willard: cranial nerves of anolis carolinensis. 47 



The long root {rx. cil. V.), from the nasalis division of the opthahnic, 

 is composed of both medullated and non-medullated fibers and joins 

 the ganghon on its dorsal side (Plate 5, fig. 15) about midway of its 

 length, many of its fibers immediately mingling with the ganglion 

 cells. The independence of the bundle is, however, preserved through- 

 out by the continuity of the non-medullated components of this root, 

 which passes across the dorsal side of the anterior half of the ganglion 

 and on into the large ciliary nerve, in which it appears for a con- 

 siderable distance as a lighter area in the cross section. These facts 

 do not preclude the possibility that many of the non-medullated 

 fibers end in the ganglion, nor that a part of the postganglionic bundle 

 of fine fibers takes origin in the ganglion. Further analysis of the 

 ciliary nerves discloses some of the coarse fibers of the short root in 

 each. The rest are of the smaller medullated variety and appear 

 to take their rise as peripheral neuraxons of the cells of the ciliary 

 ganglion, since they do not occur in the ciliary roots. 



In comparing Anolis with other Sauropsida we find that the arrange- 

 ment of roots, ganglion and ciliary nerves is that which Fischer ('52, 

 p. 117) describes as typical for reptiles. As an exception he mentions 

 Salvator merianae, where the trigeminal and oculomotor roots join 

 proximal to the ganglion. Other accounts agree with Anolis. Osawa 

 ('98, p. 602), in describing Hatteria, establishes another exception, 

 wherein the ganglion itself is not connected with the trigeminal nerve 

 by an independent root, but, if at all, through recurrent fibers, as in 

 the fowl, the ciliary rami from V joining the ciliary nerve distal to 

 the ganglion. 



Carpenter's (:06, p. 158) careful analysis of the ciliary ganglion 

 and its connections in the adult fowl is the only basis we have for a 

 comparison of histological features with conditions in birds. In the 

 fowl, the short root from the oculomotor being much the same as for 

 Anolis, one main ciliary nerve leaves this ganglion. This contains all 

 the well medullated fibers. Another small bundle, of feebly medul- 

 lated fibers, leaves the ganglion dorsal to the large one. A third 

 (small) ramus accompanies the other two; microscopic study, how- 

 ever, showed Carpenter that it contains no fibers from the ganglion, 

 but is merely a communicating ramus from the trigeminal, which 

 meets the ciliary nerve distal to the ganglion. The same ramus 

 sends some recurrent fibers back to the ganglion. Other fine rami 

 may be given off from the communicating ramus. All the trigeminal 

 elements are non-medullated. The ciliary ganglion itself is divisible 

 into a sympathetic and a cerebro-spinal part. 



