. Report on the scientific results of the voyage of Challenger during the years 1873-76 : under the command of Captain George S. Nares, , and Captain Frank Turle Thomson, . have developed additional septa so as to appear as four majorchambers ; in these, however, pali are wanting opposite the so-called tertiary septa. Twoof their septa which have taken upon themselves, by the subdivision, the rank of primaryor secondary septa, have nevertheless opposite them still each a palus. As the coralwidens in growth, and these new septa of first order assume their full dimensions,
. Report on the scientific results of the voyage of Challenger during the years 1873-76 : under the command of Captain George S. Nares, , and Captain Frank Turle Thomson, . have developed additional septa so as to appear as four majorchambers ; in these, however, pali are wanting opposite the so-called tertiary septa. Twoof their septa which have taken upon themselves, by the subdivision, the rank of primaryor secondary septa, have nevertheless opposite them still each a palus. As the coralwidens in growth, and these new septa of first order assume their full dimensions, nodoubt their pali become lost to view, and partly fused with the columella mass, partlyincorporated in the growing septa. Two new pali must be developed in front of thetwo new tertiary septa to make up the fourteen, and in the young specimen now underconsideration a trace of one such new palus has commenced to grow in front of one ofthe four septa. The accompanying diagram will explain the mode of multiplication ofthe chambers and septa. The major septa are marked a, those of secondary size or thetertiary b, the new major and tertiary septa a and b respectively, the pali jj>, and the. a Diagram showing the mode of development of new septa and pali in Caryophyllia communis. new palus p. The new chambers develop in this coral in the same manner thereforeas in Flabdlum irregulare as described by Semper,1 that is to say, the additions to thesepta take place in the chambers at the ends of the longer axis of the calicle. It wouldseem probable that in some instances a pair of extra-major chambers develop, as in theyoung specimen first described, only at one end of the oval calicle ; hence are derivedthe specimens with fourteen pali. In other instances, probably, a pair of additional 1 C. Semper, Ueber Generationsweehsel bei Stemkorallen und iiber das M. Edwards sche Wachsthumsgesetz derPolypen. Zeitsch. fur Wiss. Zool., Ed. xxii., 1872, s. 243. REPORT ON CORALS—DEEP-SEA MADREPO
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectscienti, bookyear1881
