AN EXTRA DYAD AND EXTRA TETRAD IN CAMNULA 409 
Lutz (712, ’16, 717), and Hance (18a, ’718b). But no authentic 
instances of inconsistencies in the chromosome count within the 
germ tract of an individual, previous to the reduction divisions, 
seem to be recorded. 
Holt (17) has described multiple complexes in the degenerat- 
ing gut cells during the pupal stage of Culex pipiens. Hance (717 
and ’18 a) reported fragmentation of the somatic chromosomes in 
the pig and Oenothera scintillans, but states that the number of 
chromosomes in the germ cells is constant for each individual 
and species, and later observations by this author (18 b), on 
better material, indicate that he might have been mistaken in 
regard to the somatic complexes of scintillans. 
A well-known ease of variations in the chromosome count of 
the individual is that of Ascaris megalocephala (Boveri, ’99 and 
04; Bonnevie, ’01). In Ascaris the somatic chromosomes un- 
dergo segmentation; but here, as in the three species referred to 
in the preceding paragraph, no numerical variation is reported 
for the germ cells. 
In this paper we are concerned only with variations in the 
germinal complex appearing within the individual. For this 
reason the foregoing and other apparent or real inconsistencies 
in the somatic chromosome count will not be discussed (Della 
Valle, 709; McClung, 717; Parmenter, ’19). 
Most workers on orthopteran material are familiar with the 
giant-cells (Hartman, 713) which sometimes occur among the 
spermatogonia and spermatocytes in the Acrididae. These con- 
tain usually double the number of chromosomes. Frequently 
they are clearly seen to be pathological and degenerating. It is 
evident that, although they may complete the process of trans- 
formation, they never produce fully functional spermatozoa, for, 
among the more than forty genera (McClung, 714, ’17) of this 
family which have been studied, no grasshopper with more than 
two extra chromosomes has hitherto been reported. 
Foot and Strobell (12) state: ‘‘In Euschistus variolarius the 
number of independent chromosome fragments is most variable, a 
fact easily and definitely determined by the aid of the large 
number of photographs we have taken of complete groups of 
chromosomes in a single embryo. 
