LONSDALE ON MIOCENE CORALS FROM N. AMERICA. 



503 



mules. In every case, however, the first additional cell had been 

 clearly derived from that in which the regular successive cell 

 did not occupy the whole of the distal termination, there being, 

 in both instances, the same want of a distinct transverse separating 

 line, while between the interpolated and the other pre-existing 

 rows, the regular longitudinal furrow was continued. No signs 

 of accessory foramina or of gemmuliferous (?) vesicles were noticed. 

 Locality. — Petersburg. 



6. LUNUL1TES DENTICULATA Conrad. 



Conical ; cells in alternate rows, oblong externally, interior conical, nearly ver- 

 tical to the two surfaces of the polypidom ; immature state, exterior of cell open 

 or denticulated on the margin, mature, covered ; mouth near distal extremity 

 semi-circular when imperfect, circular when perfect ; gemmuliferous (?) cham- 

 ber at distal end of cell, opening round ; concave surface irregular, furrowed, 

 minutely granulated, or punctured ; distance between the two surfaces variable. 



a. Lunulites denticulata, magnified four times in linear dimensions. 



b. Cells greatly enlarged to exhibit the denticulated edge of the immature 

 state, and the characters of the chambers between the cells. 



Lunulites denticulata Conrad. Silliman's Journal, Oct. 1841. 

 (Vol.41.). 



This minute Lunulite is believed to belong to the species de- 

 scribed, but not figured, by Mr. Conrad ; and for a knowledge of 

 the notice in Silliman's Journal, I am indebted to Mr. Lyell. So 

 far as the only specimen contained in the collection would permit 

 a comparison to be made, it resembled greatly a Lunulite found in 

 the crag of England, and possibly that identified, in the " Annals of 

 Natural History" for January, 1844 (p. 18.), with the recent 

 Lun. Owenii of the African coast (Gray's " Spicilegia Zoologica," 

 part i. p. 8. t. 3. f. 15. 1828.) ; but as the published notice of the 

 latter does not afford sufficient means for determining the amount 

 of agreement between the recent and fossil corals, it has been 

 deemed advisable to adopt Mr. Conrad's specific name. 



This Lunulite differed from the species described in the notice 

 on the eocene polyparians (posted,), in the important characters of 

 the cells being arranged alternately, in the total absence of inter- 



