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fossils has led to the following conclusioiiH : — 1st, that the distorted 

 Aucella from the Queen Charlotte Islands, also helongs to Mr, Gabb's 

 species, and secondly, that Aucella Piochii itself is most probably con- 

 specific with the European A. Mosquensis, that is, if Eichwald's syno- 

 nymy is to be trusted. The writer has not access to the volume of 

 Leonhard and Brown's " i^eues Yahrbuch," in which A. Mosquensis was 

 first described, nor has he been able to see any European examples of 

 the species ; but some of Mr. Dawson's best specimens almost exactly 

 correspond with the Avicula Fischeriana, as figured and characterized in 

 the "Paleontology of Russia," which latter shell is admitted to be the 

 same as A. Mosquensis. 



According to Mr. G-abb, Aucella Piochii is " very characteristic of a 

 series of shales of the Shasta Group, found from Mount Diablo, at 

 various points along the east face of the Coast Eange, to the north end 

 of the Sacramento Valley. Two or three good specimens from 

 Washington Territor}", east of Puget Sound, were presented by Mr. 

 Samuel Hubbard to the California Academy of Natural Sciences. In 

 Colusa County, east of Clear Lake, I found this shell forming almost 

 the entire bulk of some beds, intersti-atified with the white limestones." 

 At Tatlyaco Lake the rock is also largely made uj) of casts of this 

 species, apparently to the exclusion of every other fossil ; in the Queen 

 Charlotte Islands it seems very rare. In Mr. Eichardson's 1872 col- 

 lections from Vancouvei' Island, there are two specimens of A. Pio.chii 

 labelled " from loose pieces near Victoria," and Mr. G. M. Dawson has 

 recently found another example in a boulder on the same island. 



Aucella Afosquensis has been recorded from many localities in the 

 northern part of the Eussian Empire, and, according to Nordenskiold,^ 

 it occurs also at Spitzbergen. It appears to have been a gregarious 

 mollusk, and is often met with in considerable numbers. Eichwald 

 states that on the margins of the Eiver Jauza, in the city of Moscow, 

 there are banks of shells composed almost entirely of this species. Its 

 exact geological horizon has been the subject of much discussion, and is 

 still doubtful. In the " Geology of Eussia," (18-15) D'Orbigny says that 

 it is characteristic of the " ^tage Oxfordien." Eichwald, in the " Bul- 

 letin de la Societe Imperiale des Naturalistes de Moscou for 1861 and 

 1862," and later in the " Lethea Eossica, 1867," Vol. II., page 520, 

 places it in the Upper and Lower Neocomian. Writing in 1864 and 



» " Sketch of the Geology of Spitzbergen." By A. E' Nordenskiold. Trauslated from the "Transactions 

 of the Royal Swedish Academy of Sciences, Stockholm, 1867." 



