THE GENOTYPICAL RESPONSE OF THE PLANT 251 
A. patulum var. erectum Huds. of the floristic handbooks includes 
most of the types with an erect habit of growth, while the var. angusti- 
folium J. E..Sm. comprises a great assemblage of prostrate types to- 
gether with dwarfs and hunger forms of the preceding types. 
D. ATRIPLEX SARCOPHYLLUM. 
The A. patulum-like shore Atriplices with thick and fleshy leaves 
are here grouped under this preliminary name. I have shown in a 
former publication (Turesson, 1919 b) that these forms have been 
erroneously grouped with A. patulum, which species they resemble in 
the shape of the leaves. They form together one of the most distinct 
species in the genus, systematically and ecologically, and occur almost 
along the whole Swedish coast, occupying the zone nearest to the water 
(the lower supralittoral belt), where no other species of the genus thri- 
ves well. They flower earlier than any other species of the genus, as 
early as May and June. Sets of seeds and young plants of forms 
belonging to this species have been collected from some thirty different 
localities and cultivated, and a remarkable hereditary variation has 
been found to occur. Furthermore, the geographical distribution of 
the various forms is of great interest. It is found that the eastern 
coast strip is inhabited by a certain group of forms distinctly different 
from the population inhabiting the Sound region, and both these 
groups of forms differ again from the forms found on the western 
coast strip. It is preferable to discuss these different geographical 
groups separately. 
a. The type of the eastern coast strip. 
The forms of this type have the general characteristics of the 
whole group: thick and fleshy, rhombic-lanceolate leaves; long, un- 
branched and, in the upper part, leafless inflorescences; early flowering 
etc. The eastern forms differ from the rest in the branching: they are 
erect, with the basal branches ascending. They have in addition 
somewhat thicker leaves than the forms of the Sound and the western 
coast (see figs. 74e and f). The mean leaf thickness of the east coast 
type has been found to vary between 945 «. and 1155 «., while that of 
the Sound type varies between 893 4. and 1067 “. For purpose of 
comparison it may be mentioned that the thickness of A. patulum has 
been found to vary between 315 u. and 525 u. The values refer all to 
cultivated biotypes. The fruiting bractlets of these eastern forms are 
