202 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 64 



Dr. Owen describes the genus Crcpicephalus (1852), but does not 

 mention a species as the type species or apply the name to the form 

 which he describes generically. He refers in his generic descrip- 

 tion to several figures; the first is figure 16 of plate lA. This has 

 in it two pygidia and two cranidia of C. iowensis. He also refers to 

 figures 10 and i8 of the same plate, both of which have a cranidium 

 of C iowensis on the rock. 



The associated pygidia that he refers to and illustrates by figure 

 8 of plate I and figure 16 of plate lA both belong to C. iowensis. 

 Apparently by error, Dr. Owen placed the species C. iowensis under 

 the genus Dikelocephalus and in the description of the plate as 

 Dikelocephaliis ? iowensis. 



In view of the references to the figures in the generic description, 

 and evident error in referring the species iowensis to the genus 

 Dikelocephalus, the cranidium of which it does not resemble in any 

 respect, I think we should assume without question that the species 

 iowensis is the type of the genus Crepiccphalus. 



It is also to be noted that in the description of figure 13, plate I, 

 by Owen, the species wisconsensis is referred with a query ( ?) to 

 the genus Crepicephalus. No reference, however, is made to that 

 species in the text. 



Messrs. Hall and Whitfield, in describing Cambrian trilobites 

 from Utah and Nevada, discussed the genus Conocephalites and 

 revived Crepicephalus as a subgenus equivalent to Loganellus of 

 Devine. They did not, however, describe the genus Crepicephalus, 

 but referred a number of species to it which possess more or less 

 distinctly marked " slipper-shaped " glabella. Prof. Whitfield sub- 

 sequently used the genus in his description of Crepicephalus (Logan- 

 ellus) montanensis^ in the Paleontology of the Black Hills of 

 Dakota." But later (1882) he omitted reference to Loganellus in 

 describing Crepicephalus onustus.^ 



Stratigraphic range. — Lower Cambrian : Upper beds : C. augusta, 

 C. liliana. 



Middle Cambrian : C. convexus, C. damia, C. magnus, from China ; 

 C. coosensis, from Alabama. 



Upper Cambrian : C. iowensis, C. camiro, C. comus, C. coria, 

 C. texanus, C. texanus danace, C. texanus elongatus, C. thoosa, C. tri- 

 punctatus, C. tripunctatus wagnispinus, C. tumidus, C. unca, C. unzia, 

 C. upis, C. undt. spp. 



Bull. U. S. Geol. Survey, No. 30, 1886, p. 141. 



'Rept. Geology and Resources of the Black Hills (Jenney), 1880, pp. 341-343. 

 ' Geol. Wisconsin, Vol. 4, 1882, p. 182. 



