GEROULD. — Caudina. 
ag. ere. 
aq. 7. 
el. gn. 
cp. sph. 
cta. 
en. r. 
en’th. 
eth. 
Vpn. r. 
mad. 
PLATE 1. 
ABBREVIATIONS. 
Circular water canal. mu.tr. Transverse muscles of the 
Radial water canal. body-wall. 
Ganglionic cell. nN. Nervous tissue. 
Spheruliferous wandering n.7.ex. External band of the radial 
cell. nerve. / 
Cuticula. n.r.i. Internal band of the radial 
Radial epineural canal. nerve. 
Endothelium. pa. gen. Genital papilla. 
Epithelium. sep. Connective-tissue partition. 
Hyponeural canal. sng.r. Radial haemal vessel. 
Madreporic body. tbl. mu. Tubules composed of mus- 
cle fibers. 
Cross section through one of the radial nerves and accompanying 
vessels. XX 360. 
Cross section through the body-wall near the region of the tentacles. 
X 330. 
Portion of circular water canal with stone canal and madreporic body. 
x 12. 
Oblique view of anterior extremity of the body. X 6. 
Cross section of the body-wall through a radius, showing muscle 
tubules. X 118. 
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