192 
HISTOLOGY OF ANIMALS. 
human subject, represented in Fig. 143. In fatty 
tumours, the fat is usually more or less yellow, and 
contains few if any vessels which bleed on its removal 
or when cut ; hut it sometimes happens that the mass 
is of a red colour, and contains a very large amount 
of blood. A tumour of this character, removed after 
death from the mesentery of a child, by Mr. Pittard, 
formerly one of our students, had at first sight an 
appearance like that of malignant disease, and when an 
incision was made into it, a large quantity of blood 
escaped. Its true nature was only ascertained by 
microscopic examination, when it turned out to be 
nothing more than a mass of adipose tissue, and 
although it has been preserved in spirit and exposed 
to the light for the last two years, it still retains a 
portion of its red colour. 
