266 



CEYLON PEARL OYSTER REPORT. 



EXPLANATION OF PLATES. 



LIST OF REFERENCE LETTERS. 



mull./:, amoeboid cell in mesoglcea. 



tiji.r., aperture of canal. 



mi., contracted autozooid. 



b.rn., battery of neraatocysts. 



c.///./., capitular marginal lobe. . 



r.ii ii., expanded autozooid. 



e.r., coelenteric cavity. 



cap., capitnlum. 



rap.mar., capitular margin. 



el., clubs. 



rul.ewl., columnar endodcrm. 



<.'., ciliated vessel. 



(Liii.f., dorsal mesenterial filament. 



i-ct., ectoderm. 



etui., endoderm. 



fwl.b.w., endoderm body-wall. 



I'nd.can., endodermal canals. 



</.?'., germinal vesicle. 



in.ui.xp., inter-mesenterial space. 



/.///./., lateral mesenterial filament. 



/. lobe. 



'/., mesentery. 



in.ap., mouth aperture. 



iiuti-Jnb., marginal lobe of capitulum. 



ing., mesoglcea. 



mg.li.il'., mesogloea body-wall. 



my.e.., mesogloeal cells. 



mg.d., dense layer of mesoglrea surrounding 



siphonozooids. 

 mil-., nucleus. 

 or., ovum. 

 s., stomodseum. 

 xi., siphonozooid. 

 sp., spicule. 



sp.h., hole left by spicule after decalcification. 

 $t., st;ilk. 

 ti'itl., tentacle. 



tr.x.e., transverse superficial canal. 

 /(/., tn)>ercle-like zooul on the stalk. 

 r.//(., ventral mesentery. 

 <.///./., ventral mesenterial filament. 

 IJMU., young autozooid. 

 yl,:, yolk of ovum. 

 so., ~j'., zoochlorellse. 



