210 FIELD COLUMBIAN MusrEuM——-GEOLOGY, VOL. I. 
were obtained. Some of the specimens although entirely opaque in 
the outer whorls were very translucent in the inner whorls so that the 
suture lines were easily discernible. 
Fig. 1, Pl. XXIII, represents a number of sutures as follows: a. 
The first suture.is angustisellate and represents the ananepionic stage. 
6. The second suture is a transition from the suture of Anarcestes 
to that of Tornoceras. c. The third suture is Tornoceras. a@. The 
fourth suture is a transition from Tornoceras to Glyphioceras, or 
possibly Prionoceras. e¢. The fifth suture is Glyphioceras. f/ Is 
Glyphioceras. g. Is asuture on the second whorl which is Gastri- 
oceras but is just approaching Paralegoceras. 4. Is a suture on the 
third whorl, diameter 5mm., and is the ammonitic radical, probably 
nearest Pronorites. 
The suture on the first part of the fourth whorl has much the ap- 
pearance of the suture of S. warrent, and toward the end of that 
whorl reaches the adult form. 
In Figs. 2, 3 and 4, Pl. XXIII, views of the protoconch are given 
which represent the phylembryonic stage of the type Scaphites 
nodosus Meek. 
Figs. 7-12, Pl. XXIII, represent six stages of growth between 
the close of the brephic and the beginning of the ephebic stage. 
Fig. 5, Pl. XXIII, shows the suture of the adult form of S. 
warrent, and Fig. 6 that of S. nodosus, Museum specimen No. 3653, 
University of Chicago. 
SCAPHITES WARRENI—MEE«. 
Proc. ACAD. NAT. SCI. OF PHILA., P. 185. 1860. 
(Pl. XXII, Fig. rand Pl. XXIII, Fig. 57 Mus:;No.) Pesg4ag} 
REVISED AND ENLARGED Description. ‘‘Shell medium size, trans- 
versely subovate, moderately compressed, inner volutions nearly cir- 
cular, closely involute, and composing a little more than one-half the 
bulk; deflected body portion longer than the diameter of the involute 
portion and rather more proportionally than the inner turns; surface 
costate and without proper nodes; costze small on the inner whorls, 
where they do not differ materially in size, but on the body part 
some, usually every third or fourth one, become more prominent 
than the others, and extend entirely across from the inner side to 
and over the periphery, in passing upon which they bifurcate, or give 
off branches and assume, with these, a uniform size. The aperture’ 
