140 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 75 



DESCRIPTION OF PLATE 21 



PAGE 



Symphysurina zvoostcri Ulrich (MSS.) 115 



Figs. 1,2. (X2.) Dorsal and side views of a fairly complete cra- 

 nidium, showing shape, position and size of eyes and median 

 tubercle. U. S. Nat. Mus., Cat. No. 70309. 



3. (X 2.) Dorsal view of associated free cheek, border broken 



away at genal spine. U. S. Nat. Mus., Cat. No. 70310. 



4. (X2.) Front view of cheek showing extension of rim and 



doublure under front of cranidium. U. S. Nat. Mus., Cat. 

 No. 70311. 



5. (X2.) Broken free cheek, with border removed, exposing the 



peculiar depressions in the under side of the doublure. U. S. 

 Nat. Mus., Cat. No. 70312. 



6. (Natural size.) Free cheek, giving general aspect. U. S. Nat. 



Mus., Cat. No. 70313. 



7. (Natural size.) Another small free cheek, with rim removed, 



more complete than fig. 5. U. S. Nat. Mus., Cat. No. 70314. 



8. (X2.) Associated thoracic segment. U. S. Nat Mus., Cat. 



No. 7031S. 

 '9. (X 2.) Pygidium, general aspect with test preserved. U. S. 



Nat. Mus., Cat. No. 70316. 

 10, II. (Natural size.) Dorsal and side views of the interior cast 



of an associated pygidium. U. S. Nat. Mus., Cat. No. 70317. 



Matrix, white chert. 



Upper Ozarkian, Oneota dolomite. (Loc. 193) : Rudolph's Quarry, 

 Trempealeau, Wisconsin. 



Symphysurina spicata Ulrich (MSS.) 113 



Figs. 12, 12a. (X2.) Dorsal view of a cranidium showing general 

 aspect. U. iS. Nat. Mus., Cat. No. 703^8. 



13. (X 2.) Small broken cranidium. U. iS. Nat. Mus., Cat. No. 



70319. 



14. (X2.) Another small cranidium, poorly preserved. U. S. 



Nat. Mus., Cat. No. 70320. 



15. (X2.) Nearly complete free cheek. U. S. Nat. Mus., Cat. 



No. 70321. 



16. 17. (X 2.) Dorsal and side views of an associated pygidium, 



partly exfoliated. U. S. Nat. Mus., Cat. No. 24647. 

 18. (X2.) Small pygidium. U. S. Nat. Mus., Cat. No. 70322. 



Matrix, thin-bedded limestone. 



Ozarkian, Goodwin formation. (Loc. 201a) : Eureka District, 

 Nevada. 



Symphysurina ? entella Walcott 112 



Figs. 19, 19a. (Natural size.) Cranidium showing course of facial su- 

 ture. U. S. Nat. Mus., Cat. No. 70323. 



20. (Natural size.) Broken cranid'um showing posterior portion 



and palpebral lobes. U. S. Nat. Mus., Cat. No. 70324. 



21. (Natural size.) Free cheek and pygidium referred to this spe- 



cies. U. S. Nat. Mus., Cat. No. 70325. 

 22-24. (Natural size.) Associated pygidia with test more or less 



exfoliated. U. S. Nat. Mus., Cat. Nos. 70326, 70327, 70328. 

 30.. (X2.) Small pygidium. U. S. Nat. Mus., Cat. No. 70329. 



Matrix, limestone. 



Ozarkian, Mons formation. (Loc. 65w) : Clearwater Canyon, 

 Alberta, Canada. 



