. Annual report . Theflexuous ami anastomosing course of the branchesforms a character so readily recognized and so dis-tinctive of a group of species, that we have no hesi-tation in recognizing the latter as a genus. This isrepresented in the Deep kill fauna by two species. The presence of occasional dissepiments and ofparts with more straightened branches in D . i n t r i -cat us suggests, however, that the structural differ-ences between Dictyonema and Desmograptus may not be as great as it would appear from their widely Sches in l0e~r part Deep kilLdifferent aspects. Of special
. Annual report . Theflexuous ami anastomosing course of the branchesforms a character so readily recognized and so dis-tinctive of a group of species, that we have no hesi-tation in recognizing the latter as a genus. This isrepresented in the Deep kill fauna by two species. The presence of occasional dissepiments and ofparts with more straightened branches in D . i n t r i -cat us suggests, however, that the structural differ-ences between Dictyonema and Desmograptus may not be as great as it would appear from their widely Sches in l0e~r part Deep kilLdifferent aspects. Of special interest in regard to this relationship is the basal part of the specimen, reproduced in figure 30,which shows in the oldest proximal part parallel branches and true, stoutdissepiments. This Dictyonema structure rather abruptly changes into theDesmograptus structure with irregular and coalescing branches, a changewhich indicates the development of Desmograptus from the typical, alsogeologically older Desmograptus intri-cate us sp. nov! Enlargement ofproximal portion showing transi-tion from straight to undulating 010 NEW YORK STATE MUSEUM Desmograptus cancellatus Hopk. (sp.) Plate 3, figures 5-8 Dictyograptus (Desmograptus) cancellatus Hopkinson. Quar. Jour. Geol. Soc. 1875. 31:668, , fig. 11a, libcf. Desmograptus macrodictyum Gurley. Jour. Geol. 1896. 4:83fDictyonema (Desmograptus) cancellatum Ruedemann. N. Y. State Paleontol. An. Rept. 1902. Description. Rhabdosorne infundibuliform, beginning with a chitinous,apparently nonsiculate basal expansion, and a short stem. Branches thick,undulating, in the proximal part little flexuous and subparallel, distallybecoming gradually more undulating; forming by coales-cence and redivision in the proximal parts long narrowmeshes ; in the distal parts elongate to broadly oval are in the mature parts about twice as wide as thebranches aud three to four times as long as wide. Branches12 to 14 in 1
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectscience, bookyear1902
