. Corals and coral islands. Coral reefs and islands; Corals. CORALS AND CORAL MAKERS. 35. ORBICELLA CAVERNOSA. begin to exceed the width usual to the species, a new mouth opens, commencing a new polyp ; and thus the growth of the mass involves multiplication by buds. The small calicle near the centre of the figure is from one of the new interstitial buds. Species of Pontes also grow into hemispheres and rude hil- lock-like forms, through the same method of budding, and some of the masses in the tropi- cal Pacific have a diameter ot even twenty feet. Myriads ot living polyps are combined in a s
. Corals and coral islands. Coral reefs and islands; Corals. CORALS AND CORAL MAKERS. 35. ORBICELLA CAVERNOSA. begin to exceed the width usual to the species, a new mouth opens, commencing a new polyp ; and thus the growth of the mass involves multiplication by buds. The small calicle near the centre of the figure is from one of the new interstitial buds. Species of Pontes also grow into hemispheres and rude hil- lock-like forms, through the same method of budding, and some of the masses in the tropi- cal Pacific have a diameter ot even twenty feet. Myriads ot living polyps are combined in a single such mass, for each is but a fifteenth or a twentieth of an inch in diameter. Often there is a lateral growth of the polyp and thereby of the zoophyte without much upward growth; and spreading leaves are thus made, and bowl-like shapes. Where there is lateral budding, the leaves have generally an edge of young polyps from the new buds that are there opening, as in the Gemmipores, and some foliaceous Madrepores; where there is superior budding, and sometimes in the case of inferior, the new polyps appear some distance from the edge, the growing margin spreading on in advance of the buds that open in it, as in the Echinopores. Besides the method of budding explained in the above re- marks, there is also a kind of superior budding called sponta- neous Jission^ which consists in a spontaneous subdivision of a polyp, by which two are made out of one. In such cases the disk of the polyp has not a distinct limit of growth, as in the above, but tends to enlarge indefinitely; and when there is a beginning of an increase beyond the proper adult size, a new mouth opens in the disk, a short distance from the old one, and at the same time its edges extend downward and make a new stomach beneath it; finally tentacles are developed between the two mouths, and then each polyp separates with its part of D 2. Please note that these images are extracted from scanned page images that may hav
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