. Annual report. New York State Museum; Science; Science. GRAPTOLITES OF NEW YORK, PART 2 151 Dictyonema obovatum Gurley Dictyonema obovatum Gurley. Geol. Sur. Ark. Rep't. 1890. 1892. 3:418 Dictyonema obovatum Gurley. Jour. Geol. 1896. 4:300 We have been unable to find the type of this species, in the collection of the National Museum from the Lower Dicellograptus zone of the type locality " near Crystal Springs, ; The species avowedly is based upon but one specimen and this has been described but not yet figured. Dictyonema spiniferum sp. nov. Plate I, figure 4 Description.
. Annual report. New York State Museum; Science; Science. GRAPTOLITES OF NEW YORK, PART 2 151 Dictyonema obovatum Gurley Dictyonema obovatum Gurley. Geol. Sur. Ark. Rep't. 1890. 1892. 3:418 Dictyonema obovatum Gurley. Jour. Geol. 1896. 4:300 We have been unable to find the type of this species, in the collection of the National Museum from the Lower Dicellograptus zone of the type locality " near Crystal Springs, ; The species avowedly is based upon but one specimen and this has been described but not yet figured. Dictyonema spiniferum sp. nov. Plate I, figure 4 Description. Entire rhabdosome not observed. Fragments of rhabdo- some (40 mm long) consisting of subparaHel, straight or but slightly irregu- larly bending branches ; .3—4 mm wide and separated by an interval that is not at all or but little greater. Dissepiments frequent and stout, forming with the branches rectangular meshes, mostly 3 mm long. The thecae are promi- nent, inclined at 300 and number 14 in 10 mm ; their apertures are normal, and furnished with a very acute, horizontal spine about as long as the aperture. Position and locality. Of this species but three specimens have been collected in the Normanskill shale at Glenmont, near Albany; each in other association, viz, with Dicellograptus gurley i, Diplograptus foliaceus and D. angustifolius. Remarks. From the associated dendroid graptolites this form is readily distinguished by its close meshwork and the prominence and dis- tinct spinosity of the thecae. In the form of the thecae and its general habitus it recalls D . furciferum, a Beekmantown shale graptolite. Dictyonema arbuscula (Ulrich) Dictyonema (Hall) James. The Palaeontologist. 1879 Inocaulis arbuscula Ulrich. Cin. Soc. Nat. Hist. Jour. 1879. 2:28, pi. 7, fig. 27, 27a Die ty ogr ap t us reticulatus {nomen nudum) Ulrich. Cat. Foss. Cincinnati group 1880. F>g-. 55, 56 spiniferum sp. nov. Fig. 55 Enlargement of branch showing the thecae in profile vi
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