FOSSILS OF THE DEVONIAN. 209 
Pygidium moderately convex, subtrigonal in outline; length two-thirds 
of the width; anierior lateral angles a little rounded, lateral margins con- 
verge with a slight outward curve to the base of a strong upward-curving 
spine that forms the posterior extremity of the pygidum, the spine curving 
up at an angle of 45° in adult specimens and from 35° to 25° in the younger 
individuals; median lobe less convex than the lateral lobes and two-thirds 
as wide, uniformly rounded, and tapering gradually to the posterior extrem- 
ity; marked by 13 to 15 well-defined annulations and an elongate terminal 
ring; lateral lobes with 10 to 11 strongly defined ribs that curve in their 
outer half obliquely backward, terminating just within the narrow margin. 
Surface of the glabella, thoracic segments, and pygidium punctate. 
This is the largest trilobite yet discovered in the Devonian of the West. 
Individuals 35°" in length are indicated by the larger fragments, and one 
hypostoma is 7°" in length. 
The pygidium resembles that of Dalmanites micrurus of the Lower 
Helderberg limestone of New York (Pal. N.Y., vol.iii, p.359, plate Ixxiv, figs. 
13-20), but differs in the less number of annulations in the lobe and in the 
punctate surface. To D. anchiops Green (sp.) (Pal. N. Y., Hlustrations of 
Devonian Fossils, Crustacea, pl. ix) of the Upper Helderberg limestone of 
New York, it has a strong resemblance when compared to young individ- 
uals, but differences exist that readily separate the species. 
The late Mr. F. B. Meek described and illustrated fragments of an 
unknown form of Dalmanites, from the Devonian limestone of the Pinon 
Range of Central Nevada, and the two pygidiz illustrated are closely related 
to those from the Eureka District, the character of the surface, which is 
smooth or granulose, as seen in badly weathered specimens, alone appear- 
ing to be different. 
The specific name is given as a slight recognition of Mr. Meek’s ex- 
tended and valuable contributions to our knowledge of the invertebrate 
Paleontology of the Western United States. 
Formation and locality—Lower horizon of the Devonian limestone, 
Comb’s Peak, and on the divide at the head of the Reese and Berry Camion, 
Eureka District, Nevada. 
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