PATHOLOGY: E.F.SMITH 
447 
6. Possibility of the existence of carcinomas and of mixed tumors in 
plants.— Slides were shown suggesting that it is experimentally possible, 
to induce the prohferation of glandular tissue and the epidermis (skin) 
of plants by bacterial inoculations, but so far no metastases have been 
obtained. This whole subject, however, is yet in its infancy and fur- 
ther reports will be made from time to time as results are obtained.. 
7. Production of embryonal teratomata. — Last winter I discovered that 
when growing plants are inoculated in the vicinity of dormant buds a 
new type of tumor is produced. This tumor bears on its surface dimin- 
utive abortive shoots (vegetative or floral), and in its interior, along 
with the cancer cells, numerous fragments of embryonic tissues, variously 
fused and oriented, often upside down and curiously jumbled. These 
tumors have never been seen by the writer in nature or at least if seen 
not recognized as crown gall tumors, but undoubtedly we shall now find 
them.^ These tumors have all been produced with Bacterium tumefaciens 
plated from an ordinary sarcoma-like tumor of the hop received from the 
Pacific Coast 8 years ago. The plants chiefly experimented on have 
been Pelargonium, Nicotiana, Lycopersicum, Citrus, and Ricinus. 
All of these and some others (Mangifera, Allamanda, etc.) have yielded 
teratoid tumors from inoculations in leaf axils. 
The inoculated tobacco also developed secondary teratoid tumors at 
a distance from the primary tumor in both stems and leaves, i.e., tumors 
bearing numerous diminutive and abortive shoots, which at longest 
have lived but a few months. In other words, like the secondary 
tumors on the Paris daisy they have repeated the structure of the parent 
tumor but this time that which is repeated is not a sunple sarcoma 
developed out of fundamental tissues but a complex tumor comparable 
to the embryonal teratomata or atypical teratoids occurring in man. 
Many attempts have been made in recent years to produce such tumors 
in animals but hitherto all experimenters have failed. Monsters, it is 
true, have been produced repeatedly by fragmenting eggs, and in other 
ways, but always they have been typical teratoids, never cancers. 
However, the most striking result I have obtained is yet to be told.: 
All the embryomas previously mentioned were obtained by making 
my bacterial inoculations in the vicinity of dormant buds (totipotent 
anlage) which were then apparently torn by the rapid growth of the 
tumor, the fragments being variously distributed in the tumor and there 
stimulated to develop, the result being embryonic growths of extremely 
variable size but all referable to the original disturbed shoot-anlage. 
If, however, inoculations are made in regions not known hitherto to 
