306 JAMES PERRIN SMITH 
resembles closely P. Attila Mojsisovics, a characteristic form for 
the middle Karnic, zone of 7rachyceras aon in the Mediterranean 
region. The numerous species of Szvenztes all seem to belong to. 
the group of Senticosz, characteristic of middle Karnic; the half 
dozen or more species of Paratropites might belong to either the 
middle or the upper horizon, as might also the species of 
Eutomoceras. But Tropites of the group of 7. Bullat, and Sagenites 
( Trachysagemtes), of the group of S. herbichi Mojsisovics, are 
characteristic of upper Karnic. The writer* previously called 
attention to a part of these faunal anomalies, but their full extent 
was not appreciated at that time. 
In the lower part of the Hosselkus limestone of Shasta county, 
California, there is an undoubted mixture of the middle and 
upper Karnic faunas. This apparent anomaly might be explained 
in two ways. Since 7yopites and its near allies appear as immi- 
grant faunas in the Karnic of the Mediterranean region, the 
Himalayas and California, it is possible that they may have 
reached California earlier than they did the other regions, and 
while the middle Karnic fauna still predominated. Or, on the 
other hand, it may be that Protrachyceras and other members of 
the Zvachyceras aon fauna lived on longer in California than in other 
known regions, so that we have a middle Karnic fauna persisting 
in upper Karnic time. To the writer it seems more probable 
that the Swbdullatus fauna came in earlier, reaching California in 
middle Karnic time, especially since 7vopites seems to have been 
endemic in the Arctic-Pacific region, and since this fauna did not 
all reach California at the same time, but some came in later. 
Thus, Homerites semiglobosus Hauer, and Eutomoceras conf. guin- 
quepunctatum Mojsisovics, which in the Alps occur in the zone of 
Tropites subbullatus, in California occur only at a horizon about 
150 feet higher, and associated with a fauna that is chiefly dif- 
ferent from that of the lower zone. In this higher horizon none 
of the 7vachyerata are left, and the cephalopod fauna consists 
almost entirely of Yvopitidae and Arcestidae, the former being 
represented by Eutomoceras, Tropites, Paratropites, Homerites, and 
* JOURNAL GEOLOGY, Vol. III, No. 4, p. 494. 
