Dec. 22 ,1923 
Intracellular Bodies in Wheat Rosette 
607 
that they may be a micron or less in size in their earliest stages, since 
globules of these smaller dimensions may be seen in some cells. Studies 
made thus far indicate that the size of the bodies increases with the age 
of the host cells including them. Further, typical bodies which can 
be definitely identified have not yet been observed in the very young 
cells of the young central and lateral buds. The minute bodies which 
are suggestive of an early stage of the large bodies have been found in 
cells a little distance back from the youngest cells, and from this latter 
region back into the older cells, the bodies seem to increase gradually 
in size until the large sizes are reached in the oldest cells of the leaf 
sheaths and crown. 
The bodies occur ,in various relations to the cell nuclei as shown in 
Plates 3 to 8. In the majority of cases the bodies occur either free from 
or in more or less close contact with the nucleus. Occasionally, however, 
they may be found partially or completely surrounding it, as shown in 
Plate 7, Figs. 1, 3, 4, and 9. 
The contents of the bodies seem to be of a rather homogeneous struc¬ 
ture containing many large and small vacuoles. The large vacuoles 
usually are very conspicuous when viewed through 4 mm. objectives, 
but the small ones are visible only when high resolving lenses are used. 
Studies made with carefully stained sections from killed and fixed tissues 
indicate that the bodies are surrounded by a membrane and there is a 
strong suggestion that they consist of alveolar protoplasm. 
The majority of the intracellular bodies in wheat studied thus far 
show no detail in their vacuoles. However, in a few cases in both fresh 
and fixed materials, these vacuoles have contained granulelike and also 
elongated bodies. Structures suggesting nuclei have occasionally been 
found (PI. 8, Figs. 4, 5, and 8), but these are neither consistent nor definite 
in the material studied. In many fixed and stained preparations, the 
vacuoles are surrounded by densely staining rings as shown in the 
various plates. As yet the intracellular bodies have not been observed 
to possess definite independent movement. In fresh, unstained material 
they have been observed to move from place to place in' the cell, but 
this movement was attributed to the distinctly evident streaming move¬ 
ment of the surrounding cytoplasm of the host cells. 
Examinations of fresh material in sterile water mounts have occasion¬ 
ally shown moving granulelike bodies and also elongated, flexible bodies 
in the vacuoles of the larger intracellular bodies as shown in Plate 6. 
These intravacuolar bodies usually are in motion when first examined 
and remain so for periods of from 36 to 42 hours. Then all movement 
seems to stop. The granules and elongated bodies have been noted only 
occasionally, but it has been rather evident that, when a few are found, 
many others may be discovered in the same plant and to some extent 
in other plants grown under the same conditions. A few structures 
resembling those in the vacuoles of fresh material have been found in 
fixed and stained material, but it has not been possible to determine 
their exact nature. In the specimens of fresh material, the movement 
of the granulelike bodies could be interpreted as typically Brownian. 
The movement of the elongated bodies, however, seems to differ from 
the ordinary Brownian type. The movements of these latter forms are 
more like those which have been described for the mitochondria. 
From the studies made thus far the majority of the wheat cells con¬ 
taining intracellular bodies show no marked differences from the cells 
