340 

 Genus Pachydiscus, Zittel (1884). 



A. Normal forms, in which the cast of the interior of the shell 

 is uniformly devoid of transverse and per-iodic constrictions. 



Pachydiscus Otacodensis, Stoliczka. (Sp.) 



Plate 46, fig. 1. 

 Avimonites Oiacodcnsh (pars) Stoliczka. 1865. Cret. Cephal. S. India, vol. i, p. 109, pi. 



Liv, figs. 3 and 4, and pi. lvi (but not pi. lvii) ; fide Kossniat. 

 Pachydiscus Otacodensis, Kossmat. 1894. Jahr. K. K. Geol. Reich sanstalt Wien, vol. 



44, p. 472. 

 Pachydiscus Otacodensis, Whiteaves. 1896. Trans Roj'al Soc. Canada for 1895, Second 



Series, vol. i, sect, iv, p. 181. 

 Pachydiscus Otacodensis, Kossmat. 1897. Beitr. zur Paleeont. Oesterreich-Ungarns 



und des Orients, p. 98 (163, pi. xvi (xxii), figs. 1 a and 1 h ; and 



pi. XVII (xxiii) fig. 1. 



Two specimens from the Vancouver Cretaceous have been identified 

 with this Indian species by Dr. Kossmat. One of these, which the 



writer has not seen, is 



said to be a fine speci- 

 men collected at Nanai- 

 mo, V. I., by Sir James 

 Hector (presumably in 

 1860) and now in the 

 Natura History De- 

 partment of the British 

 Museum. Tiie other, 

 No. 14 of thesmall series 

 of Ammonites sent to 

 Dr. Kossmat, and the 

 original of figure 1 on 

 Plate 46, is a well pre- 

 served specimen collec- 

 ted at Hornby Island, 

 by Mr. F. W. Robbins, 

 in 1895, and presented 



Tig. 20. — Pachydiscus Otacodensis. Outline of transverse ^y him to the Museum 

 section of the outer volution, near the aperture, of the of the Survey. It mea- 

 specimen from Hornby Island represented on Plate 46. gyres about five inches 



and a half in its grea- 

 test diameter, and its aperture is higher than wide, elliptic subovate, 

 but deeply emarginate by the encroachment of the preceding volution. 



