348 



The pair of large nodes on the ventrolateral angles of each rib is the 

 most conspicuous feature of this shell, and one which will readily distin- 

 guish it from all the described American species of Pachy discus. Dr. 

 Kossmat, who has seen the type specimen from Comox, thinks that it is 

 quite distinct from any Indian or European species known to him, and 

 that it is one of the most peculiar types of Pachydiscus in the Vancouver 

 Cretaceous. 



B. — Ahei'rant species, in tvhich the cast of the interior of the 

 shell is usually marked tvith transverse periodic constrictions. 



Pachydiscus Newberryanus, Meek. (Sp.) 



Avimonites Nexvberryanus, Meek. 1857. Trans. Albany Inst., vol. iv, p. 47 (not A. New- 



berri/anus, Gabb, 1864, Geol. Snrv. Calif., Palseont., vol. i, 



p. 61, pi. 27). 

 ., 1. Meek. 1876. Bull. Geol. and Geog. Surv. Terr., vol. ii, p. 367, 



pi. 41, figs. 3, 3 «, h. 

 I, M Whiteaves. 1879. This volume, pt. 2, p. 109, pi. 15, figs. 1 



& 1 «. 

 Desmoceras Newherryannm, Whiteaves. 1893. Trans. Royal Soc. Canada for 1892, vol. x., 



sect. IV, p. 114. 

 Pachydiscus Newherryanus, Stanton. 1896. Bull. U.S. Geol. Surv., No. 133, j). 16. 



The original type of Ammonites Newherryanus is from Nanaimo, Y.I., 

 where it appears to have been collected by Mr. J. M. Turner in 1856. 

 The specimen described and figured under that name by Meek in the 

 Bulletin of the Geological and Geographical Survey of the Territories is 

 from Comox, V. I., and was probably collected there by Mr. George Gibbs 

 in 1858. It is said to be " 2-28 inches in its greatest diameter " and its 

 surface markings are thus described: " Surface ornamented by distinct 

 rounded costse, which occasionally bifurcate near the umbilicus, and 

 about half-way across toward the periphery, in crossing which they curve 

 slightly forward ; depressions between the costse generally about equaling 

 the latter in size, but at intervals of about five or six times to each turn, 

 a deep sulcus or constriction is seen on internal casts, produced by the 

 occasional thickening of the lip, at regular intervals of about every fifth 

 of each turn. A single row of small transversely elongated nodes sur- 

 rounds the umbilicus." 



1. — Typical form, in which the periodic constrictions are well defined. 



On Vancouver Island, specimens that are apparently referable to the 

 typical form of this species were collected by Mr. Richardson, at Brown's 

 River (a tributary of the Puntledge or Comox River), and the lower part 

 of the Trent River, in 1871, and at North West Bay in 1873 ; also by 

 Mr. Harvey, on the Nanaimo River, in 1901. Similar specimens have 



