18 I'liOCEEDINGS OF THE NATIONAL MUSEUM. vol. xxi.x. 



HYOLITHES DAPHNIS, new species. 



The t3q3e and only specimen of this species in the collection has a 

 length of 26 mm., with a width at the larger end on the dorsal side of 

 11 mm., and a dorso-ventral thickness of 9 mm. At a distance of 21 

 mm. from the larger end the smaller end has a width of 5 mm. on the 

 dorsal side. Nothing is known of the outer surface. The section 

 shows a very strongly convex ventral side, with rounded ventral 

 angle; the dorsal side is gently convex, with the lateral angle slightly 

 rounded. 



This species is represented b}^ a cast that might have been taken 

 from some of the more convex specimens of Jlyolithes princess Bil- 

 lings, of the Lower Cambrian rocks of Newfoundland. It differs 

 from these in the more convex dorsal side. 



Formation and locality. — Upper Cambrian, summit of the Chao Mi 

 Tien formation; 2.7 miles southwest of Yen Chuang, HsinTai, Shang- 

 tung, China. 



Collected by Eliot Blackwelder, of the Carnegie Institution of 

 Washington Expedition to China. 



HYOLITHES DELIA, new species. 



This species is represented by the dorsal side of a single specimen. 

 It resembles the dorsal side of Jlyolitltes hUlmgsl Walcott." The 

 dorsal surface is gently (convex and is marked on each side, parallel 

 to and a little distance within the margin, by a very shallow groove 

 which outlines a central, more slightly convex area. This specimen 

 is probably the interior cast. It shows a few forward-arching concen- 

 tric lines of growth. The type and only specimen representing the 

 species has a length of 5 mm., with a width of 1 mm. at the smaller 

 end and 2.25 mm. at the larger end. 



From the means of comparison afforded by the single specimen this 

 species appears to be most closely related to iryoUthes hiUlngsL It 

 differs in the more slender tube. 



Forii\a,tlon and locality. — Lower Cambrian, in hard, blue-gray 

 limestone, lower part of Man To farmation; 2.5 miles south of Yen 

 Chuang, Hsin Tai, Shangtung, China. 



Collected by Eliot Blackwelder, of the Carnegie Institution of 

 Washington Expedition to China. 



Genus ORTHOTHECA Novak. 



ORTHOTHECA CYRENE, new species. 



Form, an elongate, slender, subtriangular tu))e, with the lateral mar- 

 gin rounded, tapering gradually from the base to an acute extremity. 



«Bull. No. 30, U. S. Geol. Survey, lcS86, p. 134, pi. xiii, figs, lb, le. 



