488 ARTHUR BOLLES LEE. 
“ forme pelotonnée”’) is common to all Arthropods. The seg- 
mentation of the skein takes place very generally after the 
manner in which it is known to take place in the typical ex- 
amples of animal and vegetal mitoschisis; that is to say, the 
skein breaks up irregularly into segments scattered without 
order throughout the whole extent of the nucleus. But very 
generally also it does not break up into irregularly-shaped and 
scattered segments, but into parallel bars. The skein 
arranges itself in long loops regularly set in zones parallel to 
the axis of the future spindle, arranged, that is, like the ribs 
of a melon (fig. 15). These loops then thicken in the equato- 
rial region, and thin out towards the poles. They thin out at 
the poles till they break there (fig. 16), and we get a system 
of free bows set on parallel zones round the axis of the nucleus. 
The bows become shorter and thicker, and, either retaining 
their longitudinal position or becoming inflected in the middle 
towards the centre of the nucleus, constitute, without further 
change of place, a mother-star (“ couronne équatoriale”) of 
straight or bent segments, as the case may be; that is to say, 
mother-stars like figs. 6 and 18. 
This mode of segmentation occurs, together with that of 
segmentation into scattered fragments, in all classes of 
Arthropods. 
The Mother-Star—‘ Couronne Equatoriale.”—The segments 
resulting from either the one or the other of these processes 
arrange themselves at the equator in a group corresponding to 
the “Sternform” of Flemming. They may form a regular 
circle situated on the periphery of the spindle, or they may 
form a plate occupying the whole section of the spindle. The 
positions they may take relatively to the filaments of the 
spindle are very various. Straight segments are generally 
attached to their filaments by their whole length; the segment 
lies on its filament (figs. 6,18). But they may be attached to 
which is its linguistic homologue. But it appears better to keep “‘clew,” for 
the tight ‘“ Knauel” which I hold with Carnoy is the typical form of the 
resting chromatic element; using “skein” for the very peculiar expanded 
form known as the ‘ convolution.” 
