) Te GOTE TURESSON 
It seems therefore safe to conclude that the series in question is 
made up of hereditary dwarfs, which, at least in the experimental 
fields at Akarp, are perennials, as distinct from the ordinary tall grow- 
ing A. tripolium. Within the dwarf series, moreover, all kinds of 
branching types might be found just as in the ordinary form showing 
that certain characteri- 
stics vary as much in 
the dwarf variety as in 
the ordinary tripolium. 
Modificatory dwarfs 
of A. tripolium, called 
forth by insufficient 
water and food supply, 
might also probably be 
found in nature. As to modificatory perennials of A. tripolium the sta- 
tement is made by BucHEnau (1896) that the plant becomes perennial 
when eaten by animals or cut down. Both modificatory and hereditary 
dwarfs might be contained in the var. diffusus of the floristic 
handbooks. As to the latter group it should be noted that it is 
not the dwarf as seen in the culture which conforms to the var. 
diffusus; it is only the plant that results from a modificatory dwarf- 
ing of this dwarf in the natural habitat which fulfils the pre- 
scription given in the diagnosis. 
Fig. 3. Aster tripolium. Hereditary dwarfs. 
B. SUCCISA PRATENSIS. 
This species is rather common in the upper part of the salt mea- 
dows along the coast of Scania. It is usually dwarfed in these loca- 
lities, and the most extreme form, which only attains a height of 
at most 85 mm., is known under the name f. nana Bolle. Series of 
this extreme dwarf were collected and transplanted from Torekov and 
Hallands Väderö (N. W. Scania) in 1919, and a set of the ordinary 
swamp plant, as found in the inland, was transplanted from Stehag 
(middle part of the province) in 1920. Table 1 lists some of these 
series (series 34 from Torekov, 35 from Hallands Vader6, 118 
from Stehag) and gives the lenght (in mm.) of the longest flowe- 
ring stem of each plant when transplanted and as found in 1921 
and 1922. 
Fig. 4 illustrates the habitus of the dwarfs used in the series 34 
and 35. They have all increased in length under culture, as may be 
