SPERMIOGENESIS OF HELIX ARBUSTORUM. 
333 
to be transferred from one cell generation to the other. This body has 
not been mentioned by the other authors working upon the spermio¬ 
genesis of Helix, neither has the present author found it in the resting 
spermatocytes of H. arbustorum,. Bolles Lee, however, regards as 
hyaloplast not only the clear body found in the nucleus o a f the sper¬ 
matids, but also the clear one which takes up a position at the outer 
side of the nuclear wall turned toward the axial filament, in the centre 
of which lies the centriole. This latter body is identical, as mentioned 
above, with the centrosphere. Neither may the other part of Bolles Lee’s 
hyaloplast be regarded as a distinct constituent part of the cell. I am 
of the opinion that this part of the supposed hyaloplast is identical 
with the nuclear sap pressed out from the nucleus. I regard as a proof 
of this suggestion, the fact of its appearing only when the chromatin 
begins to contract, and when the nucleus begins to decrease. It grows 
for a time proportionally to the contraction of the chromatin, but 
afterwards gets out of the nucleus, later separates from it completely, 
and its substance dissolves itself in the cytoplasm, therefore it does 
not play any part in the building up of the spermatozoon. 
In the next stage of the development the spermatid begins to 
lengthen in the direction of the axial filament (PL XL, Pigs. 7., 8.). 
At the same time a small dark corpuscle appears at the opposite pole 
of the nucleus close to the nuclear membrane raised by the pressed 
out nuclear sap (Pl. XI., Fig. 7.). This corpuscle retains its relative 
position to the nucleus even when the liquor vacuole disappears, and 
when it transforms itself into a rodlike feebly stainable body (Figs. 
8., 10.). From this corpuscle develops the perforatorium. Its origin is 
unclear. I have not had the opportunity of finding it in an earlier 
stage than is shown on Fig. 7. From the fact that it then lies within 
the nucleus can be concluded that it takes its origin from it. Nus¬ 
baum (87), Godlewski (80, 31) and Prowazek (98) have stated it to 
be identical with the nucleolus, but this opinion must be incorrect, 
because the nucleus of the spermatid never has a nucleolus. 
On Figs. 9. and 10., PL XL, considerably prolonged spermatids 
are to be seen. Their nucleus takes a position in one end of the cell; 
it is heartshaped; its summit is occupied by the dark corpuscle from 
which the perforatorium develops ; in the hollow on the opposite pole 
lies the centrosome. The proximale centriole is prolonged into the in¬ 
terior of the nucleus (PL XL, Figs. 10., 16.). The nebenkern is well 
developed and lies near the nucleus. In the cytoplasm mitochondria 
granules are to be found abundantly; the chromatoid body is still 
present (Fig. 9.). The distale centriole has divided itself into two parts, 
