542 T. A. STEPHENSON 
The Endocoelactaria form a decided small line apart, 
and with very distinct characters (see p. 522), and it seems 
inevitable to give them a group to themselves. Since they 
seem clearly post-Halcampid, this group must come under 
Nynantheae, not outside it; and is distinct enough from 
other Nynantheae to require no further subordination. 
This leaves the Mesomyaria and Endomyaria, or 
main mass of forms. It has been part of the purpose of this 
paper to show that this main mass does fall into two chief 
sets, followmg two great lines of tendency, and these two 
lines I propose to embody in the two sub-tribes named. The 
Mesomyaria contains the forms classified in Part I, the creatures 
with acontia and mesogloeal sphincters and so on; the Endo- 
myaria contains those with no mesogloeal (and typically an 
endodermal) sphincter, no acontia, and often with vesicles, 
frills, &¢.—for more detail of Endomyarian and Mesomyarian 
tendencies see pp. 560 et seq. The Endomyaria contains the 
whole of the old Stichodactylinae (save soft corals) and part of 
the Actininae, and if those names be still used it should be 
only as subdivisions of this group. 
For most of the matter supporting the various suggestions 
made in this section, reference should be made to the sections 
on evolution and on special sets of forms, and other parts, 
both in this paper and in Part I. 
It now remains to allocate the families listed on p. 587 to 
their respective groups. 
1 PROTANTHEAE. Gonactiniidae. 
2. PTYCHODACTEAE. Ptychodactidae. 
3. NYNANTHEAE. 
A. ATHENARIA, Halcampidae, Ilyanthidae. 
B. Enpocornactrarta. Halcuriidae, Actinernidae. 
C. Mersomyarta. Diadumenidae, Phelliidae, Flosmarinidae, Mar- 
supiferidae, Metridiidae, Chondractiniidae, Actinoscyphiidae, 
Sagartiidae, Choriactidae, Paractidae. 
D. Enpomyarta. Condylanthidae, Myonanthidae, Andresiidae, 
Actiniidae, Aliciidae, Phyllactidae, Minyadidae, Phyman- 
thidae, Heteranthidae, Stoichactidae, Actinodendridae, 
Thalassianthidae, Homostichanthidae, Aurelianidae. 
Discosomidae and Corallimorphidae go to Madreporaria, 
