294 BIOLOGY OF THE LABORATORY MOUSE 



into the peritoneal cavity often gives rise to many small nodules of healthy 

 tissue convenient for reinoculation. 



Intrathoracic. — This cavity can be reached either through the diaphragm 

 or the intercostal spaces. The postoperative results are usually satisfactory. 



Intra -uterine. — Because of the small size of the os and the danger of tear- 

 ing it if inoculation through it is attempted, it has been found that exposure 

 of the uterus by abdominal operation, by either dorsal or ventral incision, is 

 preferable. The uterus provides an excellent site for transplantation. 



Intratesticular. — By maintaining pressure which keeps the testis in the 

 scrotum it becomes easily available as a site for implantation. If a more 

 delicate technique of transplantation is desired, an abdominal operation is 

 simple and effective! 



Intravenous.- The most accessible site is the tail vein in which inocula- 

 tions can easily be made. By proper care and experience this vein can be 

 used many times in a series of experiments without great difficulty. 



The eye. — In rabbits a satisfactory technique for implanting bits of 

 tumor tissue in the anterior chamber of the eye has been developed. In this 

 site vascularization appears to be rapid and extensive. Possibly as a result 

 of this factor alone or in combination with decreased specificity of reaction to 

 foreign tissue in that area, successful growth of homologous and even of 

 heterologous tissue has been reported. As yet this technique has been little 

 used in mice although it offers real promise. 



By application. — If desired a bit of tumor tissue may be applied to the 

 surface of an organ or tissue and be held in place there either by some adhe- 

 sive membrane such as that formed by collodion or by a single suture. This 

 method has the advantage of affording an opportunity to study surface reac- 

 tions between any two tissues. 



Material Used in Transplantation 



Since new tumors are constantly being discovered and are being used for 

 transplantation, it is impossible to make, at any one time, a complete and 

 permanent list of this material. 



On the other hand, it may be helpful in giving a picture of the opportuni- 

 ties for research in this field if some of the more interesting and commonly 

 used tumors are mentioned. 



Imperial Cancer Research Fund, London, England 



No. or Symbol Type of Tumor 



27 Adenocarcinoma of the mammary gland 



37S Spindle cell sarcoma 



