28 Prof. P. M. Duncan on the 



retain a considerable development as far as the columella. 

 The septal number appears to be incomplete five cycles. 



Costai variable in thickness, some large, may be alternately 

 large and small or subequal, never very prominent, close, 

 wavy, and more numerous than the septa, occasionally 

 uniting. Epitheca covering the costge and interspaces. 

 Synapticulas distinct, large between the costas, with a broad 

 attachment to the laminas, and a conical top ; numerous and 

 small between the septa. 



Height 16"5 millim., breadth of calice 11'5 millim., breadth 

 of stem 11 millim., breadth of the upper expansion 13 millim. 



Loc. Red Chalk, east of England. 



All the Podoserida3 appear to obtain their septal develop- 

 ment soon, and when very short the coralla have usually a 

 high septal number. 



This evident truth rather led to the belief that a very short 

 but broad form might be the young of Podoseris elongata^ 

 Dune. (Pal. Soc. 1869, Monogr. Brit. Foss. Corals, 2nd ser. 

 pt. ii. p. 26), or even of Podoseris Jessoni; but it appears 

 that the short form must be credited with five complete cycles 

 of septa. 



Podoseris brevis, sp. nov. (PI. V. figs. 7 and 8.) 



Corallum attached by a broad base, very low, subcylin- 

 drical. The calice is widely open, shallow, and slightly 

 narrower than the base. The septa stout, enlarging here and 

 there, long, uniting in groups, so that a few only (seven or 

 eight) reach the axial space, moderately close, lowly arched 

 above, and with rounded papilla3 on their free edge, or rudi- 

 mentary and placed between pairs of larger septa, and rarely 

 long enough to unite with one of the longer septa. Five 

 cycles. 



Columella formed by the septal ends. Costas short, usually 

 alternately large and small or subequal, covered with epitheca 5 

 bifurcation of the costoj rare. 



Breadth of the attached base lO'o millim., breadth of calice 

 9'5 millim., height o-3*5 millim. 



Loc. lied Chalk, east of England. 



Podoseris mamilli/ormis, Dune. (PI. V. fig. 9.) 



Podoseris ma?nmUiformis, Dune. 1869, Pal. Soc, Monogr. Brit. Foss. 

 Corals, 2nd ser. pt. ii. no. 1, p. 25. 



This species was the type of the genus and was described 

 from a considerable number of specimens, all of which were 



