162 THE DEVONIAN OF MISSOURI. 



narrow, impressed and scarcely widening upon the cheeks; occipital ring moderately 

 broad, somewhat flattened and of about the same width along the posterior margin. 



Eyes relatively large and somewhat elevated above the surface of the glabella. 



Thorax composed of ten segments. 



Pygidium rounded sub-triangular, slightly produced at the extremity; length to 

 width as 1 to 1.5. Surface convex, sloping evenly to the lateral and posterior margins. 

 Composed of eleven or twelve flattened, transverse annulations. Pleurae broad and 

 evenly rounding to the margins; bearing from eight to eleven annulations, each being 

 grooved by a faint impressed line, which is most distinct near the axis and toward the 

 margins. The border is moderately broad and thickened, widening to the posterior 

 extremity, the annulations, with the exception of the first three or four becoming extinct 

 upon reaching its inner margin. Surface smooth or minutely granulose." 



Remarks — Three imperfect cephala and several nearly perfect pygidia have been 

 collected in Missouri. The pygidia differ slightly from Hall's figures in the glabella 

 not narrowing so abruptly toward the front. The pygidium proportion is about 1 to 

 1.3 rather than 1 to 1.5 as in Hall's specimens. 



Occurrence — Grand Tower limestone of Little Saline Creek, Ste. Genevieve County. 



Proetus sp. undet. 



Fragments of two other species of Proetus from the Grand Tower of southeastern 

 Missouri are in the collections of Walker Museum, but it is impossible to make specific 

 determinations from them. 



Order PROPARIA 



Family Calymenidae 



Geuus Homalonotus Koenig 



Homalonotus sp. undet. 



A few fragments of this genus have been collected from 3 miles south of St. Marys, 

 Perry Cdunty, St. Laurent limestone. 



Family Phacopidae 



Genus Dalmanites Barrande 



Dalmanites sp. undet. 



Fragments of this genus have been collected from the Grand Tower limestone on 

 Little Saline Creek. 



Genus Cryphaeus Green 



Cryphaeus boothi Green 



Plate 39, figure 10. 



1837. Cryphaeus Boothii Green, Am. Jour. Sci., XXXII, p. 343 and figure. 



1888. Dalmanites (Cryphaeus) bootht Hall and Clarke, Pal. New York, VII, pp. 42-45, 



pi. 16, figs. 1-4; pi. 16a, figs. 3-8. 

 1910. Cryphaeus boothi Grabau and Shimer, North American Index Fossils, II, p. 



329, fig. 1648 a-b. 

 1913. Dalmanites (Cryphaeus) boothi Prosser and Kindle, Maryland Geol. Surv., 



Middle and Upper Devonian, pp. 333-334, pi. 44, figs. 1-4. 

 Prosser and Kindle' s description — "General form suboval, laterally and posteriorly 

 fimbriate; length about one-half .greater than the width; surface depressed-convex, 



