. Annual report. New York State Museum; Science; Science. 42 2 NEW YORK STATE MUSEUM Non Climacograptus scalaris Walcott. Geol. Soc. Am. Bui. 1890. i:339 Non Climacograptus scalaris Ami. Can. Geol. Sur. Rep't. Ser. 2. 1889. v. 3, pt 2, Description. Synrhabdosome not observed. Rhabdosome small (10-14 mm long and mm wide), with parallel sides and broadly elliptical section. Sicular and antisicular extremities rounded. Lateral faces possessing slightly undulating median sutures (complete septum). Virgella and free nemacaulus not observed. Sicula small, slender, a little more than 1 mm
. Annual report. New York State Museum; Science; Science. 42 2 NEW YORK STATE MUSEUM Non Climacograptus scalaris Walcott. Geol. Soc. Am. Bui. 1890. i:339 Non Climacograptus scalaris Ami. Can. Geol. Sur. Rep't. Ser. 2. 1889. v. 3, pt 2, Description. Synrhabdosome not observed. Rhabdosome small (10-14 mm long and mm wide), with parallel sides and broadly elliptical section. Sicular and antisicular extremities rounded. Lateral faces possessing slightly undulating median sutures (complete septum). Virgella and free nemacaulus not observed. Sicula small, slender, a little more than 1 mm long. Thecae numbering 10 to 12 in the space of 10 mm; twice bent, first parallel to axis of rhabdosome (first third), then obliquely upward at angle of 300 (second third) and finally again into parallelism to axis of rhabdosome in distal third. Apertural margin oblique, or slightly everted ; apertural excavations triangular notches (one t&M fourth of length and one fourth of width of rhabdosome). 387 Position and localities. Numerous specimens were Fig. 385-87 Climacograp- Ills ', 385', 386n ivJ found in a boulder of ferruginous sandstone, probably views of type specimen, (x 5). .. Fig. 387. Frontal view of thecae ol Clinton ao;e, collected by Mr (Jloi (J. JNylander, and cross-section of rhabdosonie. o ' J J of Caribou, Me. at Aroostook, Me. No associated fossils were This species, which hitherto has not been found in North America, has the distinction of being one of the longest known and most widely distrib- uted graptolites. In Europe it is especially well known from Scandinavia, where it occurs in Scania in the last zone of the Champlainic (Ordovicic) which according to Lapworth is already a basal zone of the Siluric, is especi- ally common in the higher horizons of the lower Siluric (Rastrites shale) and is the index form of the C. scalaris shale. Tornquist records it from the first zone of the Scanian Rastrites beds (zone of Diplogr. acuminat
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