. Annual report . tus intricatus. En-largement of portion ofthe specimen reproducedon , ng\l. x8 Order 2 graptoloidea Lapworth Suborder A graptoloidea axonolipa Freeh, em. Rued- Family dichograptidae auct. em. Freeh STAUROGRAPTUS EmillOllS (= Clematograptus Hopldnson and Clonograptus Hall in part) Emmons proposed, in the second part of his American Geology[1855, ] the new genus Staurograptus for a minute form, which hehad found in the Taconic shales of Rensselaer county, N. Y. His defini-tion of the genus is : Disk free, cruciform, arms four, dichotomous cellsterminal, substance membr
. Annual report . tus intricatus. En-largement of portion ofthe specimen reproducedon , ng\l. x8 Order 2 graptoloidea Lapworth Suborder A graptoloidea axonolipa Freeh, em. Rued- Family dichograptidae auct. em. Freeh STAUROGRAPTUS EmillOllS (= Clematograptus Hopldnson and Clonograptus Hall in part) Emmons proposed, in the second part of his American Geology[1855, ] the new genus Staurograptus for a minute form, which hehad found in the Taconic shales of Rensselaer county, N. Y. His defini-tion of the genus is : Disk free, cruciform, arms four, dichotomous cellsterminal, substance membranaceous, free and furnished with an axis. Thisgenus has, on account of the peculiar aspect, the cruciform division in thecenter and the peculiarly broad dichotomous appendages [see Emmonss twodrawings, reproduced here] of the genotype, S . dicliotomus, been con-sidered as doubtful at the beginning and later suffered still worse fate, for ithas in all newer works on graptolites been delivered to complete £Jr GRAPTOLITES OF NEW 1OKK. PART 1 613 The only note on the genii;-., which is known to ine, is that by Hall[1865, ] which reads: The typical and only species of Staurograptusof the same author is a very remarkable form of extremely minute pro-portions. Its mode of growth and subdivision of stipes, if accurately repre-sented in the figure, are unlike anything known among this family offossils, and it merits generic distinction. Lapworth refers to it [1887, ]as the dubious genus Staurograptus of Emmons. I have now found in the same region whence Emmons obtained thismaterial, in slates associated with the UpperCambric Dictyonema flabelliforme bed, a com-plete series of growth stages [] leadingfrom the sicula through stages identical withEmmonss Staurograptus d i c h o t o m u sto Clonograptus p r o x i m a t u s, aspecies described by Matthew from the Upper mg_u staurograptus aiohoto- . -nt mi l m u s Emmons. Copy of original figures Cambric of the St Jo
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