1893.] MICROSCOPICAL J(^URNAL. 27 



early destruction of the vines and a conse(|uent diiniiuition in the 

 set of tubers. When tlie tubers are attacked tlieir normal j^routh 

 is checked. 



The Potato Moth. — This moth {Lila salanclla) lays its 

 eggs u\\ tlie stem of llie potato, near the btjttom, and at the time 

 when the vines are nearly deatl. The larva.- hatch and enter the 

 ground, where they attack the tubers. They make burrows in 

 the tubers, rendering them unlit for use. Even after housing the 

 potatoes injury continues unless means of prevention are taken. 



A writer in Insect Life advises harrowing the potato stalks 

 up in heaps, and burning them before digging the tubers. The 

 crop should be removed to a safe distance and covered up. 

 The New Zealanders cover their potatoes with live shellfish, 

 thinking tiiat tlie unpleasant odor will keep away the moths. 



The sparnnvs catch these moths in immense numbers, and 

 have been known to practically exterminate them. 'I'his word 

 tor the sparrow, however, tloes not atone for his many anil 

 great sins. 



House Ants of Mexico. — Edward Palmer, an entirely 

 reliable attache of the National Museum, writes from Tepic, 

 Mexico, to Prof C. \'. Riley, the following strange facts: 



Suddenly one afternoon these insects came into the hotel in 

 countless numbers. They assailed the dining-room so that 

 supper had to be taken outdoors. Next morning my room was 

 covered with them ; they swarmed over the roof, the walls, 

 floor, and into every sheet of paper with or without botanical 

 specimens. If I sat down to change dryers, thev swarmed over 

 me to so great an extent that I quit the room. They bit 

 furiously. Their visit was to catch the insects that bore into 

 the wood of the ceilings and make much devastation thereby. 



Perfume of Flowers. — Menard, by a minute microscopic 

 study of the ditVerent parts of flowers, has discovered that the 

 odor-producing oils are located on the inner surface of the corolla. 

 Only a few drops of oil are usually found on the outside. The 

 color pigments and tanin are derived from chlorophyll. The 

 more tliese products are eliminated from it the stronger are the 

 essential oils and the stronger the perfumes. 



BACTERIOLOGY. 



Bacillus Typhi Murium Employed for the Destruction 

 of Mice. — Early in 1892 the tieUl mice had so multiplied in the 

 plains of Thessaly, near the capital town Larissa, that thev had 

 become a most terrible scourge. All means tried for combating 

 them had failed, when the Greek government, upon the advice 

 of Pasteur, inviteil Prof. Loeffler, of Greifswalde, Prussia, to ex- 

 periment with this bacillus, which Loeftler had discovered and 



