chap, xxxvi.] LIGAMENTUM PECTINATUM. 299 



to the choroid membrane is the supra-choroidal 

 tissue. 



416. There are blood-vessels in the sclerotic, which 

 belong to it : they are arterioles, capillaries, and 

 veins ; in addition to these are the vascular branches 

 passing to and from the choroid. 



417. III. The li gam en turn pectiiiatiun 

 iridis (see Fig. 152) is a conical mass of spongy tissue, 

 joining firmly the cornea and sclerotic to the iris and 

 ciliary processes. It forms an intimate connection, on 

 the one hand, with the junction of cornea and sclerotic, 

 and on the other, with that of the iris and ciliary pro- 

 cesses. This ligament is composed of trabeculse and 

 lamellae of stiff elastic fibres, forming a continuity, on 

 the one hand, with the lamina Descemeti of the cornea 

 and the elastic fibres of the sclerotic, and on the other, 

 with the tissue of the ciliary border of the iris. The 

 trabeculae anastomose, so as to form a honeycombed 

 plexus, and the spaces in this plexus are lined 

 with a layer of flattened endothelial cells, directly 

 continued from the endotheliuin of Descemet's mem- 

 brane, on the one hand, and with the layer of endo- 

 thelial cells covering the anterior surface of the iris, 

 on the other hand. In some mammals, the spaces 

 in the ligamentum pectinatum at the iris end are 

 very considerable, and are called the spaces of 

 Fontana. 



The interlamellar and interfascicular lymph- 

 spaces of the sclerotic form an intercommunicating 

 system. 



The nerves form a dense plexus of non-medullated 

 fibres in the tissue of the sclerotic (Helfreich). 



At the point of junction of the cornea and sclerotic, 

 but belonging to the latter, and in the immediate 

 neighbourhood of the ligamentum pectinatum iridis, 

 is a circular canal the canal of Schlemm; this is 

 lined with endotheliunij and is considered by some 



