230 TWENTV-THIRD REPORT OX THE StATE CaBIXET. 



preserve the character very satisfactorily while, in the other, C. magna, 

 although indistinct from excess of sililication, it is evident that con- 

 necting pores have existed. On the tilling of the cell-tubes of C. fihrosa 

 (Yol, II, Pal. N. Y., PI. 38, fig. 4 a), there exists small projections 

 which, evidently, remain from the decomposition of the substance of 

 the coralline body. In the case of C. dichotoma Hall, from Devonian 

 rocks at jS^ew Hamburg, Illinois, weathered specimens show satisfac- 

 torily the existence of similar pores of rather lai*ge size. 



One species here referred to this genus (6\ palTnata) differs from the 

 characteristic forms in another respect, not having the cell-tubes 

 "radiating equally on all sides from the axis;" it being composed 

 of broad, irregular, frondose branches, and dift'ering from the true 

 Cladopora, in the same manner that the palmate forms of Madre- 

 PORA do from the round, branched forms of that genus. But as, in 

 all other respects, it agrees with the generic characters given, and has, 

 also, the communicating pores between the dilferent tubes, there can 

 be no hesitation to include it with the other forms of Cladopora. 



Cladopora prolifica n. sj). 



Plate 10, flg. 3. 



Coral growing in loose masses of slender, branching stems, of about 

 three-sixteenths of an inch in diameter, with distinct bifurcations, form- 

 ing angles of about 35° at a short distance above their fork. Cells 

 proportionally rather large, longer than wide, often slightly sinuate on 

 the lower side, and spreading above to the base of the next cell in 

 advance ; margins of the cells thin and sharp ; communicating pores 

 large and distant. 



This species is somewhat smaller than C dichotoma Hall, with 

 much thinner, intercellular spaces, and somewhat smaller cells. It 

 occurs in large masses, eight or more inches in diameter, composed of 

 rather distant branches which appear to coalesce occasionally. 



Formation and locality. In limestones of the age of the Upper 

 Helderberg of New York, at Waterloo, Iowa. Presented by Mr. O. 

 H. St. John. 



Cladopora magna n. sj>. 



Plate 10, flgs. 3, 4. 



Coral growing in strong, ramose branches, of from one-fourth to five- 

 eighths of an inch in diameter, with frequent bifurcations which form 

 angles of variable extent. Cells of moderate size, closely arranged, 

 slightly transverse and spreading above, with salient margins, varying 

 from a sixteenth to a twelfth of an inch in transverse diameter. 



This is a very robust form and attains a much larger size than any 

 previously described species. The general aspect of the branches is 

 much like that of Striatopora, but the form of cell is ditierent, and 

 they have no apertural strioe and no transverse septa, so tar as ascer- 

 tained. 



