306 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxviii. 



Formation mid locality. — Middle ('and)riaii. Chang" Hsia oolitic 

 limestone, Yen Chuang-, Shantung, China. 



Collections of Mr. Eliot Blackwelder, Carnegie Institution of Wash- 

 ington, Expedition to China. 



IPHIDELLA LABRADORICA UTAHENSIS, new variety. 



The general form of this variety is nuich like that of IpludeUa lahra- 

 dorlea. It differs from it in the tine thread-like concentric striae of 

 the outer sui-face, in this I'espect approaching L aJahonaevsls and 

 /. KaperlKi. 



Foniudioa and loc<d!ty. — ^liddle Cambrian. Concretionary lime- 

 stone above ({uartzitic sandstone, Ophir (!ity, 0(iuirrh Range, Utah. 



IPHIDELLA PANNULA MALADENSIS, new variety. 

 IPHIDELLA PANNULA OPHIRENSIS, new variety. 



In collections from the Middle Caml)rian limestones of northern 

 Utah and southern Idaho, material has been selected for illustration 

 which represents variety of form and surface markings of IjyJiideUa 

 pannula that might be given specific names were it not for the inter- 

 mediate phases which occur at the same locality with the varieties. 

 The specimens from near Maiad Cit}'. Idaho, show a wide variation 

 in outline and surface. Another series from near Ophir Cit}', Utah, 

 illustrate the entire evolution of the ''pannula'"' type of surface, from 

 the concentric striic to the tine network of oblique, raised lines 

 dividing the surface into minute, diamond-shaped depressions. In 

 some examples the ridg-es are so sharp iuid clear that the surface has 

 a honeycomb-like appearance. 



For convenience of reference the species might be subdivided into 

 three varieties : 



Vdvh'iij A. — Surface with pore-like pits, formed l>y oblitjuely crossing, elevated 

 Hues. 



Variety B. — Surface with elevated, sharj) ridges that give it an irregular honeycouib- 

 like appearance. 



Varietij <_'. — Surface formed by raised, concentric lines and ridges that inosculate 

 and become more and more irregular until a tyjiical surface rejjivsented l)y variety 

 A is developed. 



The first variety. A, is typical of the species. For the second 

 variety the name ni(d<idenKls is proposed, and for the third variet}" 

 the term ophirensis. 



Genus KUTORGINA Billings. 



Kutorgrna Billings, l*amphlet; and Geol. Vermont, II, 1S61, p. 948, footnote, 

 figs. 347-349; (leol. Surv. Canada, Pal. Foss., I, 1865, p. 9, figs. 8-10.— David- 

 son, Brit. Foss. Brach., Ill, 1871, p. 342.— Dall, Bull. U. S. Nat. Museum, 

 VIII, 1877, p. 40.— Walcott, Bull. U. S. Geol. Survey, No. 30, 1886, p. 101.— 

 Beecher, Am. Jour. Sci., 3d ser., XLI, 1891, p. 345. — Hall and Clarke, 

 Pal. New York, VIII, 1892, Pt. 1. pp. 90, 1()6, 183; Eleventh Ann. Kept. 

 New York State Geologist, 1894, i>. 247, i)l. iv, figs. 11-13. 



