PLATE XII. 



SOLENASTR.EA HYADES (Dana). 



Fig. 84. — Transverse section through the lower region of the same polyp as that from which figs. 80 and 81 are 

 taken. At this level the entocoelic and exoccelic septa are all fused in the middle to form the columella. 

 Twenty-four distinct loculi occur, each containing a single mesentery. The outer indentations of the 

 locular walls correspond with the strong granulations on the faces of the septa. X 100. 



Fig. 85. — Transverse section through a septal loculus, ahout the middle of the length of the polyp. The filament of 

 the included mesentery is somewhat incipient in character, not being sharply separated from the 

 stomodfeal endoderm. The skeletotrophic endoderm is comparatively narrow, and the calicoblast layer 

 is well developed in places. X 300. 



Figs. 86-90. — Sections of a bud polyp taken at different levels, representing the order of appearance and relation- 

 ships of the mesenteries and *epta. In fig. 86 two metacnemic pairs (A, A) have appeared within the 

 dorsal exocieles. For fuller description see pp. 456 and 499. X 100. 

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