21 



(which happciis to he' water-woi'n in the original) is represented as^ 

 too narrow and acute. 



Aininonites Perezianus is neai'ly rehited to A. (^Oppelia) sabcostaria ^^ 

 Op})el, and particidarly to A. (^Oppcli(i) Waageni of Zittel. The former 

 is represented as having a more rectangular iimhilicus than A. Perezianus 

 as well as fewer and more distant folds on the sides of the outer whorl. 

 Both have thicker shells than the species just described, and A. Waageni 

 is depicted as having an entirely smooth surface. On the other hand, 

 the only specimen of A. Perezianus jet procured is a little crushed, 

 and there is reason to suppose tluit its whorls were thickest near their 

 middle, so that the shape of the shell was nearly, if not quite, lenticular 

 in its normal state. Even supposing this to have been the case, A. 

 Perezianus is a thinner and flatter shell than A. Waageni, and the 

 difference between the sculpture of the two may be of specitic import- 

 ance. Under all the circumstances, it seems desirable to propose a 

 provisional name for the species, and the one suggested is intended to 

 help to perpetuate the memory of the first discoverer of the islands at 

 which the fossil was collected. 



Ammonites Brkweiiii Gabb. 



Plate 1, figures 2, '2a, and 3, 3a. 



Ammonites Brewerii Gabb. — "PaL-eontology of California," Vol. I., page 62, Plate X., 

 fig. 7. Also Vol. II., page 130, Plate XX., fig. 5. 



The Ammonites from the (^ueen Charhjtte Islands which are believed 

 to belong to this .species, present two sti'ongly marked varieties. The 

 specimen represented at fig. 2 f is the largest individual of what may be 

 fairly regarded as the tj'pical foi-m, as it corresponds exactl}" with Mr. 

 Gabl)'s amended description of his A. Brewerii^ although the original 

 figures of the adult have a stronglj^ ribbed surface, whereas that of 

 normal examples collected by Mr. Richardson is either smooth, or orna- 

 mented only by faint, sinuous, transverse striae Figure 3, on Plate I., 

 is a jjortrait of the most perfect of two specimens of what seem to be a 

 dwarfed variety of this shell, presenting (diaracters, (such as a compara- 

 tively large umbilicus, sti-ong j-ib-like folds, &c.) which are usually only 

 seen in much larger individuals. It will be convenient to consider each 

 form separately, and as the only work in which J.. Breiceriiwa^ described 



* " Geognostich-Palaiontolofrigche Beitrage." Von Dr. E. W. Benecke. ZweiteiBand. Heft 2, page 219 

 Plate XIX., figs. 2-5. t On Plate I. 



