APPENDIX A. (LONSDALE ON CORALS.) 
613 
The distinctive characters of one of these proposed groups or sub -genera were originally noticed 
in Russian specimens from the river Kakva and Petropavlofsk, and more recently under a differential 
form in a fine Gothland coral, contained in Mr. Murchison’s cabinet, and believed to he the Cyathophyllum 
articulatum of M. Hisinger (Letlima Suecica, p. 102. tab. 29. fig. 4). The peculiarities consist, — first, 
in the lamellae of the outer area being pierced, from the inner surface of the wall, through their whole 
breadth by well-defined, relatively large foramina, terminating on the inner edge in a distinct row of 
short tubuli ; and, secondly, in the total absence of interstitial vesicular laminae at every period of 
growth. 
For this sub-genus the name of Tryplasma is provisionally suggested, founded on the foraminated 
lamella; (rpvira, foramen ; e\atrpos, lamina). 
The Russian specimens were all imperfect fragments, hut that from the river Kakva was considered in 
a state to be so far compared with the Gothland coral, as to permit differential characters to be satisfac- 
torily ascertained. A mere comparison of the figures accompanying the following notice (PI. A. fig. 7), 
with that given by M. Hisinger, might alone lead to the inference of the two fossils being specifically 
distinct 1 ; but, independent of the great relative size and isolated nature of the one, and the slender form 
as well as dense grouping of the other, variations exist in the shape and arrangement of the foramina, and 
the characters of the lamellae. The gemmuliferous mode of reproduction carefully given in M. Hisinger’s 
figure, was also fully shown in the Gothland specimen, the offsets springing chiefly from the side of the 
parent stem, hut, possibly, in some instances from within the area of a once terminal cup. The nature 
of the Russian fragments prevented the detection of any analogous process. 
Cyathophyllum Sub-genus Tryplasma. 
Cyath. Tryplasma ccquabilis, sp. n. 
Cylindrical ; central area, transverse diaphragms broad, prolonged partly between the lamella ; outer area 
narrow, lamellae numerous, alternately broad and very narrow, foramina round ; outer wall thin. (PI. A. 
fig. 7.) 
This notice of specific characters, as well as the following memoranda, must he regarded as only in- 
dicative of the leading peculiarities of the fossil. 
The extent and dimension of the specimen from the river Kakva are given in figures 7, 7 a, Plate A; 
and though the fragment was so weathered as to exhibit perfectly no one surface, yet the oblique direction 
of the sections greatly facilitated the examination of the foramina. The diaphragms in their transverse 
range exhibited no distinctive characters, but beyond the central area, they were simply continued between 
and, possibly, through the lamella’, to the outer wall ; and therefore presented at the boundary of the 
lamclliferous zone, a marked difference from the complicated blendings in Cyathophyllum turbinatum. 
The lamellae issued boldly from the wall (fig. 7 a) exhibiting their full thickness in contact with it, but 
the extension of even the broader was limited. In the oblique vertical section (fig. 7), their range was 
indicated near the bottom by parallel rows of circles, alternately larger and smaller, the internal areas 
being more or less distinct, according, apparently, to the degree of blending between the decomposed coral 
and the infiltered lime. The rows were divided by bands of fine, slightly waved lines. Close to the left 
of the section the foramina were again shown, either in an analogous condition, or as distinct dark pores 
in a white crust. To the right of these rows, as well as lower down, and near the opposite boundary, 
were other series of circles with relatively broad, vertical intervals. Where the successive circles were not 
connected by any white or pale brown substance, they were believed to represent the tubular extensions on 
1 See also the figures of Tryp. ( Cyathophyllum, ) articulata, PL A. fig. 8, and the description of the Plate. 
4 K 
