EYES AND NEURAL GLANDS IN CYCLOSALPA. 



2O5 



is irregularly conical rather than flat and shows no sign of 

 division into right and left limbs, approaching in form and struc- 

 ture the eye of the true Salptf, for example S. rnnciuata-fnsifonnis. 



d. 



,j i 



a.. 



p- 



a. 



9. 



Outline drawings of ganglia and eyes of salpa. 



a. anterior ; d. dorsal ; Gg. = ganglion ; />. = posterior ; r'. = ventral ; x. 

 indicates in each case the same region of the eye. 



FIG. A. Dorsal view of ganglion and eye of a solitary salpa. The horseshoe- 

 shaped eye is above the ganglion, with the ends of the horseshoe pointing forward. 



FIG. 1). The same seen from the right side. 



FIG. C. Ganglion and eye of an immature chain Cyclosalpa pinnata. In an earlier 

 condition this eye was horseshoe-shaped and lay horizontally on the dorsal surface of 

 the ganglion, resemblimg Figs. A and B. It has now rotated forward and upward 

 through an arc of about 90. That surface of the eye which was dorsal when the 

 eye was horizontal is now anterior. 



FIG. D. The same eye and ganglion as those shown in Fig. C., but here seen from 

 behind. The eye is in the form of a flat plate, ihe hollow of the horseshoe having 

 become filled with cells. 



FIG. E. The eye and ganglion of an adult, chain Cyclosalpa pinnata, seen from 

 the right side. The eye has shifted 90 still further forward and is again horizontal, 

 but with its former posterior portion now anterior. (Cf. Plate VII., Fig. 3. ) 



FIG. F. Dorsal view of the same eye and ganglion as those shown in Fig. E. 

 The eye is seen to be split posteriorly into two limbs, being again horseshoe-shaped. 

 (Cf. Plate VII., Fig. 4.) 



