Trilodites of iHE Chazv Limestone. 385 



Plate 12. 



1. hoteliis obtKsus Hall. Outline of a complete specimen. 



2. The same species. A pygidium and five thoracic segments. 



3. Isolelus harrisi Raymond. An imperfect free cheek, showing the genal spine. 



4. I'he same species. A small cranidiuni. 



5. The pygidium of a large individual of this species. 



6. The same species. Ilypostoma. 



7. .Side view of another hypostoma. 



8. Asaphiis, species alpha. I'ygidium, enlarged four diameters. 



9. Asaphiis, species beta. Pygidium, enlarged two diameters. 



10. Asaphiis, species gaiiima. Pygidium, enlarged four diameters. 



Plate 13. 



1. IlLnius indcienninatiis Walcott. 



2. The same species. A free cheek. 



3. Isolelus angiislicauda Raymond. A pygidium. 



4. The same, side view. 



5. ThaU'ops ovatiis Conrad. An entire specimen, the test broken from glabella 

 and pygidium. Enlarged two diameters. 



6. llLemis globosiis Billings. A small cephalon. 



7. Thorax and pygidium of a larger individual of the same species. 



8. IlLcuiis erastiisi Raymond. A cephalon of average size. 



9. Pygidium of the same species. 



10. Illi£niis piinctatits Raymond. A small specimen, the cephalon distorted by 

 pressure, enlarged two diameters. 



11. llliLiiiis bayfitldi Billings. Cephalon of one of the typical specimens. 



12. Thorax and part of pygidium of the same. 



13. Pro'etus clelandi Raymond. Cranidium of the type specimen, enlarged two 

 diameters. 



14. I'rotile view of the same, enlarged two diameters. 



Plate 14. 



1. Platymelopus mitiganeiisis Billings. A cranidiuni, natural size. 



2. The same species. A small pygidium, imperfect at the front, one third larger 

 than natural size. 



3. The same species. Outline of hypostoma, twice natural size. 



4. Glaphiirits pustiiladis Walcott. A cranidium and part of thorax. Chily such 

 spines as show on a single specimen are represented. Twice natural size. 



5. The pygidium of a large individual of the same species, enlarged three 

 diameters. 



6. The same species. \n hypostoma, enlarged three diameters. 



7. Glaphttrus prii/uis Raymond. Glabella and portion of fixed cheeks, enlarged 

 two diameters. 



8. Free cheek of Glaphurus primus, enlarged two diameters. 



9. Cvbi'le 7'alcourensis Raymond. The pygidium, enlarged four diameters. 

 10. Amphion tanadetisis Billings. Dorsal view of an entire specimen. 



