371 



costaBj one or two more very obscure ones are seeu, which do not reach 

 either the peripheral or umbilical margin. 



The septa are strongly undulating, and irregularly divided into very une- 

 qual principal and subordinate lobes and sinuses on each side. Siphonal 

 lobe comparatively small, and provided with three short branches on each 

 side, the two terminal of which are a little larger than others, slightly 

 spreading, and merely a little dentate on their margins ; first lateral sinus 

 about twice as large as the siphonal lobe, and very unequally divided into 

 three branches, the outer one of which is largest, and truncated at the end, 

 with four short, nearly simple, subdivisions, while the middle branch is 

 smallest, with merely deeply sinuous margins, and the third one is tripartite 

 and directed nearly inward toward the umbilical side ; first lateral lobe 

 small, slender, very oblique, bipartite, with unequal bifid terminal branches ; 

 second lateral sinus scarcely larger than the oblique branch on the inner 

 side of the first, very oblique, with an extremely contracted body, and 

 two or three alternately-arranged, short, sinuous branches on each side ; 

 second lateral lobe longer than the first, somewhat arcuate, with a slen- 

 der body, a trifid extremity, and three or four short, alternately-arranged, 

 slightly dentate, lateral branches ; third lateral sinus smaller than the 

 second, with a proportionally less contracted body, and about three 

 short, alternating, unequal, nearly simple, lateral branches, and a small, 

 simple, subglobose, terminal division 5 third lateral lobe projecting a little 

 beyond the second, and almost exactly like the first, excepting that 

 its corresponding branches are on the opposite sides ; fourth lateral sinus 

 extremely broad, or more than equaling the breadth of the first, which 

 it also nearly equals in length, slightly divided at the end into two nearly 

 equal, short, broad divisions, with more or less sinuous margins ; fourth 

 lateral lobe nearly as large as the third, but owing to the undulating- 

 arrangement of the whole series, much less prominent, divided at the 

 end into two short, equal, bifid branches, with obscurely dentate mar- 

 gins ; fifth, sixth, and seventh lateral lobes of nearly equal size, and 

 scarcely half as long and wide as the fourth, with merely dentate 

 extremities and lateral margins — all separated from each other by lateral 

 sinuses of about the same size. 



I was at one time of the opinion that the three divisions of the septa 

 here described as the first, second, and third lateral lobes formed, 

 together with the great undulation of the suture with which they con- 

 nect, one enormously-developed first lateral lobe, which would also 

 make the very broad sinus I now view as the fourth, the second lateral 

 sinus. It now seems to me, however, from analogy, on comparison with 

 the sutuves of Placenticeras placenta {= Ammonites placenta, DeKay), that 

 the view taken in the above description of the septa is the proper one. 



The specimen from which the figure and description of this species 

 were made out consists of about one-half of one volution, most of which 

 is non-septate. When entire, the shell must have measured not less than 

 4 inches in its greatest diameter, and about 1.13 inches in convexity. 



Locality iind position. — Komooks, Vancouver's Island; Cretaceous. 



Genus PHYLLOCERAS, Suess. 



Phylloceeas ? RAMOsus, Meek. 



Plate 5, figs. 1, 1 a, and 1 h. 



Ammoiiiies (Scaphife.-i ?) ramosm, Meek (1857), Traus. Albany Institute, vol. iv, 45. — 

 Gabb, (1864) Geological Report of California, vol. i, 65, pi. 11, figs. 12 and 

 12 a • and pi. 12, fig. 12 b. 



Shell oval-discoid in form, compressed, very thin and fragile; narrowly 

 rounded on the periphery ; umbilicus very small, but not entirely closed ; 



