294 
The American Geologist. 
May, 1891 
MISCELLANEOUS. 
NEAREST RELATIVES. 
49. 
The tabula? are quite simple and may be remote 
or crowded. May extend nearly to wall. 
1. Amplexus. 
2. Cyathophyllum. 
60. 
The central area is occupied with a reticulate eel' 
lular tissue. 
CentroceHulosum. 
51. 
The internal wall is stated to be well marked. Out- 
er wall is wanting. 
Lonsdaleia. 
52. 
The central boss is formed by the conical tabulae 
and a few independent vertical lamella*, straight 
or spirally twisted. 
* Rhodophyllum. 
5a. 
Side faces of the septa are carinated as in Helio- 
phyllum and some species of Acervularia. 
1. Diphyphyllum. 
2. Heliophyllum. 
54. 
The septa may fall short of center, or in some spe- 
cies may be quite twisted. 
Heliophyllum. 
55. 
Columella is spongiose and contains some vertical, 
radiating, thin, discontinuous, more or less nu- 
merous, lamellae. 
Aulophyllum. 
56. 
The central area is composed of thin, irregular' 
wavy, discontinuous, eolumellarian plates- 
Centrophyllum. 
57. 
Central area is bisected by a median lamella, one 
extremity of which is directed towards the fovea. 
Aspiclophyllum. 
58. 
"Near the epitheca there exists a peculiar kind of 
intraseptal structure, consisting of narrow twist- 
ed strings of whitish color." 
Clisiophyllum. 
59. 
Secondary wall generally marginal and formed 
by inner faces of the vesicles. Corallites fre- 
quently connected by mural expansions. 
1. Craspedophyllum. 
2. Cyathophyllum. 
CO. 
External wall rudimentary, without epitheca; in- 
ner is sometimes double. Between the two 
structure is nearly entirely vesicular. 
Acervularia. 
61. 
The fovea is replaced by a strong principal septum 
which extends beyond the center. 
Aulacophyllum. 
62. 
Side faces of septa are supplied with carina?, ex- 
tending in a curve from the wall towards center. 
Convex upward. 
1. Craspedophyllum. 
2. Cyathophyllum. 
63. 
Septa form three complete cycla and four well 
characterized systems. Four primaries give a 
conical appearance to calyx. 
Stauria. 
64. 
Tabulate area may be more or less extended. 
When fovea is present it contains a single short 
septum. 
1. Axophyllum. 
2. Lonsdaleia. 
65. 
An internal wall, similar in character to that seen 
in Diphyphyllum, is sometimes indicated near 
the outer. 
1. Diphyphyllum. 
2. Koninckophylluni. 
66. 
A distinct inner wall is sometimes present be- 
tween the vesicular and tabulate area. Colu- 
mella is vesicular. 
1. Chonaxis. 
2. Lithostrotion. 
67. 
Septa are formed by superposed, sharp, inwardly 
directed folds of the continuous cell cups. Kad- 
iciform processes. 
Ptychophyllum. 
68. 
The septa in neighboring corallites are more or 
less confluent. 
Phillipsastrsea. 
69. 
Septa are conflueiit in neighboring corallites, 
sometimes carinated strongly. An inner wall is 
sometimes indicated. 
Pachyphylluin. 
70. 
Costa* are arranged in pairs. Simple specimens 
show a row of rhombic scales on each half of a 
longitudinal plication. 
71. 
Calicinal boss is low. rounded and traversed by 
the few spirally twisted ridges. Has no median 
crest. 
Clisiophyllum. 
72. 
Septa seem to merely striate the surface of the 
vesicles in the outer zone. 
1. Endophyllum. 
2. Lonsdaleia. 
*The genera Diburwphyllum. Aspidophyllum, Rhodophyllum, Cymateophyl- 
lum, Centrophyllum. ERstiophytlum and Albert in are very closely related to 
Clisiophyllum, and may be separated from it and from one another only by closest 
attention to the details of the central area. 
