THE EDWAKDSIA-STAGE OF LEBEUNIA. 



313 



1897. VON Koch, G. — "Eatwicklung von CaryopliyUla cyathus." 



Mitt. a. d. Zool. Stat, zu Neapel, 12 Bd., 4 Heft. 



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Journ. Inst. Jamaica, vol. ii. No. 5. 

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 Hist., vol. V. 

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1898. 



1898. 



EXPLANATION OF THE PLATES. 



Eeference figures and letters. 



The Roman numerals I. to IV. are throughout opposite the four pairs of 

 mssenteries, and also represent respectively the order in which they usually 

 appear in the development of the Zoantharia. 



I. I. Sulco -lateral pair. 

 II. II. Sulculo-lateral pair. 

 III. III. Sulear pair of directive mesenteries. 

 lY. IV. Sulcular pair of directive mesenteries. 



The letters a-h correspond with the mesenterial chambers: a, sulear 

 endocoele ; h, left sulco- lateral chamber ; c, left median lateral chamber ; d,, left 

 sulculo-lateral chamber = sulcular exocoele; e, sulcular endocoele; /, right 

 sulculo-lateral chamber = sulcular exoccele ; g, right median lateral chamber ; 

 h, right sulco lateral chamber. Both for the mesenteries and the chambers 

 the terminology here adopted must necessarily become slightly altered as other 

 mesenteries appear. 



arc.w., wall of archenteron. 

 cl.gl.c, clear gland-cells. 



coe.s., coelouiic space. 

 d.nem., developing nematocyst. 

 cct., ectoderm. 

 ect.f., floor of ectodermal invagi- 

 nation. 

 gr.gl.c, granular gland-cells. 

 l.nem., large nematocyst. 

 l.lay., limiting liiyer. 



mesfil., mesenterial filament. 

 mus.l., muscular layer. 

 iier.l., nerve-layer. 

 as., oesophagus. 

 or., oral aperture. 

 s.nem., small nematocyst. 



sp.L, supporting lamella. 

 sup.c, supporting cells. 

 vo.t., vacuolated tissue. 

 zoox., zooxanthella;. 



