ECHINODERMS. 



1. EcMnanthus rosaceus. Upper side. One-third natural size, covered 

 with short purple or olive spines vphen alive. 



2. Oreaster gigas. It is sometimes more than a foot in diameter. Covered 

 with hard knobs connected by low ridges. Bright red or orange, when alive. 



3. 4. Cidaris tribuloides. 4. A small specimen in its natural state. 

 3. The same after the spines have been removed, showing the knobs to which 

 they are attached. One-half natural size. 



5. Biaderna setosuin. A "Sea Egg" with very long spines. Black, or 

 banded with black and yellow. When the spines are removed it resembles 

 fig. 3, but the knobs are smaller and more numerous. One-half natural size. 



