LUNUL. 



364 



liunulicardium ornatum {Pinnopsis ornatus). Hall, 



Keport on the Third or Western 

 ^"'*^' ^^'^ District of New York, 1843, page 



106^ /j^B^^^S^ y^licardium acutirostra (which 



lived with it in the same Portage 

 sandstone formation) that they 

 are often mistaken for each other ; 

 but this has more than 40 diverg- 

 ing ribs, and the other only 26 ; 

 and they are crossed by beauti- 

 fully arched striae. The general 

 shape of the two shells differs 



also. — Cashaqua creek, N. Y. — VIII f^ 



Lycopodiacese, called Olub Mosses, now living in tropical 



countries, explain a whole class of vegetable fossil forms found 

 in the roof shales of coal beds. See Collett's Indiana Report 

 for 1883, page 76, and his plate 16, figs. 1, 2, 3, stem and 

 branches of a living lycopod^ figs. 4, 4t», enlarged, of axilary 



