438 WILLIAM M. GOLDSMITH 
1. INTRODUCTION 
The present paper follows the development of the germ cells 
of the male from the early spermatogonial stage to the mature 
spermatozoon, presents, so far as is possible, a study of the germ 
cells of the female, and considers the somatic divisions. The 
points of chief interest and importance are as follows: 
1. The formation of syncytia in the early spermatogonia and 
their relation to the later stages of cellular development. 
2. The marked difference between the early and last sperma- 
togonial mitoses. 
3. The numerical relations between the spermatogonial, oogo- 
nial, somatic, and first and second spermatocyte chromosomes. 
4. The striking contrast between the behavior of the chroma- 
tin material in the growth period of the primary spermatocyte 
and that in the primary oocyte. 
5. The presence and behavior of a double odd-chromosome.? 
6. The great variety of abnormal mitotic figures and their 
relation to the centrosomes and spindle fibers. 
2. REVIEW OF COLEOPTERAN CYTOLOGY 
Although about seventy species of beetles are referred to in 
cytological literature as having been studied, the detailed his- 
tory of the germ cells has been followed in only three or four 
species. Practically every worker seemed to consider his task 
completed when he had demonstrated the presence of an unequal 
pair of heterochromosomes. 
Of the sixty-eight species listed by Harvey (16) forty-five are 
attributed to Miss Stevens. Since she was primarily concerned 
with the sex-chromosomes, her observations on the other parts 
of the cell were only incidental and usually very meager. She 
gives the spermatogonial, oogonial, and first and second sperma- 
tocyte numbers of chromosomes in only seven species. 
4 Since this body behaves as the odd-chromosome in many forms, but in the 
present material is bipartite and may at certain times appear as two distinct 
chromosomes, the term ‘double odd-chromosome’ is used. Throughout this 
paper large ‘X’ is used to indicate the larger element of this bivalent body and 
small ‘x’ the smaller element. 
