172 



CLASS-BOOK OF ZOOLOGY. 



2d Order. — Corals. 



5G. The Eatable Sea Hedge-hog. | 58. The Red Sea-star. 

 57. " Orbicular Sea Hedge-hog. | 59. " Northern Sea-star. 



5th Order. — Long-bodied Worms. 



References on the Natural History of Worms. 



J. B. Lamarick, Histoire naturelle des Animaux sans Vertebres... • 1816 



T. F. Blumenbach's Handbuch der Naturgeschichte 1825 



L. Oken's Naturgeschichte fur alle Stande 1835 



Ehrenberg iiber Infusorien 1830 



