. Annual report. New York State Museum; Science; Science. GRAPTCL1IES OF NEW YORK, PART 2 183. species of the Quebec group, commenting' on the similarity of the grapto- lites of the Quebec and Niagara periods. It is needless to state more than that there is no such resemblance, the disk-bearing forms of the Quebec group being Dichograptidae. In fact no graptolite comparable to this unique fossil — for the genus contains only one species as yet — has been thus far found on this side of the Atlantic and we must turn to Europe, where in Rodonograptus Pocta, Discograptus and Galeograptus Wiman den
. Annual report. New York State Museum; Science; Science. GRAPTCL1IES OF NEW YORK, PART 2 183. species of the Quebec group, commenting' on the similarity of the grapto- lites of the Quebec and Niagara periods. It is needless to state more than that there is no such resemblance, the disk-bearing forms of the Quebec group being Dichograptidae. In fact no graptolite comparable to this unique fossil — for the genus contains only one species as yet — has been thus far found on this side of the Atlantic and we must turn to Europe, where in Rodonograptus Pocta, Discograptus and Galeograptus Wiman dendroid genera of like habitus have been made known. One or the other of these is likely to be a synonym of Cyclograptus, for they have been erected with- out knowledge of that genus which is not men- stFeniwiman. (XS). c0Py from wiman tioned in their diagnoses. Of Rodonograptus it is stated that it is not sufficiently well preserved to permit a positive decision as to whether there exists "an independent discoidal plate from which the branches proceed or whether this plate has been produced by the compression of the branches which approach each other," the latter being in Pocta's opinion the more probable interpretation, since, " on the best preserved specimens the central disk has no definite ; The drawings of Rodonograptus would seem to support this view. Discograptus and Galeograptus, both genera of Dendroidea from the Borkholmer Schicht in the Baltic region, have distinct disks. We have copied here a drawing of one of each [see text nV. 8q, qoI, since Fig. 90 Discograptus & L O 7»- 7 _l> irom"wimaniman- (x ^ Copy these are made from specimens etched out of flint and therefore give a better idea of the original form of the organisms than the compressed shale specimens from our Niagaran and Clinton rocks. It is obvious that both if compressed would give a picture resembling that of our Cyclograptus. The thecae are in both, Galeogra
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