. Bulletins of American paleontology. 60 Bulletin 150 206 Description of holotype (No. 366, Bureau of Mineral Resources, Geology and Geophysics, Canberra; PI. 4, figs. 1, 3-4).—The holo- type is an internal mould, having a length of 115 mm., of which 58 mm. consists of phragmocone. It has been subjected to dorso-ventral crushing. The lateral diameters at the anterior and posterior ends of the specimen are 91 mm. and 77 mm. respectively. The dorso-ven- tral diameter at the posterior end of the specimen measures 39 mm., and the corresponding diameter at the anterior end 53 mm., but be- cause of
. Bulletins of American paleontology. 60 Bulletin 150 206 Description of holotype (No. 366, Bureau of Mineral Resources, Geology and Geophysics, Canberra; PI. 4, figs. 1, 3-4).—The holo- type is an internal mould, having a length of 115 mm., of which 58 mm. consists of phragmocone. It has been subjected to dorso-ventral crushing. The lateral diameters at the anterior and posterior ends of the specimen are 91 mm. and 77 mm. respectively. The dorso-ven- tral diameter at the posterior end of the specimen measures 39 mm., and the corresponding diameter at the anterior end 53 mm., but be- cause of the crushing, these figures are somewhat lower than the original diameters. The sutures are transverse and sinuous. A pronounced, but relatively narrow saddle occurs across the venter. It is followed by a broad shallow lobe, which gives place to a narrow ill-defined saddle on the ventro-lateral flank. The dorsal surface of the holotype has been crushed, and the sutures are not preserved along this part of the Fig. 11. Suture of Protfrocamcroccras contrarium. At the posterior end of the specimen, the siphuncle has a diam- eter of mm. and appears to have been almost in contact with the ventral wall of the conch. The septal necks and connecting rings are well preserved on the dorsal side but are missing on the ventral side. The septal necks on the dorsal side are excessively thick and short. In a typical siphuncular segment, with a height of mm., the septal necks have a thickness of .5 mm. and a length of .45 mm. At their posterior extremities, the septal necks may generally be seen to bifurcate. The connecting rings are extremely thick and com-. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Paleontological Research Institution (Ithaca, N. Y. ); Columbia University. Ithaca, N. Y. , Paleonto
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