134 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



expanded portions of these tubes. From it runs forwards 

 a large canal, also dilated to about 05 cm. in diameter : 

 this is probably Ewart and Mitchell's H.M.4 to H.M.S. 

 A smaller round cyst, about 1 cm. in diameter, projects 

 out from the antero-median surface of this large cyst, 

 and a large cyst, with semi-transparent walls, and about 

 2'5 cms. in diameter, lies on the floor. With these 

 exceptions, the dorsal surface of the head is normal. 



The cavities contain a transparent, sticky fluid, 

 which is probably very similar to that secreted by the 

 sensory canal epithelia. Within them are the intra- 

 cystic growths, and these are very peculiar in nature. 

 All the dilated canals contain these growths, but in some 

 of them, the right supra-orbital on the dorsal surface, 

 for instance, the growths are small, round, worm-like 

 bodies, slightly yellow in colour, and translucent. They 

 are smooth and are rarely branched or lobulated. Some 

 of these bodies are represented in fig. 2, PL IV. 



The other growths are white in colour, fairly hard, 

 sometimes with a peculiar glistening appearance, and of 

 the most extraordinary shapes. Two of the larger ones 

 are represented in PL IV. The largest is about 8 cms. 

 in length and about 1*5 cm. in diameter at its widest 

 part. The two growths represented were attached to the 

 internal wall of the cyst by very delicate pedicels, the 

 remains of which can be seen in the photograph, and 

 they were very easily detached. They were taken from 

 the expanded part of the infra-orbital canal, and one lay 

 in each of the large vesicles, but the larger of the two 

 projected into the hyomandibular canal. The other 

 dilatations on the ventral surface contained only the 

 smaller yellow bodies. It will be seen from the photo- 

 graph that the larger growths are produced into 

 appendages, lobes, and that they are racemose or 



