8 QUATERCENTENARY STUDIES IN PATHOLOGY 



The whole specimen was now injected with a four per cent, formalde- 

 hyde solution, and placed in a solution of the same strength for two days. 

 Thereafter the specimen was frozen and a sagittal section made, just to the 

 left of the middle line, through both foetus and tumour. 



The mesial section of the foetus, except for the head condition, 

 presents normal appearances (Fig. 4). The body of the hyoid bone 

 shows a centre of ossification, and is at the level of the middle of the 

 body of the third cervical vertebra. The cricoid cartilage lies at the 

 level of the disc between the fourth and fifth cervical vertebrae, while the 

 upper border of the manubrium is opposite the first dorsal vertebra. 

 The trachea bifurcates on the disc between the third and fourth dorsal 

 vertebrae. Thus the various structures do not lie at a lower level than 

 usual. The thyroid and thymus glands are well developed. There is no 

 abnormality of the heart. Dark green meconium distends the large 

 intestine, microscopically, this shows the usual constituents of meconium 

 including delicate lanugo hairs. The bladder is distended, reaching to 

 the umbilicus. 



Coming to the tumour mass itself we can obtain a general idea of its 

 nature by noting the appearances presented by the sagittal section 

 depicted in Fig. 4. The section is made just to the left of the middle 

 line and the right face is seen viewed from the left. The lower part of 

 the section is of a dark red colour, soft and vascular, while the upper 

 part, lighter in colour, varies in appearance and consistency. In the 

 centre is an irregular piece of bone in which two dental sacs are seen cut 

 across. Above and in front of this bone is fibrous tissue containing a 

 large lobule of fat, and covered by normal skin. Passing up into the 

 stalk of attachment of the tumour is a large serous cavity containing a 

 closed knuckle of bowel. The lower part of the section is largely made 

 up of rudimentary nervous tissue, in which there is a large cyst with a 

 thin smooth wall. Just above this cyst there is a degenerate and 

 collapsed eyeball lined by dark pigment. 



Detailed Structure of Tunnour. 



Each half of the tumour was now carefully and completely dissected. 

 Many pieces of the various tissues were removed for microscopical 

 examination. These pieces were embedded in celloidin, and sections cut 



(182) 



