WINE-MAKING IN CALIFORNIA. 65 



regarding moulting, and change of form, when they revive 

 later in the spring. 



In previous cases, where no soil was used and the tempera- 

 ture of the laboratory influenced them, eggs have been pro- 

 duced in mid-winter, and production continued until the root 

 had decayed. 



The soil of the above sample was moistened in December, 

 and a good supply of grass roots and shoots started, but have 

 since dried up. 



It has never before been shown that the winter habits in 

 California differed in the least from eastern countries. The 

 winter of 1884-85 has shown that California climate is spe- 

 ially favorable to the life of the phylloxera. A period of 

 three months will almost include the total time of inactivity, 

 for we find active insects on the last of November, and newly- 

 laid eggs on the first of March. . 



Moulting of Hibernants.\t is usually supposed that a 

 certain number of moultings is necessary before the hiber- 

 nants assume the mother state. This, I think, is only par- 

 tially true here, and applies, if at all, to the youngest insects 

 which pass as hibernants, and which were not fully developed 

 when winter came on. 



Numerous specimens have been carefully watched during 

 the proper period, and no movement whatever was noticed 

 until the insect began laying eggs. It was further observed 

 that the abundance of young larvae found at the close of the 

 season in November were in about the same position, and ap- 

 parently not changed in the spring when egg-laying began. 



Sterile Winged Form. The table speaks of two different 

 appearances of the pupa and winged form. Undoubtedly 

 this means the fertile and sterile kinds; the former alone has 

 been produced during our experiments, although it was 

 through the latter that the winged form was first found in 

 California. These were observed in 1879, by Dr. Hyde of 



