. The British Tunicata; an unfinished monograph. Sea squirts; Tunicata. BRITISH TUXICATA. branes much farther downwards than usual. The collar of tentacular filaments at the base of the in- halant tube is very near to the anterior margin of the v . O branchial sac; and there are fifteen or sixteen rather short filaments, with two or three minute ones between them. But what is most peculiar in this species is the deficiency of the branchial tubercle or any trace of it; we have examined three specimens and in not one of them could we find this enigmatical organ so constant in the Tunicata. The b
. The British Tunicata; an unfinished monograph. Sea squirts; Tunicata. BRITISH TUXICATA. branes much farther downwards than usual. The collar of tentacular filaments at the base of the in- halant tube is very near to the anterior margin of the v . O branchial sac; and there are fifteen or sixteen rather short filaments, with two or three minute ones between them. But what is most peculiar in this species is the deficiency of the branchial tubercle or any trace of it; we have examined three specimens and in not one of them could we find this enigmatical organ so constant in the Tunicata. The branchial membrane (fig. 13) is rather stout and is minutely plicated longitudinally ; the primary —. - - ' {\* ^ "* ffli FIG. 13. — Part of the branchial sac of Ascidla mamillata. Highly magnified. vessels are numerous and fine, Avith a few larger ones interspersed. The longitudinal bars are also numerous and less robust than the primary vessels with which they form square meshes ; there is a large conical papilla with the apex rounded, at each intersection, and as the meshes are small the papillae have a rather crowded appearance, especially as there is a small papilla on the longitudinal bars, between each pair of large papillae, and the membrane in connection with the latter is short. The meshes or stomata of the secondary vessels are of the usual rectilinear form, but are less elongated than in many species. The reproductive organs are confined to the right side of the body. The testicular caeca are spread over. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Alder, Joshua, 1792-1867; Hancock, Albany, 1806-1873; Hopkinson, John, 1844-1919; Norman, Alfred Merle, 1831-1918; Embleton, Dennis, 1810-1900. London, Printed for the Ray society
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Keywords: ., bookcentury1900, bookdecade1900, bookpubli, booksubjectseasquirts
