May 10, 1912] 
signed, and stating ground for the objection, 
not later than May 1, 1913. 
C. W. Stites. 
Secretary International Commission 
on Zoological Nomenclature 
SPECIAL ARTICLES 
@NOTHERA NANELLA, HEALTHY AND DISEASED 
In my cultures of the evening primrose of 
Lamarck, the pure and self-fertilized seed 
yearly produces a certain percentage of mu- 
tants, among them dwarfs, @nothera nanella, 
the number of which usually amounts to about 
1 per cent. of the whole crop. Of late, these 
dwarfs have been the subject of some discus- 
sion, since Zeylstra discovered the presence of 
a bacterium in their tissues and showed that 
some of their characters, formerly considered 
as specific marks, are, in reality, abnormalities 
caused by this parasite.” From this, some 
authors have erroneously concluded that the 
dwarfs are no real mutants, but only diseased 
individuals of the original type. 
Zeylstra, however, had pointed out that, 
under favorable conditions, the sideshoots of 
the dwarfs may become healthy and lose their 
abnormal characters; but their height re- 
mains the same as in the diseased stems. 
Hence we may assume that, under still more 
favorable conditions, the main stems them- 
selves might grow up healthy, while still re- 
taining the dwarfish stature. 
About half a century ago, Liebig pointed 
out that nitrogenous manure is apt to increase 
the sensitiveness of plants to diseases, whilst 
phosphate of calcium is one of the best means 
to diminish this predisposition. Laurent 
found the same to be true for such diseases as 
are caused by those common bacteria of the 
soil, which, under normal conditions, are 
harmless, but may injure the cultures, when- 
ever the manure is too rich in nitrogenous sub- 
stances. He studied Bacillus fluorescens puti- 
dus and B. coli communis, both of which de- 
stroy the cellwalls by means of their enzymes, 
1H. H. Zeylstra, ‘‘Fzn. Ginothera nanella de 
Vries, eine krankhafte Pflanzenart,’’ Biolog. Cen- 
tralblatt, 1911, Bd. XXXT., pp. 129-139. 
?Sammelreferat by G. Tischler, Zettschr. f. ind. 
Abst., 1911, Bd. V., p. 327. 
SCIENCE 
753 
even before they themselves reach the cells. 
The bacterium of @nothera nanella is of a 
wholly different type, since it is found within 
the living cells and changes their growth with- 
out killing them. Zeylstra provisionally placed 
it in the group of Micrococcus. 
From these data it is probable that healthy 
O. nanella might be obtained by giving them 
less nitrogen and more phosphate of calcium. 
Unfortunately, however, the nitrogen manure 
acts as the strongest stimulant, under our 
climate, to induce them to become annual, and 
for many reasons it is most desirable to have 
cultures of annual generations. It is, there- 
fore, necessary to determine the amount of 
nitrogen and phosphate of caleium which will 
induce a sufficiently large percentage to be- 
come annual, but will not essentially heighten 
their liability to become diseased. 
In the summer of 1911, I made some pro- 
visional experiments which show that, by this 
method, there may be produced almost wholly 
healthy specimens with the normal stature of 
the dwarfs. In the first place, I found that 
every part of the stem, every single leaf and 
flower, may be normal or diseased, in response 
to external influences. In the young rosettes 
of rootleaves the first leaves were formerly 
always twisted; then came long-stalked nor- 
mal ones and, after these, the really abnormal 
leaves with broadened and shortened bases, 
which often killed the terminal bud before it 
could make a stem. By giving a large 
amount of phosphate of calcium, and as little 
nitrogen as possible, every one of the root- 
leaves could be grown healthy, with a stalk 
and a narrow wedge-shaped base. The same 
was the case with the leaves of the stem, and 
even with the flowers. The number of the 
abnormal ones could be brought down to a 
very few, thereby giving the whole plant the 
appearance of a healthy condition. All tran- 
sitions between diseased and normal dwarfs 
were to be seen in these cultures. 
Moreover, I have won beautiful healthy 
dwarfs by means of a cross from which the 
other parent was eliminated after the rule of 
the sesquireciprocal crosses.’ JI pollinated a 
3¢¢Ueber doppeltreciproke Bastarde,’’ Biol. 
Centralbl., 1911, T. 31, pp. 97-104. 
