340 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
The Kaugatoma formation is of Ludlow age, and has many faunal 
elements in common with rocks of that division in both Scandinavia 
and Great Britain, but with the Norwegian section the common spe- 
cies are not so many as desirable. Species of high diagnostic value 
which also occur in the Kristiana region of Norway in strata of Ludlow 
age (Kiaer’s stage 9) are Camarotoechia nucula, C. borealis, Chonetes 
striatellus, Retzia saltert, Spirifer elevatus, Grammysia cingulata, Megalo- 
mus gothlandicus, and Cardiola interrupta (occurs in the strata of the 
preceding stage 8). 
In the English Ludlow the same (Megalomus gothlandicus excepted) 
and other additional species occur, among the latter being Aviculo- 
pecten danbyi, Cardiola interrupta, Orthonota cymbaeformis, Orthoceras 
bullatum, Crotallocrinus rugosus, and also numerous eurypterids, some 
.of which are closely related to those of the Oesel formation. While 
the identifications of some of the species named above are perhaps 
erroneous, enough are certain to assure synchroneity. 
With the North American section the Oesel formation has few spe- 
cies in common and these are of almost universal distribution and of 
long range. The fauna of the Eurypterus beds, however, affords a 
most important point of faunistic contact. Schmidt first identified 
the common eurypterid (E. fisheri)’as E. remepes De Kay and later 
both he and Holm agreed that it is little more than a geographic 
variety of the latter.1 E. remipes is the common form of the Bertie 
Waterlime of the Salina group of New York and in addition to these 
two forms, there are others which are closely related. If then, the 
Sagaristi zone and the Bertie Waterlime be considered synchronous, 
it follows that the Kaugatoma zone finds an equivalence in the Coble- 
skill, Rondout Waterlime, and Manlius limestones.’ 
1Schmidt. Bull. Geol. soc. Amer., 1892, 3, p. 59. 
2 No correlation has been made with the Gotland section for the reason that the data are not 
well enough in hand to warrant the attempt. 
