l66 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 64 



The specimens illustrating this species were collected by Mr. W. 

 A. Finkelnburg, of Winona, Minnesota, who presented them to the 

 United States National Museum. 



MILLARDIA SEMELE, new species 

 Plate 28, figs. 3, 3a-c 



The generic description is based on this species as the type. It is 

 represented in the collections by two nearly entire specimens of the 

 dorsal shield and a number of cranidia, which are closely related in 

 form to those of M. optata. 



Formation and locality. — Upper Cambrian: (son) Weeks forma- 

 tion (ic of section);* also (30 o) (ib of section) north side of 

 Weeks Canyon, 4 miles (6.4 km.) south of Marjum Pass, House 

 Range, Millard County, Utah. 



DRESBACHIA, new genus 



General form of cephalon transversely crescentric; the posterior 

 margin arching forward from the lateral margins, strongly convex. 

 Glabella subtriangular in outline and marked by three pairs of 

 oblique, short, deep lateral furrows ; occipital ring strong and 

 sharply defined by a narrow, deep occipital furrow. The frontal 

 limb and border appear to be represented by a narrow projection 

 in front of the glabella that has a deep longitudinal furrow which 

 terminates at a narrow frontal rim. The sides of the furrow appear 

 as though the test had been folded downward, leaving only a narrow 

 strip at the top next to the facial suture. 



On a small cranidium i mm. in length the frontal border projects 

 very much as in Proampyx acuminatum (Angelin), but, unlike the 

 nasute projection of the latter species, it has a longitudinal furrow 

 that extends forward from in front of the glabella, which is the 

 beginning of the deep furrow present on cranidia 3 to 5 mm. in 

 length. 



Fixed cheeks large, elongate, and arched backward ; a strong 

 intramarginal furrow extends from the dorsal furrow beside the 

 glabella out on the cheek, where it fades away before reaching the 

 outer margin. The palpebral lobe has not been seen ; it is probably 

 situated by the side of the narrow projection in front of the glabella 

 or else is very small and located toward the anterior end of the fixed 

 .cheek. As the test is not preserved, there is only the cast in fine 

 sandstone to show details of structure. 



Smithsonian Misc. Coll., Vol. 53, 1908, p. 178. 



