con- 

 clusion that the lyriform organs are an apparatus to determine tem- 

 perature and perhaps other general senses, a set of experiments was 

 performed in order to test his statement. 



A temperature case was constructed by making a glass case 40 cm. 

 long, 5 cm. wide and 10 cm. high with a cheese cloth bottom. At one 

 end placed at right angles was suspended a tin box 20 cm. long, 10 cm. 

 wide by 3 cm. high, so that only 5 centimeters of one end of this box 

 were under the glass case. At the other extreme end of the tin box 

 was placed a small alcohol lamp to heat the water in this box. A piece 

 of glass served as a cover for the box, the top of which was just one 

 centimeter beneath the bottom of the temperature case. One ther- 

 mometer was laid horizontally on the floor of the temperature case 

 with the bulb over the water. A second thermometer was placed 

 vertically in the other end of the temperature case as a control. Its 

 reading always coincided with that of the normal temperature of the 

 room. Both thermometers had previously been tested. 



Ten specimens of Lycosa lepida, one at a time, were left in the tem- 

 perature case for several hours until they came to perfect rest over the 

 water in the tin box and near the bulb of the thermometer. Now the 

 water was gradually and gently heated. Before varnishing the 

 lyriform organs the spiders moved away from the heated region when 

 the temperature on an average was raised 11.2° C. After varnishing 

 the same specimens moved away when the temperature on an average 

 was raised 12.75° C. Since more specimens of Lycosa lepida could not 

 be found, ten L. scutulata, a very similar form, were used in the same 

 way. Before being varnished they moved away from the heated end 

 when the temperature on an average was raised 15.5° C; after being 

 varnished on an average of 14.2° C. In each test the time was approxi- 

 mately 15 minutes and each specimen was tested with odors after 

 being varnished to see if the varnishing had been well done. Thus 

 before being varnished twenty specimens of Lycosa left the heated 

 end of the temperature case when the temperature was raised 13.3° C. 

 and after being varnished they left that end when the temperature 

 was raised 13.4° C. It hardly seems probable, therefore, that the 

 lyriform organs are an apparatus to determine temperature as Gaubert 

 thought. 

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