54 Tin American Geologist. July, 1898 
a small fossil from the "Coralline beds of the Upper Magne- 
sian Cliff Limestone of [owa and Wisconsin," under the name 
«>!' Lunulitesf dactioloides. The report was printed in June 
is |<>. and was reprinted with some additions and emendations 
in ISli, The fossil in question, Lunulitesf dactioloides, is 
described briefly, as follows, on page 68: Truncated spheri- 
cal, with live or six sided cellular depressions in rows around 
the circumference, like those on a thimble, one inch and a 
quarter in circumference." The illustration of the species, 
figure I. plate xiii. exhibits a fossil with a spherical surface 
marked by rounded pits arranged quincuncially. The pits 
are relatively large and separated from each other by thick 
walls. Owen's figure is indeed a very imperfect illustration 
of the fossil as we now know it; and were it not for the text 
which describes the cellular depressions as five or six sided. 
and the fact that no other spheroidal fossils having the sur- 
face marked by polygonal depressions are known from the 
horizon of the Niagara limestone, the forms we have studied 
might never have been identified with Owen's species. The 
identification was first made by Meek and Worthen who, in 
the Geology of Illinois, vol. iii, page 845, give the results of 
their study of this species under the name of Pasceolus? 
dactylioides Owen. They recognize the difference between 
the form they describe and Billings' genus Pasceolus, but 
;ut deciding the zoological relationship of the form un- 
der consideration, and even without settling the question of 
whether it was an external or internal cast, they propose for 
it the new generic name of Cerionites. 
In the fourth volume of the Geology of Wisconsin, page 267, 
Prof. R. P. Whitfield effects another change in the spelling of 
the specific name, and discusses the characters of the species 
in question under the head of Cerionites dactyloides Owen, 
although in the description of plate xiii, Whitfield allows the 
name to stand as Cerionites dactiloides. 
Concerning the specific name I think it must be evident 
that Owen intended to use a term implying, not that the fossil 
described was like a finger, but that it was like n thimble — 
something to put on the finger. The word that comes uearesl 
to standing for thimble may lie spelled with our Roman let- 
ters dactulios from which we may derive dactilioides, the form 
