266 THE RETINA. 



containing a nucleus, and having its stalk prolonged inwai'ds, 

 like the filaments of the rods. 



The white cellular layer is composed of three strata — an 

 outer, an intermediate, and an inner. The outer consists of 

 the ovoidal nucleated appendages of the cones ; of the ovoidal 

 appendages of the rods wliich have such bodies attached ; and 

 of similar bodies in which the conical appendages of the 

 other rods terminate. The intermediate presents a semifluid 

 granular basis, through which numerous filaments pass from 

 the outer into the inner stratum, in a direction perpendicular 

 to the surfaces of the retina. These filaments, wliich issue 

 from the outer stratum, are, firstly, the prolongations of the 

 filaments which proceed from the nucleated appendages of 

 the cones ; secondly, the prolongations of the filaments which 

 proceed from the ovoidal appendages of the rods possessing 

 such ; and, thirdly, filaments proceeding from the inner extre- 

 mities of the ovoidal bodies, which are connected with the 

 filamentary terminations of the conical appendages of the 

 other rods. The inner stratum also consists of two sets of 

 ovoidal bodies, each of the first connected with some one of 

 the prolongations of the filaments of the cones, and giving off, 

 at its opposite end, a similar filament ; while those of the 

 second set, similarly formed and provided, are connected with 

 the prolongations of the filaments of the rods. 



Towards the circumference of the retina, many rods may be 

 found, connected by the filaments proceeding from their ovoidal 

 bodies with a single filament passing into the inner stratum. 

 This connection never occurs between the filaments of the 

 cones, which are thus invariably independent of one another. 



There may generally be found a branch passing obliquely 

 inwards from some part of the filament of the cone and rod, 

 in its passage through the intermediate stratum, or from the 

 ovoidal bodies of the inner stratunx 



The grey cellular layer consists of a fine granidar basis, 



