134 THE BERMUDA ISLANDS. 



to show that the actiniati fauna of the Bermudas has been de- 

 rived from that of the West Indies. 



Explanation of Plates. 

 Jc^basal canal. ew.=endoderm. 



c.=column wall. /r. fronds, 



cm. =circular muscles. m.=margin. 



CM.=cuticle. p.==tentaculifortn fronds, 



d.^^disc. sp.=sphincter. 



di.=digestive region of mesen- 

 terial filament. sp\=lower sphincter. 

 j5J;.=Ectoderm. f.=tentacle. 



Plate 10. 



1. Transverse section through the middle region of the 

 sphincter of Aiptasia sp. (?) X 350. 



2. Longitudinal section through the upper half of the column 

 wall of Aiptasia sp. (?) X 40. 



3. Transverse section through the outer edge of the longitu- 

 dinal mesenterial muscles of a specimen of Condylactis passi- 

 flora from the Bermudas. X 42. 



4. Longitudinal section through the margin and adjacent 

 parts of Diplactis Bermudmsis. X 24. 



5. Longitudinal section through the margin and adjacent 

 parts of Ouladis fasciculata. X 21. 



6. Transverse section through the longitudinal mesenterial 

 muscles below the stomatodseum in Diplactis Bermudmsis. 

 X40. 



Plate 11. 



1. Perfect mesentery of Diplactis Bermudensis. Natural size. 



2. Portion of transverse section of sphincter of Diplactis 

 Bermudmsis. X 100. 



3. Transverse section of mesenterial filament of Zoanthus 

 7?os-mannMS just below the stomatodteum. X 120. 



4. Transverse section of perfect mesentery of Zoantlms flos- 

 marinus slightly below the stomatoda;>um. X 50. 



