1914] ELKINS—MATURATION IN SMILAX 37 
somes in the spireme. The chromosomes in Smilax herbacea never 
appear as definite units until the segmentation of the spireme. 
PostsyNApsis.—The much coiled filament of late synapsis 
emerges as a fairly thick thread slightly beaded (fig. 8), which later 
assumes a homogeneous character. The double nature of the 
spireme is early discernible (fig. 9). With the continued loosening 
of the knot the split is sometimes obliterated, but the spireme as 
it is distributed throughout the nuclear cavity is distinctly double; 
this separation of previously paired* chromatic elements does not 
appear simultaneously in all parts of the spireme (figs. 10, 11, 12). 
Shortening and thickening of the spireme proceeds as usual, fol- 
lowed by a sort of semi-segmentation of the double filament. At 
intervals along the spireme occur places where each longitudinal 
half is apparently constricted to a delicate thread (fig. 13). This 
appearance is due doubtless to incomplete transverse segmentation 
with subsequent pulling apart of the double segments; the attached 
portions thus are drawn out into fine threads. The bivalent chro- 
mosomes resulting from the completion of the transverse division 
of the spireme are long and slightly twisted about each other 
(figs. 14, 14a). Though not a typical strepsinema, this condition 
corresponds to strepsinema as described by GREGOIRE (17). 
The shortening and thickening process continues, resulting 
in the characteristic diakinetic gemini, the univalent halves of 
which lie, indiscriminately (fig. 15), parallel, at right angles to each 
other, or in the form of V’s or X’s. Traces of linin threads can be 
seen attached to the ends of the chromosomes. The nucleolus 
is present at this stage (though not figured), but disappears before 
the metaphase. Small globular bodies scattered about among the 
gemini appear in many of the nuclei in addition to the nucleolus. 
These are probably small nucleolar bodies as previously described. 
MeETAPHASE.—Many of the gemini retain the semblance of a 
V on the spindle (fig. 16), though occasionally the homologous 
chromosomes are oriented in a straight line. Intermediate stages 
occur between these two types of orientation. In many cases the 
chromosomes show a distinct splitting while at the equator; this 
is more marked as the chromosomes pass toward the poles, though 
t Previous pairing is assumed to have taken place. 
