PLATE IX. 
LETTERING ON THE FIGURES. 
acr.. . . acrorhagia. p.m. . . pennon muscle. 
ect. . . . ectoderm. sph... . sphincter muscle. 
end.. . . endoderm. t  . . . tentacle, 
m. . . . mesoglea. t  . . . testis in figure 3. 
Oh 6 6 o yin v . . - vesicle. 
p.b.m.. . parieto-basilar muscle. 
Cystiactis tuberculosa (Quoy et Gaim.). 
Figure 
1. Vertical section through sphincter muscle, x 75. 
2. Transverse section through part of a tentacle, showing the ordinarily ectodermal muscle become 
mesogleeal in this species, x 75. 
8. Transverse section of the proximal portion of a mesentery. Three mother cells of spermatozoa are 
seen, x 75. 
Actinioides Spenceri, n. sp. 
4. Vertical section through the acrorhagia of a contracted specimen, x 75. 
5. Transverse section through the body-wall and proximal portion of a mesentery, x 75. 
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