324 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 64 



small pygidium which appears to me to belong to C. spinttlosus, and 

 of which for this reason I give a figure (pi. 55, fig. ib) and describe 

 it. Pygidium semicircular in form, with an entire margin. Median 

 lobe about five-sixths of the entire length of the pygidium, curved, 

 with three rings, which on the flat lateral lobes are continued by two 

 broad, indistinct ribs, which alternate with the annular or the rings 

 of the median lobe. Along the posterior margin of the pygidium 

 there is a flat furrow, which indicates a doublure around the py- 

 gidium. If this pygidium actually belongs to C. spimdosus Angelin, 

 we shall be obliged to change its name, as it refers to a character 

 which does not belong to the species in question. From this descrip- 

 tion and the figures, the difference between the fwo closely allied 

 Scandinavian species appears clear enough." 



It may be as Gronwall states, that the pygidium illustrated by the 

 diagrammatic figure of Angelin does not belong with the cranidium 

 named C. spinulosus, but from our finding somewhat similar spines 

 on the border of the pygidium of C. bubaris it is not improbable that 

 Angelin was correct in placing the pygidium he found associated with 

 C. spinulosus under the same species. 



Formation and locality. — Middle Cambrian : Andrarum limestone 

 at Andrarum, Skane, Sweden. 



CORYNEXOCHUS STEPHENENSIS (Walcott) 



Plate 55, figs. 5, Sa-c 

 Menocephalus salteri ? Billings, Rominger, 1887, Proc. Acad. Nat. Sci., 



Philadelphia, Pt. i, p. 16, pi. i, fig. 6. (Described and figured.) 

 Karlia stephenensis Walcott, 1S89, Proc. U. S. Nat. Mus., Vol. 11, p. 445- 



(Described.) 

 Corynexochus roemingeri Matthew, 1899, Trans. Royal Soc. Canada, 2d 



sen, Vol. 5, Sec. 4, p. 47. (Calls attention to error in description of 



1889, and proposes specific name Corynexochus roemingeri for Dr. 



Rominger's specmiens. 

 Karlia stephenensis Walcott, 1908, Canadian Alpine Jour., Vol. i. No. 2, 



pi. 3, fig. 4. (Specimen figured.) 

 Karlia stephenensis Walcott, 1916, Smithsonian Misc. Coll., Vol. 64, No. 3, 



p. 224, pi. 2,^, fig. 8. (Described and figured.) 



The size of this species was erroneously stated by me in 1889. Dr. 

 Rominger's type specimen when being studied was placed in a tray 

 with specimens referred to Protypus, and the measurements assigned 

 to the species stephenensis were taken by error from Protypus hitch- 

 cocki which happened to be in the tray. 



I inserted an illustration of the type of the species stephenensis 

 alongside that of Karlia minor in my last paper on Cambrian trilo- 



