Abstract
The Quarterly Journal of Microscopical Science for August 1895 contains: On the variation of Haliclystus octoradiatus, by Edward T. Brown (plate 1). Some 154 specimens were examined, 120 of these were perfectly normal but 34 afforded either cases of congenital variation, or showed regeneration of organs after destruction or injury. Most of the abnormal forms are figured.—On the collar-cells of Heterocœla, by George Bidder (plate 2). Observations were made on Leucandra aspera, Sycon raphanus, S. compressum; this last was found best suited for examination under high powers during life, its collar-cells are among the largest, if not as large, as any known. The protoplasm of these cells is in life greenish, and they have nearly the form and relation to each other of full corn-sacks standing side by side in a granary. The living collar is invariably an almost perfect cylinder, very little constricted at its base. As to Sollas's membrane, the statements of Vosmaer and Pekelharing, which the author once thought erroneous, he now confirms, there is no normal union of the collars, the membrane is only to be met with in “paraffin sections.”—The metamorphosis of Echinoderms, by Henry Bury (plates 3-9). With the view of clearing up some of the differences in observation and opinion of the more recent observers of the metamorphosis of this group, the author has worked out as far as possible the metamorphic changes of at least one form of larva in each of the five classes of Echinoderms; for reasons given, the metamorphosis of Synapta is written in greater detail than that of the rest. As to the relation of the Echinodermata to the Enteropneusta, “there seems to be a chain of evidence of their connection, which though not indeed conclusive—that embryological evidence alone can never be—is at least as strong as that which binds together any two of the great subdivisions of the animal kingdom.”—A criticism of the cell-theory; being an answer to Mr. Sedgwick's article on the inadequacy of the cellular theory of development, by Gilbert C. Bourne. The article of Prof. Sedgwick here criticised appeared in the Q.J.M.S. for November 1894.
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Scientific Serials. Nature 53, 212–213 (1896). https://doi.org/10.1038/053212b0
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DOI: https://doi.org/10.1038/053212b0