14 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 76 



previously been described that its description and naming seems 

 desirable. 



The undivided carapace, the apparent structure features that appear 

 as elevations on the test and its surface ornamentation all indicate 

 that it is a merostome. If so it is considerably older than any of this 

 group hitherto found. 



Such generic characters as may be observed will be presented in the 

 siDCcific description. 



The name is given as a slight recognition of the important work 

 done for many years by Dr. H. Justin Roddy, now curator of the 

 museum and professor of geology at Franklin and Marshall College, 

 in discovering the interesting fossils occurring in the Lower Cam- 

 brian of the Lancaster region. Doctor Roddy has the happy faculty 

 of interesting people in natural science and therefor the author, 

 together with hundreds of others, owes much to him for his unfailing 

 encouragement in the early years of geologic work. 



Genotype. — Roddyia typa^ new species. 



Range. — Lower Cambrian. Southeastern Pennsylvania. 



RODDYIA TYPA, new species 



Plate 2, figure 5 



Cephalic shield undivided. The prominences noticeable in the 

 specimen may represent a raised central portion lobed somewhat in 

 the manner of Aglaspis.'^'^ Surface covered with slightly irregular 

 raised lines. 



This form should be compared with Molarm.^ B.ahelia.^ and Emral- 

 della of the Burgess shale, but none of these preserve their cephalic 

 shields sufficiently well to make any real comparisons. So far as may 

 be ascertained Roddyia seems to be more like Molaria than the others, 

 but even then the similarity is only superficial. 



Horizon and locality. — Lower Cambrian, Kinzers formation ; (loc. 

 12x) near Rohrerstown, Pennsylvania. 



Eolotype.—Q^t. No. 80480, U.S.N.M. 



10 See Whitfield, 1882, Geol. Surv. Wisconsin, vol. 4, p. 192, pi. 10, fig. 11. 



