49 
of the parent, not simultaneously, but in succession, each from its own side 
and meeting in the middle. The most peculiar feature of P . tubulatum is the 
occurrence of exothecal structures in the form of “ numerous curious little 
scales ” on the pseudocoste or rugae of the simple forms, arranged longi- 
tudinally, and “ which generally fall off,” each pair of rugae bearing two rows 
of scales. These are described in detail by Dr. Lindstrom, and are compared 
to the opercular valves of Arceopoma prismatic a ; the scales in question are 
not found on the compound corallums of P. tubulatum. The whole structure 
of the latter, omitting these exothecal scales from consideration, is precisely 
that of Tri/plasma. 
1882. — The structure of the coral already referred to as Cyathopkyl- 
lum (?) Loveni , or, as it is sometimes spoken of by Authors, Pholidophyllum 
Loveni, has been very fully treated of by Mr. G. von Koch. 1 He confirmed 
the remarks of Edwards and Haime on the presence of spiniferous septal 
lamelloe. The tabulae, and other points of structure, including the gemmation, 
are strictly those of Tryplasma as revealed in Australian specimens. Koch’s 
figures of the budding are very valuable, as they illustrate the gradual 
appearance of the young corallites from the earliest stage in one and the 
self-same parent eorallite. In this series of five figures we trace the 
appearance of four buds, each one commencing as a small inwardly convex 
continuation of the mother wall, gradually enlarging and extending inwards 
until the whole of the parent calice is filled up. 2 Even more interesting, 
however, is the extension inwards of the maternal septal spines within the 
boundary of a bud to become the peripheral septal lamina) and spines of the 
latter, whilst those springing from the inner wall of the hud are a new 
creation ; these buds are bilaterally symmetrical. A glance at the gemmation 
of our T. princeps, T. liliiformis, &c., will at once indicate how close a 
connection there is between their mode of increase and that of P. Loveni. 
1883. — In this year Dr. Lindstrom, in a most useful paper — “ Index 
to the Generic Names anolied to the Corals of the Palaeozoic Formations,” — 
A JL J 
again placed Tryplasma as a synonym of Pholidophyllum . :i 
1883. — In the volume of Richthofen’s great work on China, devoted to 
Paleontology, the same eminent describer of Paleozoic Corals described 
and figured three species of Amplexus of Upper Silurian age, viz., A. viduus, 
1 Koch — Palaeontographica, XXVIII, 6 Lief, 1882, pp. 216-210. 
s Koch — Hid. t. 43 (1), f. 18-22. 
* Lindstrom — Bihang K. Sv. Vet.-Akad. Handl., 1883, VIII, No. 9, p. 12, 
