402 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 53 



DESCRIPTION OF PLATE 34 



PAGE 



Pcedeumias transiians, new genus and new species (See pis. 24, 25, 32, 33, 



41, and 44) 30s 



Fig. I. Elongate form of dorsal shield from locality (25), at Parkers 

 quarry, Georgia, Vermont. X 2. U. S. National Museum, 

 Catalogue No. 568086. 



2. Elongate form of dorsal shield from York. X 2. U. S. Na- 



tional Museum, Catalogue No. 56810(7. 



3. Broad form of dorsal shield from York. X i-S- U. S. Na- 



tional Museum, Catalogue No. 56810/'. 



4. A dorsal shield 12 mm. in length with 13 thoracic segments 



and long terminal telson from York. X 3- U. S. National 

 Museum, Catalogue No. 56810.?. 



5. Hypostoma attached to doublure by a narrow median support. 



From York. X 2. U. S. National Museum, Catalogue No. 

 56810?. 



6. Cephalon with the doublure and hypostoma separated and turned 



back on the line of the intergenal spines. From York. X 2. 

 U. S. National Museum, Catalogue No. 5681OM. 



7. Hypostoma attached to doublure by a narrow median support. 



From York. X 3- U. S. National Museum, Catalogue No. 

 568 1 oz;. 



The specimens represented by figs. 2-7 are from locality 

 (8(7) 2 miles northwest of York, Pennsylvania. 



8. Hypostoma from locality (17a) near Montevallo, Alabama, 



showing perforated posterior margin. X 3- U. S. National 

 Museum, Catalogue No. 56811a. 



Olenellus thompsoni (Hall) (See pis. 35 and 44) 336 



Fig. 9. A flattened dorsal shield from locality (25), Parkers quarry, 

 Georgia, Vermont. Natural size. U. S. National Museum, 

 Catalogue No, 15418a. 



Figure 9 is redrawn from the specimen figured by Walcott, 

 1886, pi. 17, fig. 2. 



