Kinsey: Gall Wasp Genus Cynips 
157 
altho we cannot raise the same question for Schenck’s records, 
it seems not to have been verified by later experience. 
According to Beyerinck (1883: 25) the abdomen of one of 
the larger agamic females may contain as many as 178 large 
eggs, altho a smaller individual may have only a score of 
eggs. Hartig (1840) first figured the structure of the ab- 
domen of divisa, showing details of the ovipositor, eggs, and 
ovaries which we have copied in the present paper. Rossig 
(1904) used larvae of this species in his study of the origin 
of the gall-producing stimulus of gall wasps, and his paper 
gives many details of the larval structure of divisa, especially 
of its oenocytes and Malpighian tubules. 
In the early search for the missing male of the gall wasps, 
Hartig gathered 28,000 galls of this species and bred between 
9,000 and 10,000 adult insects which were, of course, all 
females. This observation attracted considerable attention 
at that time, and provided some impetus to the investigations 
which resulted in our present knowledge of alternation of 
generations among these insects. Hartig first recorded his 
observations as applying to the ordinarily rare wasp, Cynips 
disticha; but in 1843 (Germar Ent. Zeit. 4:398) he stated 
that the observations applied to Cynips agama. Mayr-Fitch 
(1876, The Ent. 9:149) noted the correction, and later 
authors have accepted it. 
Adler, in 1877, observed that the agamic divisa oviposits in 
unopened, terminal buds of the oak. Altho he obtained none 
of the galls of the alternate generation in these first experi- 
ments, his results in 1878 were more fortunate. The adults 
lived over a period of fourteen days during which a series of 
buds were pricked by the insects, and from these he obtained, 
on the young leaves in the following spring, five galls of 
verrucosa, the bisexual form described below. 
The histology of the gall of divisa has been described by 
Lacaze-Duthiers (1853), Fockeu (1889), Hieronymus (1890), 
Kustenmacher (1894 acc. Kieffer 1901), and in more detail 
by Weidel (1911). These studies have all emphasized the 
similarity of divisa galls to those of Cynips folii, noting only 
such differences in epidermal coloring materials, more openly 
spongy parenchyma, hardness, size, and shape as are apparent 
in examining the gall with one’s naked eye. Kiister (1911) 
records only 53.5 per cent of water in these galls, which is 
