SECONDARY AND TERTIARY FORMATIONS OF NORTH AMERICA. 119 



LUNULITES, Lam. 1801. 



Colony conical, circular or approaching it ; fixed in the young state to a grain of 

 sand or other substance, free when mature. Cellules like the others of the Escharidce, 

 all on the superior surface, arranged in radiating lines from the centre ; interpolated 

 rays always commence by an abortive cellule. Under surface concave and marked 

 by radiating, irregular lines. 



L. sexangula, Lonsd., Quart. Jour. Geol. Soc. vol. 1, p. 531. 



" Obtusely conical ; cells hexagonal, in alternate rows, surface covered, raised near the distal extremity, 

 depressed in the centre, a hemipherical tubercle frequently at the proximal end ; mouth nearly central, 

 transverse, very narrow ; casts of interior of cells hexagonal, parallel to the convex and concave surfaces ; 

 concave surface casts of irregularly radiating punctured ridges and narrow furrows, the ridges traversed 

 more or less regularly by a row of tubercles ; interval between the convex and concave surfaces equal depth 

 of cells." 



" Locality, Wilmington," [N. C, Eocene.] 



We are not acquainted with the above species. No figure is given. 



L. distans, fig. 4. 



L. distans, Lonsd., Quart. Jour. Geol. Soc. vol. 1, p. 531, figs, o, 6, c ; id. d'Orb., 

 Prod. Pal. Strat. vol. 2, p. 397, No. 1182. 



Colony conical, sometimes flattened above, sometimes rounded ; covered with cel- 

 lules on the upper or convex surface in regularly radiating and in transverse lines. 

 New lines always commencing by an abortive cellule. Cellules subquadrate to pent- 

 agonal, in which case the odd angle is in front, overlapping the succeeding cellule ; 

 this form, sometimes modified to a regular curve anteriorly, is the common form. 

 The cellules are arranged, as stated above, in regular radiating lines, the longitudinal 

 rows being much more intimately connected with each other than they are laterally. 

 Between the cells laterally we find a row of pores, sometimes of an elongated fusiform 

 outline and sometimes rounded posteriorly, and constricted near the middle. "We 

 shall notice these more fully below. The mouth of the cellule is somewhat anterior 

 but not terminal ; placed at the lowest part of the surface ; round or subquadrate. 

 Surface carinate parallel with its anterior and lateral outlines, sloping outwardly to 

 the edge and inwardly towards the mouth, sometimes with an elevated portion, 

 bounded by two radiating depressions, posterior to the mouth. 



Casts of the interior of the cellules, on which Lonsdale founded the species, and 

 which are by far most common, are characterized by rather long, tapering, oblique 

 projections, showing the interior of the cellule and the cast of the outer walls ; ar- 

 ranged in regular radiating rows, and in transverse lines, with, generally, distinct 

 ridges between them. Sometimes they exhibit casts of the connecting pores between 

 adjoining cellules. The intermediate pores seen on the surface are not visible from 



the interior. Under surface, of which we have only seen casts, is marked by deep 



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