CYTOPLASMIC INCLUSIONS OF THE GERM-CELLS 271 
(1) In the Primary Spermatocyte the idiosome is differen- 
tiated into an outer blue-staining ‘ idioectosome’ and an 
inner purple-staining ‘ idioendosome *. (2) During the prepara- 
tion for the First Maturation Division the idioectosome 
disappears and, during the division, the substance of the 
idioendosome becomes scattered through the cytoplasm in 
the form of minute granules called ‘idiogranulomes’. (3) In 
the Secondary Spermatocyte a new idioectosome is re-formed, 
containing the idiogranulomes. (4) During the Second Matura- 
tion Division the idiogranulomes are again scattered through 
the cytoplasm. (5) In the re-formed idioectosome of the 
spermatid each idiogranulome is seen to be surrounded by 
a clear vacuole—the ‘idiogranulotheca ’. (6) The idiogranu- 
lomes rapidly fuse to form a single large red-staining ‘ idio- 
spherosome ’ enclosed in a large vacuole, the ‘ idiosphaero- 
theea ’ formed by the fusion of the idiogranulothecae. (7) The 
idioectosome now begins to move away to one side and is 
re-named the ‘idiophthartosome’. Meanwhile the idio- 
sphaerosome secretes a crescentic blue-staining ‘ idiocalypto- 
some ’, and is itself known henceforth as the ‘ idiocryptosome ’. 
(8) In the ripe spermatozoon the idiophthartosome disappears 
with the cytoplasm which is lost during metamorphosis. The 
idiocrypto- and idiocalypto-somes together form a double cap 
to the sperm-head called the ‘spermiocalyptra’, and the 
idiosphaerotheea ‘ persists through all later stages and develops 
into a membranous cover for the cap and head of the sperm’, 
and is then known as the ‘ spermiocalyptrotheca ’. 
As we shall mention below, we have not been able to confirm 
the statement of these observers as to the scattering of the 
‘idiogranulomes ’ during the maturation divisions, but we have 
adopted their account for several reasons. 
We cannot, however, feel that Papanicolaou and Stockard 
have really improved the nomenclature of the subject by the 
introduction of these cumbersome new terms. 
In the following table we have placed side by side the new 
terms of these authors and the corresponding synonyms used 
by previous workers. In the third column we have put forward 
