Ward — Sipunculus. 



PLATE III. 



Fig. 23. Transverse section of hypodermis of tentacular fold with sensory cells. 

 Weigert's picrocarmine. Zeiss apochr. 4 mm. Oc. 8. X 725. 



" 24. Transverse section of brain. Plane of section shown in Figure 22, Plate 

 II Grenacher's alcoholic borax carmine- Zeiss 1. A. X 50. 



" 25. Transverse section of brain. Plane of section shown in Figure 22, Plate 

 II The sention was cut somewhat obliquely, and the right half lies 

 posteriad. Grenacher's alcoholic borax carmine. Zeiss 1. A X 50. 



" 26. Transverse section of body wall passing through the canal of the cere- 

 bral organ at about the middle of its course. The left of the figure 

 is dorsal. Hamann's carmine Zeiss 1. A. X 50. 



" 27. Transverse section of the cerebral organ: only one half is represented, 

 and but a small section is drawn in detail. The cerebral canal begins 

 at the angle near the number 27, and extends forward at right angles to 

 the surface marked eta. The transition from the cuticula of the cere- 

 bral organ to that of the canal is marked by a t- Czokor's cochineal 

 and picric acid. Zeiss apochr. 4 mm. Oc 8. X 510. 



" 28-31. GangHonic cells. Zeiss apochr. 4 mm. Oc 8. X 510. Fig. 28, Class 

 III. Fig. 29, Class II. Fig. 30, Nuclei of Class I. Fig. 31, Class I. 



" 32. Oblique section through a ganglionic cell of Class II., showing the 

 regular arrangement of the paramitone. Hamann's carmine. Zeiss 

 apochr. 4 mm. Oc. 8. X 725 



