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IOWA ACADEMY OF SCIENCE Vor,. XXIX, 1922 
pugnus (Martin). This name was first applied to a European 
species which occurs abundantly in the Lower Carboniferous 
(Mississippian) of the British Isles and the Continent, but less 
commonly in the subjacent Upper Devonian beds of the same 
countries. Species identified as R. pugnus or P. pugnus and varie- 
ties have been reported from several Devonian localities in North 
America. In the opinion of the writers these need revision. 
The fact that R. alt a and R. pugnus are the names heretofore 
attached to rather similar shells from Iowa naturally has led to 
some confusion. By some authors R. alta is made synonymous with 
R. pugnus, by others, it is regarded as a variety. Thus Walcott and 
later Whiteaves in the works cited above make these synonymous 
while Williams 6 makes alta a variety but actually figures R. 
pugnus from the State Quarry beds at Solon. On the other hand 
Hall and Clarke , 7 the authors of the genus Pugnax, refer both the 
Lime Creek and State Quarry species to Pugnax altus Calvin and 
illustrate both forms with excellent figures which bring out clearly 
some of the differences between the Hackberry Grove and Solon 
species. Schuchert 8 in his bibliography lists R. alta as a variety 
of Pugnax pugnus and limits it to the one locality, namely Solon. 
Weller 9 regards the two as similar and assigns Pugnax altus to 
both the State Quarry and the Lime Creek. But it is needless 
to add further examples from the literature of the obviously badly 
confused identification of these two quite distinct forms. Calvin 
clearly recognized their differences but unhappily he lacked con- 
sistency in the use of the names. In the Cerro Gordo list 10 he 
correctly enters the Lime Creek species as Pugnax altus but in the 
Buchanan county list 11 of the Independence shale fossils he enters 
a brachiopod which he considered identical with the Lime Creek 
species as Rhynchonella ( Pugnax ) pugnus var. alta and speaking 
of its occurrence he says, “the Rhynchonella ( Pugnax ) pugnus, 
found in both the Lime Creek and the Independence shales, is a 
small acuminate variety, quite distinct from that occurring in the 
State Quarry beds of Johnson county, Iowa.” The distinctness 
of the two in Calvin’s opinion is further brought out in the John- 
son county report 12 where he says “the fauna of the State Quarry 
6 Williams, H. S., Bull. G. S. A., Vol. I, p. 495, pi. 12, figs. 5 - 7 , 1890. 
7 Pal. N. Y., Vol. VIII, pt. ii, pp. 203, 204, pi. PX, figs. 1-5, 1894. 
8 Opus cit. i 
9 Jour. Geol., Vol. XVII, p. 266, 1909. 
10 Iowa Geol. Survey, Vol. VII, p. 165, 1897. 
11 Iowa Geol. Surv., Vol. VIII, pp. 223-224, 1898. 
12 Iowa Geol. Surv., Vol. VII, p. 78, 1897. 
