240 NATURK vSTUDY. 



be as many as nineteen piles, or even more, and perhaps 

 they are right. But the older they grow and the wiser 

 they get to be the less willing they are to agree among 

 themselves about the number of piles that ought to be made, 

 and so, as we are neither very old nor very wise, and as 

 seven is a handy number, we will make seven piles of all 

 the kinds of insects that we catch, and in our next lesson 

 we will try to find some things that will be true of all the 

 insects in one pile, and will not be true of the insects in 

 any other pile. 



Through a printer's blunder, the beautiful story of Zek- 

 ko and his family, entitled " Two Ears, " was reprinted in 

 Nature Study without credit. No complaint has been 

 received, but common fairness demands that we make such 

 amends as possible b}' stating what was intended to be 

 stated in the first place, that "Two Ears," written by 

 Alva Deane, first appeared in the Kindej'-garteyi Revietv for 

 February, 1892. 



An interesting demonstration of the intelligence of the ant was 

 made by a student in the biological department of the University 

 of Pennsylvania. The young man constructed a roadway two feet 

 in length of metal and divided it into two parallel paths, separated 

 by high partitions. One of the paths he painted red and the other 

 blue, and at their end, in plain view, he put a morsel of rich cake. 

 Then he set an ant at the beginning of the roadway. The ant at 

 once made for the cake over the red path, whereupon the student 

 turned on a lamp under his mechanism and heated the path to an 

 uncomfortable degree. The ant kept on and finally secured the 

 cake, but on its return it must have told itself that it had had a 

 mighty uncomfortable journey. Several hours later the student 

 brought it out again, another morsel of cake being set at the end of 

 the roadway. The ant thought a moment and then started for the 

 cake over the blue path. It remembered that the red one had been 

 hot. To prove still more conclusively that it remembered, the stu- 

 dent next blocked up the blue path, whereupon the ant did with- 

 out the cake rather than venture after it by the red one. — Philadel- 

 phia Record. 



