284 
The American Geologist. 
May, 1891 
GEXUS. 
FOUNDER. 
TYPE. 
GROWTH. 
(8 
i. 

£ 
a 

+■> 
£ 
(0 
i- 
a 
« 
a 
u. 
1 
CO 
CO 
25. 
26. 
Densiphyllum. 
Dybowski, 1873. 
D. THOMSOXI. 
Simple or fas- 
ciculate. 
Grewingkia. 
Dybowski, 1873. 
G. (llisiophyl- 
LUM.i BUCEROS, 
EICHW. 
Simple. 
27. 
Heterophrentis. 
Billing's, 187.",. 
H. SPATIOSA. 
Simple. 
28. 
LOPHOPHYLLUJI. 
Edwards and 
Haime, 1850. 
L. KOXIXCKI. 
Simple. 
29. 
Menophyllum. 
Edwards and 
Haime, 1850. 
M. TEXUIMARGIX- 
ATUM. 
Simple. 
30. 
Metriophyllum. 
Edwards and 
Haime, 1850. 
M. BOUCHARDI. 
Simple. 
31. 
Palgeophyllum. 
Billings, 1858. 
P. RUGOSUM. 
Fasciculate or 
aggregate. 
32. 
Pentaphyllum. 
DeKoninek,1872. 
Simple. 
33. 
Phryganophyllum. 
DeKoninck,1872. 
Simple. 
< 
34. 
Polydilasma. 
Hall, 1852. 
P. TURBINATUM. 
Simple. 
H 
Ul 
-1 
35. 
* Ptychophyllum. 
Edwards and 
Haime, 1850. 
P. STOKESI. 
Simple. 
X 
III 
36. 
Pycnophyllum. 
Dybowski. 
Simple or com 
pound. 
37. 
Pycnostylus. 
Whiteaves, 1884. 
P. GUELPHEXSIS. 
Aggregate. 
E 
lb 
38. 
** Siphouaxis. 
Dybowski, 1873. 
S. TUBIFERUS. 
Simple. 
39. 
Streptelasma. 
(Streptoplasma, 
Hall). 
Hall, 1847. 
S. EXPAXSUM. 
Simple. 
40. 
Zaphrentis. 
(Caninia, Mich.) 
Rafinesque and 
Clifford, 1820. 
z. (caninia) pat- 
ULA, 3IICH. 
Simple. 
(5 
k 

£ 
a 
o 
c 

a 
i 
< 
u. 
1 
ffl 
D 
CO 
41. 
Acanthophyllum. 
Dybowski, 1874. 
Simple. 
42. 
t ACERVULARIA. 
(Astraea, Lam., pars.' 
Schweigger,1820 
A. ROOIERI. 
Astrseiforai 
i »r fascicu- 
late. 
43. 
At KoPHYLLUM. 
Thompson and 
Nicholson, 1870. 
A. (('LISIOPHYL- 
lum) O N E I - 
O.KXSE, BILL. 
Simple. 
44. 
Aspidophyllum. 
Thompson, 1874. 
Simple. 
45. 
16 
Al'LACOPHYLL'JM. 
Edwards and 
Haime, 3 850. 
A. (CANINIA) SUL- 
CATUM, d'orb. 
Simple. 
Aulophyllum. 
Edwards and 
Haime, 1850. 
A. EDWARDSI, 
DUX. A X D 
THOMP. 
Simple. 
47. 
48. 
AXOPHYLLUM. 
Edwards and 
Haime. L850. 
A. EXPANSUM. 
Simple. 
Blothrophyllum. 
Billings, 1859. 
B. I) EC ORTICA. 
TUM. 
Simple or in 
c ae spi tose 
clusters. 
• Fungi a, (pars) Lam. : Fungites, (pars) Schloth. 
■• Lindstroni states that this genus was founded upon silicified and altered frag- 
ments of an indeterminate coral. 
