FAUNA OF THE TRENTON GROUP. 
27 
Genus, Clitambonites Pander. 
Clitambonites trentonensis sp. nov. 
Plate YIII, figures 6, 7. 
Clitambonites diversa Winchell and Schuchert, Pal. Minn., vol. 3, pt. 
1, 1803, p. 378, PI. 30, figs. 11-17. 
Clitambonites americanus Hall and Clarke, Pal. New York, vol. 8, 
pt. 1, 1892, p. 239, PI. 15A, figs. 1-4, 7, 8. (Not 5, 6.) 
The well-kniown Clitambonites of the Trenton of Ontario and 
Minnesota seems still to be without a name. Realizing that it was 
probably distinct from the Richmondian species from Anticosti, 
authors have lately been referring to it as Clitambonites americanus, 
under the impression that Whitfield’s specimens were from the 
Trenton. Baseler has, however, recently stated that G. americanus 
is from the Richmond. 1 
In any case, the specimen figured by Whitfield is of quite a dif- 
ferent shape from the majority of the specimens found in the Trenton 
at 'Ottawa, and very like C. diversus from Anticosti. 
In Clitambonites trentonensis the greatest width is at the hinge, 
the shell is appreciably wider than long, the cardinal area of the 
pedicle valve is high, flat, curved, or twisted, the pedicle shell symme- 
trical or distorted, the brachial valve gently convex or fiat. The sur- 
face is marked by coarse, radial striae which increase both by im- 
plantation and bifurcation. 
The species differs from C. diversus and C. americanus in being 
much wider and of smaller size. Prom G. multistriatus Foerste 3 
it differs in having coarser striae and a more extended hinge. From 
Clitambonites rogersensis Foerste it may he distinguished, according 
to Foerste, by having longer muscle-scars in the brachial valve, and, 
judging from his figures, by the more extended hinge. 
Locality . Fairly common in the middle Trenton around Ottawa 
and in central Ontario. It also occurs in Minnesota, where one 
stratum characterized by it is known as the Olitambonites bed. 
Clitambonites ruedemanni sp. nov. 
Clitambonites americanus Rnedemann, Bull. New York State Mus., 
162, 1912, p. 94, PL 4, figs. 14-19. 
The specimens from the Snake Hill beds of eastern New York 
were identified by Foerste with Clitambonites americanus, but they 
differ very markedly from that species and also from C . trentonensis 
ITJ.S. Nat. Mus. Bull. 9i2 v 1915, p. M4. 
2 Bull. Sc. Lab., Denison TJnlv., vol. XVIT, 1912 1 , p. 131, PI. lO, fig. Ii2, 
10711 — 4 £ 
