NO. 5 CAMBRIAN TRILOBITES 397 



Stratigrapliic range. — All of the species now referred to Blountia 

 are from the Maryville limestone formation of the Middle Cam- 

 brian. 



Geographic distribution. — All known species are from the eastern 

 portion of the state of Tennessee. 



Observations. — The genus Blountia includes a number of small 

 trilobites that apparently came from the same line of descent as 

 Asaphiscns and allied forms. It may be a degenerate from an 

 A sap his c US-like ancestor. The species B. mimula is represented by 

 many cranidia and pygidia and one nearly entire dorsal shield. 



A number of the species are represented by cranidia that might 

 be referred to Anouwcarella Walcott or Liostra&iis Angelin except 

 that they have a general appearance that suggests a different genus. 

 These include all of the following species except B. anser and B. 

 mimula. Blountia mimula has but seven thoracic segments. 



The species referred to the genus are : 



Blountia ? alemon Walcott; Upper Cambrian (pi. 6i, fig. 6). * 



Blountia alethes Walcott; Upper Cambrian (pi. 64, fig. i). 



Blountia ale.ras Walcott; Upper Cambrian (pi. 61, fig. 5). 



Blountia amage Walcott; Upper Cambrian (pi. 64, fig. 3). 



Blountia andreas Walcott: Upper Cambrian (pi. 64, fig. 2). 



Blountia anser Walcott; Upper Cambrian (pi. 61, fig. 7). 



Blountia mimula Walcott; Upper Cambrian (pi. 61, fig. 4). 



BLOUNTIA ? ALEMON, new species 



Plate 61, figs. 6, 6(7 



This is a small species distinguished by a broad glabella, small 

 palpebral lobes, large postero-lateral limbs, and short frontal limbs 

 from other species referred to the genus. The strong occipital fur- 

 row and narrow frontal limb suggest that it belongs to some other 

 genus. The cranidium has a length of 4 mm. 



Formation and locality. — Upper Cambrian : (119 ) ]\Iaryville lime- 

 stone, beneath Nolichucky shale; on Cub Creek, 1.5 miles (2.4 km.) 

 southeast of ^lorristown, Hamblen County. Tennessee. 



BLOUNTIA ALETHES, new species 

 Plate 64, figs. I, la-c 

 This form differs from Blountia mimula in the form of its cran- 

 idium, glabella, palpebral lobes, and its associated pygidium. A 

 large cranidium has a length of 8 mm., and an associated pygidium 

 7 



