} 
1897] CURRENT LITERATURE 303 
thread, staining intensely with fuchsin, runs along the upper edge of this 
plasma band, which is the spiral thread or band formed by the extension of 
the sphere. The cilia, somewhat over forty in number, are attached to the 
two front turns of the spiral body of the spermatozoid, which in the mature 
condition does not have more than three turns. 
In the spermatic cells of the Equisetinez the bodies associated with the 
nucleus are not round as in the ferns, but crescent shaped, with the convex 
side turned toward the nucleus. Here, as in the ferns, the first change 
observed in the metamorphosis of the spermatic cell is in this body, which 
changes its form, turning its concave side toward the nucleus, around which 
it then begins to extend. It soon assumes a thread-like form and encircles 
the nucleus in the form of a spiral. Here also, as in the ferns, the writer was 
able to discover that an intensely colored thread runs along the edge of a less 
intensely stained band. The gradually elongating thread, which appears at 
mature antherozoid. While the spiral thread and band are developing, the 
nucleus gradually elongates, as in the ferns, and finally assumes the form of 
a short spiral 
The mature spermatozoid has the form of a spiral with about two turns, 
and bears a large number of cilia on the front turn. The anterior portion of 
the spermatozoid appears as a comparatively small band, while the posterior 
portion forms a much thicker body and contains the nucleus which, as in the 
ferns, is surrounded by a sheath of cytoplasm. The thread which is formed 
from the crescent shaped body of the spermatic cell runs along the upper edge 
of the front end of the spiral. 
In the Equisetinee Belajeff was able to trace plainly the development of 
the cilia from the spiral thread formed by the extension of the crescentshaped 
body. In the ferns this connection was not traced, but from the analogy of 
the two cases, the author thinks there can be no doubt but that the spherical 
body (Nebenkern) in the ferns performs the same function. 
By comparing these results with his previous studies of the spermatogene- 
sis in Characez, the writer thinks that the tubercle (Hécker), which he found 
_ there in the spermatic cells, corresponds to the cilia forming body in the 
Equisetinee. The tubercle, which has also been observed by Strasburger, lies 
near the nucleus, and becomes extended into a thread that ultimately bears 
the two cilia. 
In a third preliminary paper Belajeff discusses the similarity of the phe- 
homena of spermatogenesis in animals and plants.* The changes in the form 
% Ueber die Achnitehteatt r. in der Spermatogenese bei Thieren 
So 
Pflanzen. Ber. d. deutsch. bot Ges. 15 : 342-345. 1897. 
