PLATE XIV. 



PAGE. 



Figs. 1-3. Prcetus precursor Herrick 509 



1. Head and portion of thoracic segments. Cuyahoga shale, Moot's run, LickingCo. 



2. Glabella of the same species. 



3. Facets of the eye prominence, magnified. 

 Figs. 4-5. PHvETHONiDES spinosus Herrick. 



■4. Glabella and portion of the head, twice natural size. Cuyahoga shale, Licking"and 



Ashland counties. 

 5. Pygidium of the above. 



Fig. 6. Phillipsia meramecensis Shumard. 



Pygidium, enlarged two diameters. 

 Fig. 7. Prcetus minuTus Herrick. 



7. Greatly enlarged. It is probable that this is a young specimen of Proetns prgecur- 



sor. Intermediate forms show that the length of the axial portion of the glabel- 

 la varies with age. This specimen is almost microscopic. Moot's run. 

 Fig. 8. Phillipsia SERRaticaudata Herrick. 



8. P3'gidium and its markings. 



Srf. Portion of head. Upper Keokuk) layers ofWaverly at Newark. 

 Fig. P. Ph^ETHonides immaTURUSt Herrick. 



Pygidium. Probably immature or depauperate forms of P spinosus. This form 



occurs in the shales, while the typical specimens are from the lime concretions 



of the same strata, Cuyahoga shale, Cu3'ahoga Falls, 40 feet below the coal 



measure conglomerate. This form is generally labeled P. lodiensis by collectors. 



Figs. 10-11. Ph^EThonides occidentals Herrick. 



a. Portion of head, enlarged two diameters. 



b. Pygidium, natural size. Kinderhook division conglomerate I ) Granville. 

 11. Hyposiome of some trilobite. perhaps Phillipsia seraticaudata Herrick. 



Fig. 12. Prcetus sp? (perhaps haldemaui). 



Shales near base ofWaverly, one mile east of Harlem, Licking con nty 



Fig. 13. Prcetus i?). 



Portion of head from the upper division. 

 Figs. 14-15. PrcETUS auriculatus Hall. 



14. Reduced one-half. Kinderhook freestone, near Grativille. 



15. Pygidium of unknown trilobite (perhaps Phrethonides from upper division Bur- 



lington near Newark. 



Fig. 16a. Prcetus precursor Herrick. 



A ralher immature specimen. Cuyahoga shale Lodi, Ohio. 

 Fig. I6d-c. Ph.ETHonides spinosus Herrick (?). 



Pygidium apparently of this species from shales of Cuyahoga strata at Lodi. In 

 the fourth volume of the Bulletin of Denison University these pygidia and the 

 associated heads were recognized as a distinct species .Phillipsia? cousors) but 

 the attempt to unite the characters of two genera should not have been made. 

 We have since found the forms connecting such glabellas with typical Prcetus 

 prasmaturus, which species is typically represented in the concretions at the 

 same place. The pygidia can hardly be other than depauperate forms of P. spi- 

 nosus of the same horizon. 



