218 
BELAcnir, 
of Towa and Illinois ; Z». ? e.roruatun (iom.eit. p. 108, pi. xi. fig. 14), 
from tho Warsaw Limestone of Illinois; D.? injlexits (turn. cit. 
p. 167, pi. xi. fig. 18), from the Keokuk Limestone of Illinois ; D.? 
Iceolcuh {tom. cit, p. 169, pi. xi. fig. 16), from the Keokuk Limestone 
of Illinois ; and J). mncii-ludovici {tom. cit. p. 161, pi. xi. figs. 2-6), 
from the St. Louis Limestone of Iowa, Illinois, and Missouri. Del- 
todm miffustus, Newberry and Worthen, is also j)lacod hero. 
The genus Chalcodus, Zittel (llandb. Paheont. vol. iii. pt. i. 1887, 
p. 72), from tho German Kupfcrschiofer, though originally referred 
to the CochliodontidsD, does not appear to belong to this family ; 
and a brachiopod shell ' from the Upper Carboniferous of Lo-Ping, 
China, has also been placed here, under tho name of Lcptodiui 
ri('kiIiofeni, E. Kayser (Richthofen’s Beitr. Paliiont. China, 1883, 
p. 161, pi. xxi. figs. 9-11). 
Undetermined Anterior 2'eeih. 
Tho anterior teeth of the Cochliodontidm have been described 
under tho provisional generic names of Jldodvs, Agassiz (Poiss. 
Loss. vol. iii. 1838, p. 104) ; Chomatudvs, Agassiz {tom. cit. 
p. 107); Lojihodus, Romanowsky (Bull. Soc. Imp. Nat. Moscou, 
vol. xxxvii. 1864, pt. ii. p. 160); and perhaps Venusiodiw, St.John 
and Worthen (Pal. Illinois, vol. vi. 1875, p. 344). Those named 
Uehdns planus by Agassiz are known to bo certainly referable to 
Psephodus mat/ints ; and most of the teeth from tho Bristol Bone- 
bed, named Jfelodus loivissimus, doubtless pertain to Psephodus 
lirvissimus. Tho other teeth, however, except //. simplex, are pro- 
bably common to one or more genera or species, and it is thus con- 
venient, upon present evidence, to retain tho provisional determina- 
tions, as follow. Unless otherwise stated, tho specimens were all 
obtained from undetermined horizons in the Carboniferous Lime- 
stone. 
I. Largo elongated depressed teeth, generally with a longitudinal 
elevation near one of the long margins, often rising into a 
median prominence. Such have been described under the 
names of Chomatndus einctus, Agassiz ^ lltlodvs timjidus, 
> Lytfonia, W. Wangen, Paheont. Jndica [13] ])t. iv. (1882), p. 395. 
» Poiss. Foss. vol. iii. (1838), p. 107, pi. xv. ligs. 13-21 (in part). Also 
.1. E. I’ortloek, Rep. Gool. Londonderry (1843), p. 407, pi. xiv.fl. fig. 9 ; L. G. de 
Koninek, Faune Calc. Carbf. lielg. pt. i. (1878), p. 40, pi. iv. fig. 3, pi. vi. figs. 1-5. 
Heludus cincim, P. McCoy, Brit. Palacoz. Foss. (1855), p. 017. 
