16 ANATOMY OF ASTRANGIA. 
PLATE IV. 
INTERNAL ANATOMY. 
Fig. 1—Section (horizontal) showing the tentacles retracted but not withdrawn from sight. 
a,b, c. Tentacles. d. Septa. e, f. Wall separating the bases of the tentacles. g. Wall con- 
necting the axial ends of the septa. h. Ciliated passage from stomach into the lower cavity of the 
body, in which mesenteries are found. 
Fig. 2.—An extremity of a tentacle showing the terminal cluster of nematocysts (a) and lateral 
clusters (b). Tentacle somewhat retracted. 
Fig. 3.—Lateral view of a tentacle. 
a. Terminal cluster of nematocysts. b. Lateral clusters. c. Muscular (longitudinal) fibres 
which move the tentacles. d. Septa. 1(?), f Superficial epiblastic cells. 
Fig. 4.—An enlarged end of a tentacle showing the cluster of terminal nematocysts (a) and the 
lateral clusters (b). The tentacle is contracted ? 
Fig. 5—A similar tentacle elongated. Lettering as in Fig. 4. 
Fig. 6.—A view of a section (horizontal) in which the opening (h) is contracted. Lettering as 
in Fig. 1. 
Fig. 7.—Distal extremity of a contracted tentacle. 
