Books with author The Carnegie Institution

This book an EXACT reproduction of the original book published before 1923. This IS NOT an OCR?d book with strange characters, introduced typographical errors, and jumbled words. This book may have occasional imperfections such as missing or blurred pages, poor pictures, errant marks, etc. that were either part of the original artifact, or were introduced by the scanning process. We believe this work is culturally important, and despite the imperfections, have elected to bring it back into print as part of our continuing commitment to the preservation of printed works worldwide. We appreciate your understanding of the imperfections in the preservation process, and hope you enjoy this valuable book.

This is a pre-1923 historical reproduction that was curated for quality. Quality assurance was conducted on each of these books in an attempt to remove books with imperfections introduced by the digitization process. Though we have made best efforts - the books may have occasional errors that do not impede the reading experience. We believe this work is culturally important and have elected to bring the book back into print as part of our continuing commitment to the preservation of printed works worldwide.

This is a pre-1923 historical reproduction that was curated for quality. Quality assurance was conducted on each of these books in an attempt to remove books with imperfections introduced by the digitization process. Though we have made best efforts - the books may have occasional errors that do not impede the reading experience. We believe this work is culturally important and have elected to bring the book back into print as part of our continuing commitment to the preservation of printed works worldwide.

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1908 Excerpt: ...as shown in textfigure 1. In this genus the pharynx extends inward at least as far as the circular constriction, about one-third the length of the entire body (plate 1, fig. 2a). The walls of the pharynx are thrown into longitudinal plications, which become continuous with the mesenterial filaments of the macrosepta (plate 4), as in Zoanthella. The septa are relatively larger than in Zoanthella, and this is especially true of the microsepta, but Van Beneden holds that their arrangement and order of appearance are the same in the two genera, i. e., the dorsal direct ives are imperfect, the ventral are perfect, and of the two remaining pairs on each side the dorsal memher of each pair is perfect and the ventral one imperfect, while the order of appearance is, for the macrosepta, 1, lateral; 2, dorsal; 3, ventral; and for the microsepta, 4, dorso-lateral; 5, ventro-lateral; 6, dorsal directives. McMurrich agrees with Van Beneden that the arrangement of the septa of Zoanthina is characteristic of the Zoanthca, but he suggests that the sequence observed by Van Beneden is really due to the retardation of the development of the dorsal directives, which should, according to his view, stand fourth in the order of development. In all my sections of Zoanthina the dorsal directives are smaller than the other microsepta (text-fig. 1 and figs. 24, 25), and if the order of appearance is to be judged by the relative sizes of the septa, the dorsal directives are the last to appear of these 6 pairs. Therefore, my observations as to the sequence of the septa in Zoanthina agree with the conclusions of Van Beneden. The individual septa are not triangular in cross-section, as in Zoanthella; on the contrary they are nearly as wide at the base as at the free border, and they all s...