332 Proceedings of the Royal Irish Academy. 



LIII. — On some Anomaiotjs Stetjcttjees nsr Huitan Anatomy. By 

 J. F.Knotx, F.R.C.S.I., L.K.Q.C.P.I., Demonstrator of Anatomy, 

 Eoyal College of Surgeons, Ireland. 



[Read, December 8, 1879.] 



The anomalous structure to which I have the honour of calling the 

 attention of the Members of the Royal Irish Academy was discovered 

 in the dissecting-room of the School of the Eoyal College of Surgeons. 

 I had been assisting in the dissection of the spinal cord and the 

 ligaments of the vertebral column of the subject on which it was 

 found. Those of the two upper vertebrse were left till the last, as I 



Fig. 1 represents tlie parts, and gives a good idea of the connexion of tlie ligament 

 in question with the upper margin of the transverse ligament — a, superior 

 appendix of cruciform ; h, upper part of transverse ligament ; c, Hgamentum 

 transversale occipitale. 



had already intended to examine them with special attention. The 

 posterior part of the occipital bone had been removed in the course of 

 the dissection, as well as the laminae of all the vertebrae. The 

 posterior common ligament of the spine had been examined, and its 

 prolongation into the cranium through the foramen magnum traced 

 along the upper surface of the clivus as far as the upper margin of 

 the dorsum sellce and the posterior clinoid processes. After the removal 

 of this structure the apparatus ligamentosus was defined, but no 

 peculiarity was observed to exist either in its structure or attach- 

 ments. This having been in its turn taken away, and the subjacent 

 bursa examined, I proceeded to define the outlines of the crucifonn 



