WINE-MAKING IN CALIFORNIA. 61 



a. The ordinary egg with which the gall is crowded. 



b. The ordinary larva. 



c. The swollen, parthenogti. ^tic mother, without tubercles. 

 II. The root-inhabiting type, forming knots on the roots, 



and presenting: 



aa. The ordinary egg, differing in nothing from a, except 

 in its slightly larger average size. 



bb. The ordinary larva, also differing in no respect from b. 



d. The parthenogenetic, wingless mother, the analogue of 

 f t but covered with tubercles. 



e. The more oval form, destined to become winged. 

 /, The pupa, presenting two different appearances. 



g. The winged, parthenogenetic female, also presenting two 

 different appearances. 



//. The sexual egg or sac deposited by g, being of two sizes, 

 and giving birth to the true males and females. 



/'. The male. 



j. The true female. 



k. The solitary impregnated egg deposited by/. 



bbb. The larva hatched from k, which, so far as is known, 

 differs not from the ordinary larva, except in its greater pro- 

 lificacy. , 



/. The hibernating larva, which differs only from in being 

 rougher and darker. 



Forms observed in California. In the course of our work 

 we have met all the forms thus far known in the gall-inhabit- 

 ing type; in the root-inhabiting type nearly all of the active 

 forms represented in the table have been observed. They 

 have been developed up to the production of what we have 

 called the true sexual individuals, or, as designated in the 

 table, the true male and female. The winged females which 

 developed upon the roots and were caught in the trap, laid 

 the sexual eggs, but none of them produced the individuals 

 which would naturally have followed. No reason can be 



