544 Systematic Paleontology — Upper Devonian 



single rows, much thickened, with generally quadrangular outline and 

 convex surface, each projecting on the margin of the ray. At each axilla 

 is a single pear-shaped plate with its apex outward, these plates being the 

 largest in the individual. The abactinal surface is tessellated by rows of 

 strong convex plates of similar size to the marginal plates. Of these 

 there are three rows, a median row of narrow oval ones between the ends 

 of which are interlocked the edges of the much larger plates of the 

 lateral rows which are highly convex and thickened in the center and 

 greatly depressed to the sutures. Thus each plate has a cushioned sur- 

 face. Between the ends of each plate of the middle row are two minute 

 accessory plates lying in the angles at which the lateral plates enter. At 

 the base of each ray and upon the disk is a single large plate whose 

 surface rises into a high clavate node. Between each two of these is one 

 of less height. The central portion of the aboral area is destroyed and 

 no trace of madrepore is seen. 



The width of this specimen from tip to tip is 33 mm. 



Occurrence. — Jennings Formation, Chemung Member. Yellow 

 sandstone on the road northeast of Oakland, Garrett County, wliere it is 

 associated with Spirifer disjunctus. 



Collection. — Maryland Geological Survey. 



VERMES 



Class ANNELIDA 



Subclass CHAETOPODA 

 Order POLYCHAETA 



Suborder TUBICOLA 



Genus SPIRORBIS Lamarck 



Spirorbis gyrus n. sp. 



Plate XLVI, Fig. 5 



Description. — Tube closely coiled, attached by one side of all the 

 wbnrl?. tlie final wlioi'ls not boconiing lax. Volutions 2-3, ascending on 



