Inheritance of Mutation in the Common Foxglove. 5 1 
petals. 1 Several intermediate forms occur, and the various modifi¬ 
cations which form a progressive series will be most easily exhibited 
in the accompanying table. 
Modifications of the Corolla. 
(a). Upper lip. 
1. The upper lip may be wholly wanting. The posterior part 
of the tube is then reduced to a mere rim with an even concave 
outline (see fig. 3). 
The upper lip may be represented by :— 
2. Two projections on the posterior rim of the tube (see fig. 4). 
3. Two filaments presenting all stages between 2 and 4 (see 
fig. 5). 
4. Two filaments equal in length to those of the ordinary 
stamens, and bearing a one-lobed anther which forms normal pollen 
and dehisces when ripe (see fig. 6). 
5. Two stamens bearing bilobed anthers similar to those of 
the ordinary stamens. (Only observed in very few cases). (See fig. 1). 
1 This extreme stage does not appear to have been present in 
de Chamisso’s plant. 
Text-figs. 1 — 11, shewing various forms of lieptandra flowers seen in different 
views. All the figures are taken from full-sized flowers, except figs. 1 and 2. 
1. Arrested flower seen from above with calyx and nine stamens. 
2. Arrested flower seen from the side showing an upper lip of two small 
petals and seven stamens. Calyx removed. 
3. Flower seen from the back showing seven stamens. The lower lip 
of the corolla is represented by three stamens, distinguished from the androe- 
cium proper by the divergent anther lobes ; upper lip wholly suppressed, the 
posterior side of the flower tube being reduced to a mere rim with an unbroken 
concave outline. Calyx removed. The speckled anthers show that if the 
corolla had been normal, the spots would have been coloured red. 
4. Flower showing three small projections on the posterior rim of the 
flower-tube which probably represent the rudiments of the upper lip, and the 
posterior stamen ; otherwise as fig. 5. 
5. Flower showing a rudimentary upper lip in the form of two filaments; 
otherwise as fig. 6. 
6. Flower in which the upper lip is represented by two stamens, each 
bearing a half anther. Calyx removed. Seen from the front. 
7. Flower with upper lip of two completely fused petals, (a). Seen 
from the side. ( b). Seen from above. 
8. Flower with upper lip of two partly fused petals. The three structures 
representing the lower lip still bear anthers, but they are gradually becoming 
petaloid. Two outgrowths—the ladnulce corallines of de Chamisso—are seen on 
either side. Calyx removed. Seen from the front. 
9. Flower showing an upper lip of two partly fused petals. The 
central one of the three structures representing the lower lip has become more 
distinctly petaloid. Calyx removed. Seen from the front. 
10. Later stage in reversion. ( a). Seen from the front. ( b ). Seen 
from the side. The speckling on the anthers has been omitted here and in fig. 
11 . 
11. Later stage still. Seen from the front. 
