JFi)ssiI Corals i — Lower Silurian Roclis o/' Canada. liS 



^^^^_^^,5.,-.f»?ywt,,^^ Figure 2 will give an Idea 



.s^jS^"^^^ "^ti^Ni^^^. upon a small scale of a domc- 



^v/^^4 y!:^m^<^^L,-'"'^'^^^ shaped coral. This figure is 



.#^^f?^l %^^^ i:'-^- copied from Sillimau's Ameri- 



/%^'^i0$ -.'^~-y^>---W''0''?^^^^^ can Journal of Science, isew 



4%'^^''''^^^'^.^^^^^ Series, vol. 3, ]-rage 3. In that 



llilfe Sfh ^^^^5^^^^H volume of -the Journal there are 



^J^,l^ ^^^II ^^^^P several fine articles on Coralt-, 



"^=^^^^ 7^:^^^^ ^=^^^^^^^^^^^^^^^=- j)qj^^^ ^yjjo spent several years 

 Fig. 2, Astrm purpurea, (Dana.) ^^^^„ ^i^g (.^^,^^1 j^j^^^^g ^f ^j^^ 



Pacific and other seas, and whose magnificent work upon the Zoophytes* is 

 'Considered to be one of the best contributions ever made to any department 

 of Natural History, Mr. Dana says in one of the articles in question : — 

 '^ Many of the various shapes v/hich these zoophytes assume, are familiarly 

 linown. Madrepore shrubs and trees, and the sea-fan and other Gor- 

 gonias from the West and East Indies, are common in collections. — 

 The hemispheres of hrain-coral (Meandrina,) and also of star-cordl 

 (Astrcea,) are often met with. It is very generally supposed that these are 

 hy far the most frequent, if not the only shapes presented ; but, on the con- 

 trary, the varieties are extremely numerous, as we have already intimated. 

 Some species grow up in the form of large leaves rolled around one another 

 like an open cabbage, and cabhage-coral would be no inapt desiguation for 

 such species. Another foliated kind consists of leaves more crisped and of 

 more delicate texture, irregularly clustered ; — lettuce-coral wonld be a signi- 

 ficant name. Each leaf has a surface covered with polyp-flowers, and was 

 formed by the grov/th and secretion of these polyps. Clustered leaves of the 

 acanthus and oak, are at once called to mind by other species ; a sprouting 

 asparagus-bed by others. The mushroom is here imitated in very many of 

 its fantastic shapes, and other fungi, with mosses and lichens, add to the 

 variety. 



" Yases of Madrepores are common about the reefs of the Pacific. — 

 They stand on a cylindrical base, which is enveloped in floAvers when alive, 

 and consist of a network of branches and branchlets, spreading gracefully 

 from a centre, covered above with crowded sprigs of tinted polyps. The 

 \ii3es in the collections of tile Expedition, at Washington, will bear out this 

 description, although but the lifeless coral. 



" The domes of Astneas are of perfect symmetry, and often grow to a 

 diameter of ten or twelve feet without a blemish. The ruder hillocks of 

 Porites are sometimes twenty feet across. Besides these, we might describe 

 columns, Hercules' clubs, and various strange shapes which are like nothing 

 feut themselves. 



" It is an enquiry of much interest, how these various formB proceed 

 from the budding process. 



* Zoophyte, from fhe Greek, ("Zoon,^ an animal, and (^Phytoji,') a plant. — 

 T^e word is used with various limitations of meaning l>y different authors, hul 

 iieems to be synonymous with Polyp. 



