428 EDWARD E. WILDMAN 
we see the actual penetration of the nuclear membrane by this 
material.4 Once in the cytoplasm it takes spherical shape as 
tiny granules, or as droplets easily visible under the low power 
lens, according as the quantity of material transuding at that 
point is larger or ‘smaller. These droplets have long been known 
as the ‘refringent granules.’ Their refringent appearance, how- 
ever, is acquired after they have reached the cytoplasm. It is 
due to the formation of yolk within them, as will be shown later. 
The material of which they consist is therefore a yolk-forming 
substance. . 
Such cytoplasmic inclusions in gland and sex cells, con- 
trolling secretion there and staining blue after Benda’s stain, 
are called by many cytologists ‘mitochondria.’ But these are 
thought to be wholly cytoplasmic in origin, having nothing to 
do with the nucleus or its contents. We cannot therefore use 
this term to represent these yolk-forming granules in Ascaris 
spermatocytes, for they arise in the basichromatin or karyo- 
chromatin of the nucleus and pass out into the cytoplasm. 
‘Meves uses the term ‘plastochondria’ to represent cytoplasmic 
granules arising in the oxychromatin or plastochromatin, and so 
indicates their origin and nature. I would suggest the term 
‘karyochondria’ for these yolk-forming granules, because it like- 
wise indicates their origin and nature.’ The observation of the 
migration of the karyochondria from the nuéleus leads to an 
4 JT am indebted to Professor McClung for confirming this observation. 
°> The following table will define the terms ‘karyochondria’ and ‘plastochon- 
dria’ as they are used in this paper: 
»Karyochondria 
Origin Function Equivalents 
(Arise in the basi- Yolk-forminggran- Cytoplasmic nu- 
chromatin: i.e., ules, which very cleoles 
chromatin net- 
work, chromatin 
nucleolus or kar- 
{  yosome, and 
chromosomes 
soon become 
yolk vesicles. 
These fuse to 
form the ‘refrac- 
tive body’ of the 
spermatozoon 
Pseudochromo- 
somes 
Accessory nuclei 
Vitelline body 
Trophochromatin 
Ergastoplasm of 
Prennant and 
Bouin 
Mitochondria of 
Meves and Korff 
