1886. ] MAMMALS IN THE SOCIETY'S GARDENS. 213 
the inferior maxilla. This cavity was filled with pus, but the abscess 
was limited by fibrous walls of considerable thickness. Feeling con- 
vinced that this was something more than a simple abscess, the 
bony walls were dissected and the sac removed and examined in 
detail. 
This cyst is represented of natural size in fig. 5. Projecting 
into its posterior aspect are portions of the fangs of two undeveloped 
teeth. This is sufficient evidence to show that we have to deal with 
a follicular cyst—that is, the walls of this sac are constituted b 
* the greatly distended follicle of one of the teeth, probably the 
incisor. From some cause or other suppuration had occurred, and 
led to the necrosis of the maxilla and absorption of the fangs of the 
The tunica vaginalis and testis of a Lamb affected with a congenital 
parenchymatous hydrocele. 
c, cremaster; d, tunica albuginea; e, epididymis; ¢, secreting-tissue of 
the testis. 
molar teeth: a remnant of one may be seen projecting into the cyst. 
The inferior dental nerve, as a mere thread, was closely embedded 
in the walls of the jaw on the outer side of the sac. The opposite 
maxilla was affected in a precisely similar manner. 
The last example of symmetrical disease I shall describe in this 
communication is a singular affection of the testes of a Lamb, 
which, so far as my knowledge of testicular disease extends, is unique. 
The lamb was thought to be ruptured on both sides, but on cutting 
into the supposed hernial sac a large quantity of fluid escaped, but 
no gut or omentum were found. The remaining testis was removed 
entire with its coverings and sent to me. The enormously dis- 
t ended outer covering (fig. 6) is the tunica vaginalis and testis cut off 
