302 Wisconsin Academy of Sciences, Arts, and Letters. 
describes in Spinacia the compact structure of the chromosomes 
as being changed into a reticular one by means of numerous small 
vacuoles, which slowly increase in size, thereby distending the 
surrounding material, so that each chromosome is transformed 
into the nuclear reticulum, which is a complex (< reseau de reseaux” 
as described by Gregoire. Nemec (’99) describes a peripheral 
and internal vacuolation of the telophasic chromosomes of Allium 
and the presence of an axial row of vacuoles and small alveoli 
within the chromosomes, the chromatic substance becoming re¬ 
solved into numerous fine granules, which spread out along the 
anastomoses of the linin reticulum. In a later work Nemec (’10) 
supports Gregoire’s view of the telophasic transformation, ob¬ 
serving in many telophasic chromosomes the same vacuolated ap¬ 
pearance, often showing a distinct axial row, or one large vacuole 
running throughout the length of the chromosomes. Nemec notes 
certain nodal points during the distribution of the chromosomes, 
located at their periphery, and states that if we are to accept Bon- 
nevie’s (’08) idea of spiral differentiation we must admit the 
presence of several peripheral spiral bands. Nemec maintains 
that these nodes or knots are not independent elements, but that 
they are located where several lamellae or threads of chromatic 
substance meet. Not only may the densely colored portions of 
the differentiating and distributing chromosomes appear as spi¬ 
rals, but Nemec thinks they may show as rings, rods, etc., which 
may account also for Miss Merriman’s (’04) conception of te¬ 
trads. 
Miss Digby (’10) in contrast to Gregoire’s observations, finds 
no “such diagrammatic vacuolation of all the chromosomes” in 
Galtonia, but observes that vacuolation may be seen in certain 
regions and not in others. By transverse segmentation the chro¬ 
mosomes first break up into certain definite portions of various 
sizes, which remain connected as they become distributed into a 
more or less beaded reticulum. In her later work on Crepis and 
Osmunda, Miss Digby (’14, ’19) supports in principle the view 
stated above. 
The phenomena of the telophasic transformation as described 
by Muller (’12) for Najas agree essentially with the descriptions 
of Gregoire. 
Lawson (’03, ’ll, ’12) first studied the vacuolation of chromo¬ 
somes in Passiflora and Equisetum, but describes a like condition 
for those of certain other plants; this process he thinks is a 
