IV. OF RAN A PIPIENS. 51 



FIG. 6. Right eye seen from below. III. Motor communis giving branches to rectus inferior and rectus 

 internus, also to the, obliquus inferior muscles. V. Branch of trigeminus to the external rectus, abducens. 



FIG. 7. Tadpole, showing general form of the chord previous to the development of legs. 



FIG. 8. Tadpole, showing changes in the form of the chord after the development of the legs and 

 before the absorption of the tail. 



FIG. 9. Tadpole, showing the temporary branches of the vagus ; a, branch of vagus giving off dorsal 

 branch, b, distributed to the fin of the tail, and the lateral nerve, c ; d, branches of vagus passing along 

 the branchial arches. The descending branches along the side of the abdomen are spinal nerves, which 

 escape from beneath the muscles, and pass beneath the lateral nerve, but do not communicate with it. 



FIG. 10. Ganglion of the sympathetic nerve, a, trunk of the third spinal nerve ; i, muscular and 

 cutaneous portion ; c, branch to the ganglion, dividing into ascending and descending filaments, which 

 become separated from each other, and inclose ganglion cells ; <2, d, sympathetic fibres, which extend 

 through the ganglion, in passing which their filaments separate and include ganglion cells. 



s 



FIG. 11. A, olfactory pouch ; B, olfactory nerve ; C, olfactory lobe ; D, cerebral lobes ; V, V, orbitar 

 branches of the trigeminus, crossing the olfactory nerve, sending filaments to the olfactory pouch, and 

 terminating in the skin of the upper lip. 



