. Annual report . 1 Wiman has in a later paper [1900, ] pointed out in defense of his view thatthe nematocalyces occur in pairs, while hut one gonangium is found associated with atheca, and further, that the nematophores, as defensive polyps, have as a rule an exposedposition while the organs considered by him as gonangia are found in protected GRAPTOLITES OF NEW YORK, PART 1 ~M.\ While our material, which is preserved in clay slates, seems unfit toallow any such method of investigation as Wiman employed, it will atleast sometimes permit the observation of the composite nature
. Annual report . 1 Wiman has in a later paper [1900, ] pointed out in defense of his view thatthe nematocalyces occur in pairs, while hut one gonangium is found associated with atheca, and further, that the nematophores, as defensive polyps, have as a rule an exposedposition while the organs considered by him as gonangia are found in protected GRAPTOLITES OF NEW YORK, PART 1 ~M.\ While our material, which is preserved in clay slates, seems unfit toallow any such method of investigation as Wiman employed, it will atleast sometimes permit the observation of the composite nature of thebranches, as in the specimen reproduced in text figure 28. In this, someparts have been slightly infiltrated with pyrite, which has brought outplastically the narrow tubes, running alongside of the thecae and presum-ably representing the gonangia and budding individuals. The absenceof any axis is also distinctly shownin this specimen. The numerouslarge pores appearing on the sur-face of certain compressed branches HgjB mctyonema rarum Wiman. Fras, -, -, n i ment of a branch etched out of flint. Shows the are apparently tile apertures OI the thecae and the apertures of the gonangia. xll. *? x x (Copy from Wiman) thecae. The question of the mode of life of the Dictyonemas has been mootedrepeatedly. Hall gave in Palaeontology of New York, volume 2
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