Favosites polymorpha. _Lign. 86. Lign. 88, fig. 3._--Polyparium stony, polymorphous, solid internally, compact, composed of a congeries of diverging or ascending parallel, contiguous, prismatic tubes, covered by pores, divided by lamellæ, and communicating by lateral foramina. The corals of this extinct genus abounded in the Silurian and Devonian seas; the remains occur with those of other fossil zoophytes of that epoch in great numbers, both in Europe and North America. I have many beautiful examples from the Silurian rocks of the Ohio and Niagara, by favour of Dr. Owen, of New Harmony, and Dr. Yandell, of Louisville, in which the cells are filled up with calcareous spar. The varied markings on many of the Babbicombe marbles, and Torquay pebbles, are derived from the enclosed Favosites (_Wond._ p. 643). Another species (_Favosites Gothlandica_) occurs in masses of a subconical shape, and is common in some of the Silurian limestones. A fragment, to show the structure, is figured _Lign. 88, fig. 3_. [Sidenote: CATENIPORA. SYRINGOPORA.] Catenipora (_Wond._ p. 644, _fig._ 3).--Polyparium hemispherical, composed of vertical anastomosing lamellæ; cells tubular, oval, terminal, united laterally. The oval form of the cells when united laterally, and the flexuous disposition of the lamellæ, give rise in transverse sections to elegant catenated markings, from which appearance the fossil has received the name of _chain-coral_.[240] The species figured (_C. escharoides_) in _Wond._ is common in the Silurian limestones, and sometimes forms hemispherical masses more than a foot in diameter. The chain-coral is extensively distributed through the Silurian rocks of the United States. Coloured figures of this exquisitely beautiful coral are given in _Pict. Atlas_, pl. XXXV. [240] Org. Rem. vol. ii. pl. iii. figs. 4, 5, 6. Syringopora ramulosa. _Lign. 88, fig. 2._ (_Wond._ p. 641.) These corals bear a general resemblance to the Organ-pipe Coral of Australia. The polypidom is composed of long, cylindrical, vertical tubes, distant from each other, and connected by transverse tubular processes; the cells are deep and radiated by numerous lamellæ. The external aspect of these fossils is that of a cluster of cylindrical pipes, more or less parallel, connected by short transverse branches. They are the _Tubiporites_ of Mr. Parkinson, who has given admirable figures of several specimens.[241] In these fossil corals that excellent observer first detected the animal membrane. A slab of marble, whose markings are produced by the section of the inclosed tubes of a Syringopora, is represented, _Wond._ p. 644, _fig._ 2. The Mountain limestones of Derbyshire, and of Clifton, on the banks of the Avon, contain figured marbles of this kind, which are manufactured into vases, tables, &c. The genus is extinct. [241] Pict. Atlas, pl. xxxv. _fig._ 1. Syringopora geniculata, Pict. Atlas, pl. xxxiv.