THE EYE AND ITS APPENDAGES. 



339 



hollowed out within the cement-substance, which consists of the 

 large lacunae or corneal spaces between the lamellae and the 

 small canaliculi extending from the former as fine branching tubes. 

 The corneal corpuscles are usually applied to one wall of the spaces, 

 which they by no means 



completely fill, while their FIG. 365. 



processes extend within the ; ^^V... , ~ : V 



branching canaliculi. In SraSx^K ;< ;" 



addition to the corneal cor- 

 puscles, wandering cells, 

 together with the tissue- 

 juices, occupy the spaces 

 and canaliculi. 



The posterior limiting 

 membrane, membrane 

 of Descemet, or poste- 

 rior elastic lamina, ap- 

 pears as a clear homoge- 

 neous band at the inner boundary of the cornea, sharply defined 

 from the deepest layers of the substantia propria and clothed on its 

 inner surface by endothelium. The membrane differs from the cor- 

 responding anterior lamella in its less intimate attachment with the 



FIG. 366. 



Corneal spaces from calf; silver preparation. 



Corneal spaces from calf; exhibited spaces in positive picture after interstitial silver injection. 



fibrous stratum and in possessing the greatest thickness (10-12 /*) at 

 the periphery. After prolonged maceration or treatment with suit- 

 able reagents the resistant lamina is separable into a number of thin 



