DAVENPORT: PROCESSES CONCERNED IN ONTOGENY. 193 
this process of localized solid growths the principal differentiations of 
Phanerogams occur. 
IV», 2. An important change of form 
of a protoplasmic mass may occur inde- 
pendently of growth by a rearrangement of 
the nuclei of the mass. 
Good examples of this process are found 
in the development of the larva of Lucer- 
naria (Figure 27); in the development of 
Ctenophores (K. & H., Fig. 67); and in 
the changes of form occurring in the 
» 
“ectodermal basal plate" of Salpa (an 
apparent syneytium), according to the 
figures of Heider ('05, Abh. Sencken- Fig, 27. 
berg. naturf. Ges, Bd. XVIII. Figs. 32, 
40, 41). In so far as this process involves the migration of nuclei, it 
is clearly olosely related to Process I. 1. 
Fic. 28. 
Fig. 27. A, B, C, are three successive ontogenetic stages of Lucernaria. The 
transformation from stage B (36 nuclei in the section) to stage C (383 nuclei in 
the section) is due to a rearrangement of the nuclei, See K. € H., Fig. 49. 
Fig. 28. B, dispersal of elements of the gemmule A, which was formed, as 
illustrated in Figure 5, by the aggregation of similar mesenchymatous elements. 
This process precedes the development of the gemmule into a larva, and accom- 
panies the imbibition of water by the gemmules. After H. V. Wilson, ’94, Jour. 
of Morphol., IX., Plate XVI. 
