. Annual report . es,that we infer that these genera may have been attached to the seabottom or to some objects during their growth. Nicholson [1872, the presence of the root; Brogger [1882, ] reports that hefound specimens of D. flabelliforme with siculae, the free endof which is pointed, and that that species certainly was notattached, which in all probability may be right for the genus ingeneral. 594 NEW YORK STATE MUSEUM Matthew, who had a large collection of D. flabelli forme fromthe St John basin for investigation, considered it as having had a floatingmode of existence
. Annual report . es,that we infer that these genera may have been attached to the seabottom or to some objects during their growth. Nicholson [1872, the presence of the root; Brogger [1882, ] reports that hefound specimens of D. flabelliforme with siculae, the free endof which is pointed, and that that species certainly was notattached, which in all probability may be right for the genus ingeneral. 594 NEW YORK STATE MUSEUM Matthew, who had a large collection of D. flabelli forme fromthe St John basin for investigation, considered it as having had a floatingmode of existence [1891, 9:35]. When, later, G. van Ingen collected somespecimens of the same species for him, which had short rootlets [figured1895, , and 2], he remarked that it might appear from suchexamples as these, that it would be possible to show the existence of asedentary variety or stage in this species; still, it does not seem that thiscondition of the rhabdosome is at all frequent, for among scores that have. Fi» Dictyo nema rarum Wiman. Series of thin sections. t = thecaeor nourishing-individuals; g- = gr>nan<na; k = nuddin$r individuals. From LowerSiluric flint-boulders of Gotland. x53. (Copy from Wiman) been examined since these were found, none with roots have been is further suggested that these processes may have had some other officethan that of anchoring the rhabdosome at the bottom, and thatthey are too short to afford more than a very feeble foothold at thesurface of the soft ooze. Wimans investigations have made us well acquainted with the proximalend of at least one species, D. cavern osum. This [, 25]shows a basal disk, provided with radial ribs, which extend into a kind ofnetwork that would seem to have been -well adapted to fixation on softooze. Wiman came indeed to the conclusion that the Dictyonemas, like all GRAPTOLITES OF NEW YORK, PART 1 595
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