Observations on Cyclopea in the Human Subject, etc. 271 



A thin bar of cartilage extended forwards, in the middle 

 line, from the post-sphenoid above the optic foramen to the 

 root of the snout. At the upper part of the base of the 

 snout two rudimentary nasal bones were found. They 

 articulated with the frontal. 



As already mentioned, the snout contained a single canal. 

 On dividing the snout close to its base the canal was seen to 

 communicate with two rudimentary nasal cavities. These 

 cavities were surrounded, except in front and above, by a 

 bony capsule. Their roof was formed by the thin bar of 

 cartilage already mentioned, and the dura mater which was 

 perforated by several small holes. The bone, with the dura 

 mater and cartilage, formed a rounded capsule, which was 

 little more than half an inch in diameter. On vertical 

 transverse section it was seen to contain a mesial septum 

 and two lateral cavities. The septum was well defined, and 

 reached to the floor of the cavity, but was not united with it. 

 The outer wall of each cavity contained some irregular spaces, 

 which might be regarded as rudimentary ethmoidal sinuses. 

 The septum, as well as the outer walls of the nasal cavities, 

 was well ossified. The two superior maxillary bones were 

 firmly united with one another, and both of them were 

 devoid of nasal processes. There were no indications of pre- 

 maxillary bones, and their absence was confirmed by an 

 examination of the teeth as there were no incisors, each 

 superior maxilla containing only three milk teeth — a canine 

 and two molars. Behind the superior maxillary bones were 

 found the palates, which were united with one another and 

 with the maxillary bones. They were considerably altered 

 in shape, and besides forming part of the hard palate, they 

 extended upwards behind the bodies of the superior maxillae 

 to form the posterior part of the floor of the orbital cavity. 

 The malars were normal, but no traces of the vomer or 

 lachrymals could be found. The two halves of the lower 

 jaw were separable, and contained the normal number of 

 teeth. The single orbital cavity was bounded above by the 

 frontal, below by the superior maxillse and palates, and on 

 each side by the malar and great wing of the sphenoid. 



