.PLATE XXIX. 



Clypeaster subdepressus. 



1. (Upper figure.) Abactinal part of test seen from the interior, to show the position of the 



ovaries and principal partition (p) between the anibiilacral and digestive cavities, 

 0, 0, o', o", o'", o'^; 0^, ovaries ; a, median ambulacral space? ; a,j, ambulacral furrows 

 of petals ; g, g, genital tubes leading to ovaries ; fi", pit leading to anal opening ; 

 IV, attachment of stone canal. 



2. (Lower figure.) Abactinal part of test removed, to show the trend of alimentary canal ; 



■m', entrance to oesophagus ; i", termination of cesophagus leading to digestive canal, 

 i'", i" ; i", point of flexure of canal to i, leading to anal opening, a" ; /ij), partition ; g, 

 genital tubes leading to ovaries ; i>, v, vessel along oesophagus and intestine ; j, lateral 

 half of pp-amid ; f, central line of contact ; /', median part ; /", basal portion ; r, 

 rotule. 



{Both Figs, natural size.) 



The Drawings are made from preparations by A. AGASSIZ and JAMES E. MILLS. 



I 



