Vol I. 



Stin — Cambrian Faunas of North China 



(iv) 39 



at the middle; occipital ring of medium width, curving slightly backward at the ends and 

 forward at the center, rounded on top; dorsal furrow strongly marked all about the gla- 

 bella and passing posterioi-ly into a narrow but well-defined furrow within the posterior 

 margin of the postero-lateral liml > ; the front of the glabella almost overhangs a strong 

 furrow witliin the frontal border, that separates the frontal border from the fixed cheeks; 

 frontal border or rim strong, rounded, and arching slightly upward in front of the 

 glabella. 



"Fixed cheeks a little more than one half the width of the glabella; they slope 

 gently back to tlje furrow on the postero-lateral limb and rather rapidly downward, in 

 front of the palpebral lobe, to the furrow within the frontal border; a clearly defined, 

 low, rounded palpebral ridge extends opposite the anterior fourth of the glabella to the 

 palpebral lobe, into the rim of which it merges ; postero-lateral limb about one and one-third 

 times as long as the widih of the glabella at its base, and back of the palpeljral lobe about 

 one third the length of the cephalon elevated at the outer rim, and rather narrow. The 

 facial sutures cut through the rounded frontal margin of the cephalon obliquely and 

 then extend around backward, passing almost directly to the anterior margin of the pal- 

 pebral lobe; curving around the rather small eye lobe, they pass obliquely outward and 

 backward, cutting the border of the head a little back of the postero-lateral angle". 



Tliis variety differs from the type species figured by Dr. Walcott in the shorter 

 glabella, narrow fixed clieeks, less distinct palpebral ridge, the more convex glabella, 

 comparatively broader frontal border, and also in the small size. This variety is partic- 

 ularly characterized by its small form with broad truncato-conicat glabella. 



var. minor B. blackwekleri 



iNTo. 529 No. 5P.0 



4.5 mm. 20.0 mm. 



.Measurements :- 



No. 528 

 Length of cranidium fi.5 mm. 



Width of cranidium at palpebral lobe 8.5 mm. 



5.5 mm. 

 3.2 mm. 



14.0 mm. 

 9.4 mm. 



Length of glabella 4.5 mm. 



Anterior width of the glabella 3.0 ram. 2.2 mm. 



Width of glabella at its base 4.5 mm. 3.0 mm. — 



Width of frontal rim LO mm. 0.8 mm. 3.0 mm. 



Width of occipital ring LO mm. 0.8 mm. 



Width of fixed cheeks on 



each side at the palpebral lobe 2.5 mm. 1.5 mm. — 



Horizon AND Locality:— Middle Canrbrian: from massive Changhia limestone 

 of Chao-Kou-Chuang, Luan-Hsien, Ohihli. Collected by University Excursion under my 

 direction (K. H. Hsii i^^M^ Coll.). 



