BoT.-VoL. II.] BYXBEE—LAVATERA. *]1 



Larix, where there is less granular matter, long fibers 

 extend out from the central network — which results, as in 

 Passijlora, from the union of cytoplasmic and hnin threads — 

 to form by their contraction the cones of the multipolar 

 spindle. 



In Cobcea and Lavatera the spindle formation goes on 

 within the dense granular zone. In Cobcea a network is 

 formed as in Larix and Passijlora. In Lavatera the fibers 

 seem to be always distinct and bunch themselves together 

 into a dense mass. The multipolar spindle is formed by a 

 pulling out of the network (Cobcea), or mass of fibers (Lav- 

 atera)., as in the other cases. 



The method of formation of the bipolar from the multi- 

 polar spindle does not seem to vary in the various cases. 



One of the principal differences, then, in the method of 

 the formation of the spindle in the various plants studied, 

 seems to be the time at which the free fibers are formed 

 from the reticulum of the resting cell. In some cases this 

 occurs very early, as in Eqiiisetum and Lavatera, which, 

 however, differ widely in other respects. In other cases, 

 as Larix, the spindle itself seems to be a network much 

 stretched out. 



The granular zone, which is so conspicuous in Cobcea and 

 Lavatera, has been figured in most of the papers on the 

 division of the generative cells of the higher plants. Oster- 

 hout (1897) figures it in the bipolar stage in Equisetmn and 

 Mottier (1897 «) in Podophyllum and Helleborus. Mottier 

 (1897 b^ also speaks of its presence at several stages in 

 the divisions in the embryo-sacs of the Liliacece, but does 

 not seem to regard it as constant in or characteristic of these 

 divisions. Juel (1897) figures it as a prominent ring in 

 Hemerocallis, but does not discuss it at any length. In 

 Passijlora, also, it forms a well marked zone. 



While it is so commonly, perhaps invariably, present in 

 the reproductive cells at the time of their division, it has not 

 been observed in any of the dividing vegetative cells that 

 have been studied. This fact seems to indicate a connection 

 with the two rapid divisions of the reproductive cells for 



