CHANGES IN REPRODUCTIVE CELLS OF ELASMOBRANCHS. 307 
Viewed from above, such chromosomes present the appearance 
represented in Diagram IV, 1, c, and when the chromosome 
divides, the polar extremities lengthen out, while a transverse 
split appears across the equatorial thickening, and the daughter 
V’s, gradually separating, present a curious fourfold appear- 
ance represented in d, e. 
Diagram IV, representing division of heterotype chromosomes. (1) In 
Hlasmobranchs. (2) In Phanerogams (according to Guignard and 
Strasburger). (3) In Phanerogams (after Farmer). a, 0, ¢, d, e, 
corresponding stages in division. 
56. In phanerogams the division which succeeds the long rest 
after the formation of the spore mother-cells, and which in 
general superficial characters corresponds to the synaptic 
phase (cf. § 19) among animals, differs, like its zoological 
counterpart, entirely in the arrangement of the chromatin 
from all the previous mitoses of the reproductive cycle: But 
the manner in which the daughter-chromosomes separate and 
go apart is, according to Strasburger and Guignard, quite 
different from what obtains in the corresponding animal cells. 
. According to these authors, the chromosomes, after arising as 
stout, longitudinally-split rods (Diagram LV, 2, 0) are attached 
