June 23, 1916] 



SCIENCE 



873 



tissues of various organs, frequently an 

 astonishing mixture of teratoid elements, 

 but all embryonic. These are also known 

 as atypical teratoids in distinction from 

 monsters, which are pre-natal malforma- 

 tions, and from typical (ripe or adult) 

 teratoids which also are not cancers, but 

 growths due to pre-natal disturbances, the 

 commonest form of which is the ovarian 

 dermoid. By Wilms they are called solid 

 embryomas or embryoid tumors in distinc- 

 tion from the typical teratoids, which he 

 calls cystic embryomas or simply em- 

 bryomas. 



The atypical teratoids grow rapidly, 

 metastasize freely and are commonest in the 

 early decades of life. In the typical tera- 

 toids the fetal fragments have grown with 

 the growth of the host. Although dwarfed, 

 they are as old as the individual out of 

 which they have come, i. e., they contain old 

 skin, old teeth, old bones, long hair, etc. In 

 the atypical teratoids the fetal fragments 

 are always very embryonic and probably 

 are never more than a few months old, or a 

 few years old, no matter how old the per- 

 son from whom they have been removed, 

 i. e., growth goes on in them independently 

 of the host. Moreover, these atypical tera- 

 toids always contain cancerous elements. 

 It is this latter type of tumor that I have 

 recently produced in plants. 



In the benign tumors, to return to ani- 

 mals, the tissues are arranged in a nearly 

 or quite normal fashion and the cells are 

 full grown, only much more abundant than 

 ihey should be. In the malignant tumors 

 the tissues are not only more embryonic, but 

 are arranged atypically, the cells having 

 lost a part or the whole of their polarity, 

 ■i. e., their orderly arrangement. Fre- 

 quently, they also show defective mitosis, 

 and very frequently polynuelear cells (the 

 so-called "giant cells") appear, owing to 

 fission and fragmentation of the nucleus 



without any corresponding cell division. 

 Lobed and cleft nuclei are very common in 

 cancers. They are also common in crown 

 gall. 



Cancers in addition to the malignant 

 cells contain a stroma or framework of con- 

 nective tissue and a system of blood vessels 

 and lymph channels by means of which 

 they are nourished, but the blood flow in 

 these vessels is not controlled by any vaso- 

 motor nervous system. Ordinarily cancers 

 do not contain any nerves, the associated 

 pain being due to pressure on outside 

 nerves. 



All of these tumors are imperfectly pro- 

 vided with blood vessels and are subject 

 to early decay, the resulting cavities, or 

 open wounds, being exposed to various 

 harmful secondary infections. In early 

 stages of growth these tumors are purely 

 local and may be removed surgically with 

 good prospect that they will not return. In 

 late stages these tumors exert a markedly 

 detrimental effect on the whole body, which 

 is visible as atrophy, anemia and cancerous 

 cachexia, and surgical interference is then 

 of little or no avail. 



The daughter tumors are produced from 

 the mother tumor in several ways, i. e., by 

 contact of a diseased area with a healthy 

 area, as for example, by tongue against lips, 

 or cheek against jaw; by invasive growth, 

 i. e., tumor-strands out of which the sec- 

 ondary tumors develop as in cancer of the 

 breast; by motile (creeping) tumor cells; 

 or finally, by cells or fragments dislodged 

 by the blood stream or the lymph stream 

 and carried to distant parts, where they 

 multiply. The carcinomas usually invade 

 by way of the lymphatics; the sarcomas 

 and the embryomas, by way of the blood- 

 vessels. When a tumor-strand can be traced 

 from the daughter tumors back to the 

 mother tumor they are called invasive 

 growths; when no such connecting link is 



