200 Proceedings of the Royal Irish Academy. 



Tcjus teguixin. The ligament consisted of a band connecting the 

 internal part of the femoral notch with the anterior portion of the 

 internal semilunar cartilage. 



Iguana rliinolophis. Same as in preceding case ; was a strong, 

 fibrous band, quite separate from the crucial ligaments. 



Ameiva lineolcda. Same as before; was a flat membrane. A sort 

 of horizontal septum. 



Am/pliiboluTus harhcdus. Same as before ; the internal semi-lunar 

 cartilage was attached to the internal condyle by a band of synovial 

 membrane. 



Chameleo ndgaris. I examined two specimens of this reptile, in 

 both of which the ligament was absent. 



Moloch horridus. Same as in Amphilolurus larlaUis. 



Ecfliymotes oMusirostris. A mere thread, attached like the pre- 

 ceding ligament ; there was a second band of some width going to the 

 internal condyle. 



Crocodilus hiporcatus. This was a very young specimen, the liga- 

 ment existed as in the lizards. 



Tatusia liirsida. The ligament formed a complete septum, was 

 T-shaped, and formed the sheath of the extensor tendon. 



Sheep. Formed a complete septum, and was roofed in on the 

 external side by the synovial membrane which formed the sheath of 

 the extensor tendon ; there were vessels on its surface from the exter- 

 nal articular and azygos arteries. 



lutra vidgaris. The ligament was T-shaped, and formed a com- 

 plete septum. 



Nasna narica. It formed a complete septum, the synovial mem- 

 brane being reflected over the marsupium, thus roofing in the cavity. 



Canis familaris var. Was composed of several threads containing 

 fat, and a vessel from the superior internal articular artery. 



Ursus lasiotus. Was loaded with fat; did not form a septum. 



Ursus Ilimalayanus. It formed a complete septum, and at the 

 posterior border was traversed by a large branch from the azygos 

 articular artery. 



Preslytes comatus. The ligament was absent. 



Cercopitheeus griseo-viridis. It existed as a coarse thread. 



Cercopiiliecus mona. In the right limb the ligament was a mere 

 thread, in the left limb it was double, one thread being attached to 

 the external condyle. 



In conclusion I wish to di'aw attention to some points which 

 anatomists have, I think, stated wrongly, or passed over without 

 notice. 



1. Luschka says, " That only exceptionally does it form in man a 

 membranous sagittal septum." Now, it appears to me that the com- 

 plete septum is somewhat more than an exception, seeing that nearly 



