598 REPORT—1904. 
and the bacteria, and it is because of these far-away resemblances that I shall 
make a new order for the organism, placing it intermediate between the bacteria 
on the one side and Microsporidia on the other. 
Diseases in lower animals due to Microsporidia are frequently characterised by 
great virulence and well-marked epidemic tendency. Thus it 1s, for example, in 
the Pébrine disease of silkworms and in Lymphosporidiosis of brook trout. 
Singularly enough, these diseases give rise to characteristic lesions in the skin and 
body-wall analogous, perhaps, to the vesicles and pustules of small-pox. 
The first appearance of the organism in the human skin is a minute homo- 
geneous spherule, as solid apparently as a sperm head in the cytoplasm of an egg. 
This enlarges and differentiates into two substances—one destined to give rise to 
the multiplication elements or gemmules, the other forming an enveloping matrix. 
The organism increases in size until it is larger than the cell nucleus. The 
gemmules repeat the cycle again and again, thus giving rise to auto-infection of 
the vaccinia type. 
In later stages the gemmules enter the nucleus, where they develop into two 
kinds of structures; one sort has a central residual mass with peripheral points, 
the other has a central mass with large surrounding matrix. There is reason to 
believe that these structures are connected with the sexual generation, the former 
being a male, the latter possibly a female gametocyte. This point, however, 
I found impossible to solve, and must leave it for further research. 
From the structure, which appears like an egg-cell, arises the pan-sporoblast 
stage. The young sporoblasts appear as exquisitely minute points of deeply 
staining substance throughout the matrix, which envelops the central mass men- 
tioned above. These increase in size and ultimately give rise to spores. Meantime 
the nuclear membrane has been ruptured and the sporoblasts are liberated. The 
spores form in the same way as the gemmules, but differ from these in being 
hollow spherules five-tenths of a micron in diameter. 
Spores may be found scattered in the cytoplasm and in the nucleus, but it is 
only in the latter that they can develop further. In the nucleus they grow into 
structures somewhat like the primary sporoblasts, but they are readily detected. 
This, so far as I know, is unique among Protozoa, although analogies are found in 
other groups of animals. 
There are thus three modes of auto-infection—viz., gemmule formation, sporula- 
tion from the primary sporoblast, and from the secondary sporoblast. All of 
these together are none too many to account for the rapid spread of the organisms, 
which in a very few days may infest the entire human skin. 
6. Certain Biological Aspects in the General Pathology of Malignant 
New Growths. By J. A. Murray, MB. 
From time to time biologists have turned their attention to some of the 
problems which cancer presents, but their contributions to the subject have not 
been accepted as final. The limited scope of the individual investigators may 
well be the principal reason for this want of correlation between the different 
lines of work. The investigations of the Imperial Cancer Research Fund have 
been directed by the conviction that it is essential, if progress is to be made, that 
the facts from widely distinct fields of inquiry should be focussed on the essentials 
of the problem, and conclusions apparently warranted by one set of observations 
must be controlled by all the others. 
The following different lines of inquiry seem to be of importance at present: 
1. Pathological-anatomical, including gross anatomy, as well as histological 
and cytological investigations. 
2. Zoological distribution, including ethnological distribution. 
3. Statistical investigations—age distribution in correlation with zoological 
distribution. 
4, Experimental investigations. Transmissibility. Powers of growth of 
normal and malignant tissue. 
