Report of U. S. National Museum, 1901 



Plate 64. 



THE TEGMEN. 



The Tegmen m its simplest form :s composed of 5 plates called 

 ored red*. There are nearly always present also atntulacrals (colored blue , covering the 

 food grooves or ambulacra that lead from the brachia to the mouth. In many Paleozoic 

 genera the ambulacra! plates are covered by the m:,ii:i.-mi Jo'mt plates .colored yellow,. 

 When the dorsal cup is enlarged by other plates than those of a simple crinoid the teg- 

 men also introduces supplementary plates known as mteramiulmrah [black). Finally the 

 tegmen may be in the form of a coriaceous skin, in which large numbers of thin calca- 

 reous ossicles are embedded. 



The mouth is nearly always covered by the deltoids or the dome plates while the 

 mus, which is closed by a a, vim fyramte, is often surrounded by, or raised on. small plates 

 colored brown . 



Crinoid Series— the Tegmen. 



