ANATOMY OP THE MADREPORARIAN CORAIi FQNGIA. 323 



DESCRIPTION OF PLATES XXIII, XXIV, & XXV. 



Illustrating Mr. Gilbert C. Bourne^s Paper on " The Anatomy 

 of the Madreporarian Coral Fungia/' 



Fig. 1. Ad naturam. — General view of Fungia dentata, showing the ar- 

 rangement of the tentacles and their relation to the septa. 



Fig. 2. — Diagram in illustration to Fig. 1. m. Mouth, t. Tentacles. 

 1, 2, 3, 4, 5, 6. Septa (or tentacles) of the first, second, third order, &c. 

 Primary septa coloured red, secondary blue, tertiary green, quaternary yellow, 

 quinary, &c., black. 



Figs. 3—8. — Diagrammatic, from Stutchbury, Semper, and Moseley. 

 Fig. 3 is a young nurse-stock of Fungia immediately after fixation. 



p. Peristome, th. Theca. b. Base. 

 Fig. 4. The same, in which the 'peristome has commenced to widen out 



and assume its characteristic form. 

 Fig. 5. Nurse-stock of Fungia; an absorption of calcareous matter has 

 taken place along the line/, where the young Fungia will separate from 

 the nurse-stock. 

 Fig. 6. Young Fungia shortly after separation from the nurse-stock. 



The peristome has grown greatly in excess of the theca. 

 Fig. 7. The same more advanced, showing the increasing size of the 



peristome. 

 Fig. 8. The adult Fungia. 

 Fig. 9. — Diagram showing a pair of mesenteries and their relation to the 

 investing tissues of the corallum. The mesentery to the left is seen to be 

 divided by a synapticulum into a central and a peripheral portion, ec. Ecto- 

 derm, m. Mesogloea of the body wall. ed. Endoderm of the body wall. 

 m'. Mesogloea of the mesenteries, m". Mesogloea of the skeletotrophic 

 tissues, ed'. Endoderm of the mesenteries, ed". Endoderm of the skeleto- 

 trophic tissues, ms. Muscles. ci/. Calycoblasts. cd. Nematocysts. m.f. 

 Mesenterial filaments. sb. a. Symbiotic algse. spi. Perforation through 

 which a synapticulum passes. 



Fig. 10. Ad naturam.— A mesentery of Fungia dentata. ac. Acontia. 

 V. m. s. Longitudinal muscle-fibres, the remainder of the lettering as before. 

 The shaded part represents that part of the mesentery which is formed of 

 mesoderm and its overlying muscular fibres. The dotted lines show the 

 tubes (parts of the ccelenteron) bounded by endoderm of the skeletotrophic 

 investment which run down between the synapticula, to the mesogloea of 

 which thickened prolongations of the mesogloea of the mesenteries are attached, 

 as shown in x. 



