108 BULLETIN 903, U. S. DEPARTMENT OF AGRICULTURE. 
festation was caused by two wanderers from an adjoining cage. It 
was judged that this infestation must have occurred about June 20, 
when many eggs were hatching in the adjoining cages and many 
rootlets decaying, thus compelling the newly hatched larvae to seek 
food elsewhere. 
INOCULATIONS WITH WANDEEEES. 
On July 31. 1913. 30 wandering larva? were taken from jars in 
the cellar and placed on pieces of sound severed roots in a petri dish. 
On August 13, 25 half -grown phylloxera? found roaming around in 
jars were added. All the latter deserted the roots and died, but of 
the former, three matured August 25 to September 18. A later in- 
oculation (Sept. 25) with 40 young wanderers resulted in none of 
these remaining. Another similar experiment was tried on Septem- 
ber 29, with 10 young wanderers, but it also failed. Thus out of 
135 individual wanderers only three matured. 
In 1914 this experiment was repeated, and two pieces of sound 
severed roots were inoculated in a petri dish, one with 8. the 
other with 40 wanderers. In this case a layer of moist sand was 
placed below the roots, whereas in 1913, only filter paper had been 
used. Of the smaller lot 1 and of the larger lot 20 matured. Thus 
On August 28, 15 wanderers from jars in the cellar were placed on 
the living root of a Tokay, and 3 of these hibernated and developed 
the following spring. 
In the autumn of 1913 an attempt was made to inoculate the roots 
of sound potted vines by means of wandering larva? placed upon 
the surface of the soil in the pots. For this purpose, 35 wanderers 
were placed on the soil of each of four potted vines (Resistant 
hybrid. Sept. 18 ; Agawam, Sept. 23 ; Burger, Sept. 26 ; Thompson's 
Seedless, Oct. 6). In no case did the wanderers succeed in inoculat- 
ing the roots. The soil, however, contained extremely few cracks. 
The following year this phase was pursued further. Sound pieces 
of roots were planted 4 inches below the surface in four 9-inch pots. 
On July 8, 30 wanderers were placed on the soil surface of the first 
pot, the soil being cracked from having been watered the previous 
day. The root below was never infested. The soil of the second 
pot was watered to cause it to crack extensively. After it became 
well cracked about 25 wanderers were shaken on it. July 8. An ex- 
amination of the root, August 25, showed it to be infested with a 
thriving colony of phylloxera?. In the third pot the soil was not 
watered: consequently there was no cracking. On July 12, 50 wan- 
derers were shaken out on the surface. Xo infestation of the root 
