246 Mottier . — Development of the Spermatozoid in Chara. 
The first indication of the development of the spermatozoid is the 
movement of the nucleus from near the centre to one side of the cell 
and a slight contraction of the entire protoplast. The side towards which 
the nucleus moves is designated by Belajeff as the ‘dorsal/ and that 
directly opposite as the ‘ ventral ’ side of the cell. By the side or lateral 
wall is meant that which is parallel with the longitudinal axis of the 
spermogenous filament. The contraction of the protoplasm is most 
pronounced at the sides, while it is withdrawn very little or not at all 
from the transverse walls. About this plasma-cylinder there now appears 
a ring-shaped groove (loc. cit., p. 33) which, it is stated, is to play an 
important role in the further development of the spermatozoid, since in 
this groove the cilia are to be developed. There now appears a small 
plasmic protuberance at the boundary between the nucleus and the 
cytoplasm, i. e. at the dorsal side of the cell, or that which will become 
the convex side of the developing sperm, from which the cilia arise. 
‘ Den Beginn der Entwickelung des Spermatozoidenkorpers kennzeichnet 
das Auftreten eines kleinen Plasmahockers an der Grenze zwischen Kern 
und Cytoplasma. Dieser Hocker begiebt sich in die ringformige Rinne 
und ist der Seitenwand der Zelle zugewandt. Am deutlichsten ist das 
Hervortreten dieses Hockers von einer der flachen Seiten der spermato- 
genen Zelle aus zu verfolgen (loc. cit., Fig. 1 5 a). Dieser Hocker entspricht 
augenscheinlich den “ glanzenden Piinktchen ” des Mettenius und den von 
Goebel beschriebenen “ Kopfen.” Aus dem Hocker wachsen zwei kurze, 
elastische Faden hervor. die beide parallel der Seitenwand, aber in ent- 
gegengesetzter Richtung verlaufen.’ 
With the further development of the spermatozoid the protuberance 
or nodule (Hocker) undergoes a change in position, whereby it gradually 
moves to the side of the cell opposite the nucleus. From the protuberance 
to the nucleus extends a delicate thread staining intensely red with fuchsin. 
With the further growth of this thread the protuberance is pushed farther 
away from the nucleus (loc. cit., Fig. 16). This thread lies in the cytoplasm, 
from which only the protuberance, bearing the cilia, protrudes into the 
groove. The thread with its cilia-bearing protuberance forms the anterior 
end of the spermatozoid. Simultaneously with the development of the 
anterior end, that of the posterior extremity is to be observed. At the 
side of the nucleus opposite the point of origin of the plasmic protuberance, 
there appears in the cytoplasm a homogeneous thread or band, which 
grows parallel with the side-wall of the cell and in the opposite direction 
to that of the anterior end. This thread is considerably thicker than 
that which bears the cilia. Its free or posterior extremity protrudes out 
of the cytoplasm into the groove, and forms a beak-like outgrowth (loc. cit., 
Figs. 1 6, 17, and 19). The cilia-bearing filament continues its growth 
within the cytoplasm and until it has reached a middle point on the 
