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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1898. Excerpt:... Phylloceras onoense Stanton. Plates XIX And XX. Phylloceras ramosum Gabb, PaI. Cal., Vol. I, p. 65, PI. XI, fig. 12; Pi. XII, fig. 12. Phylloceras onoense Stanton, Bull. 133, U. S. Geol. Survey, p. 74. (Not P. ramosum Meek, Bull. Geol. and Geog. Survey Terr., Vol. II, No. 4. P-371 ) This species from the Horsetown beds of the Lower Cretaceous was identified by Gabb with Meek,s species from the Upper Cretaceous of Puget Sound. But Dr. Stanton has recently broken this up into three species in a genetic series, P. knoxvillense Stanton, from the Knoxville beds, Lower Cretaceous; P. onoense Stanton, Horsetown beds, Gault; and the real P. ramosum Meek, from the Upper Cretaceous. Stanton says that P. onoense differs from P. knoxvillense in lacking constrictions, but these were observed on several specimens from Cottonwood creek, Shasta county, and from Alameda county. Ontogeny. Larval stages.--No protoconch was separated from the later chambers, but its shape can easily be seen on Pl. XIX, fig. 1, and Pi. XX, fig. 1. It is very like that of Lytoceras alamedense. The ananepionic stage, shown by the nautiloid septum (Pl. XX, fig. 1), shows a broader and longer abdominal saddle than Lytoceras, but is otherwise like it; the pear-shaped siphonal caecum or knob could be seen clearly inside of the protoconch. The metanepionic stage lasts only through the second septum (Pl. XX, fig. 1); it has an undivided, rounded, ventral lobe, and two external lateral lobes, and probably corresponds to the stock Prolecanitidfe, from which Phylloceras came. With the third septum comes the divided ventral lobe of the paranepionic stage (Pl. XX, fig. 1): this agrees with the Nannites stage of Lytoceras, and probably shows the connection with that genus. This stage lasts up to diameter o...