375 



Lunarium — a more or less thickened portion of the posterior 

 wall of the cell in many Palaeozoic Bryozoa, which is 

 lnnateor curved to a shorter radius, and usually projects 

 above the plane of the cell aperture. 



Lunule — the depression in front of the beak of Pelecypod 

 shells. 



Macerate — softening and disintegrating by immersion in 



water. 

 Maculae — irregular, usually depressed, areas on the cellulif- 



erous face of a Bryozoan frond, which are free from cells. 



or otherwise differentiated. 

 Mesial — central . 

 MesoQ-lcea — the central, non-cellular laver in the bodv of 



Ccelenterates. 

 Meso-pores — irregular meshes, or cysts, on the intercellular 



spaces of certain Bryozoa. 

 Mesotheca—a median wall separating opposed cells in cer- 

 tain Bn^ozoan fronds. 

 Mold— Any impression of a fossil, in rock matrix, whether 



external or internal. 

 Moniliform — resembling a necklace or string of beads. 

 Monticules — elevated areas on the surface of certain coral and 



Bryozoan colonies, commonly carrying larger apertures. 

 Mucronate — produced into a long pointed extension. 

 Mural pores— the pores in the walls of the corallites of the 



Favositidse. 



Nacreo us— pearly; the nacreous layer of shells is the inner 



smooth pearly layer. 

 Nasute — projecting, nose-like. 

 Node— a knob; usually considered as ornamental. 

 Nodose — bearing nodes or tubercles. 



Obconical — inversely conical . 



Occipital— applied to the posterior part of the cephalon of 

 a Trilobite. 



