DESCRIPTION OF GENERA AND SPECIES. 149 



(second list of fossils), and fig. 10 (bed 12), p. 38], 2.5 miles (4 km.) southwest of Yen- 

 chuang, Sin-t'ai district, Shan-tung, China. 

 Collected by Eliot Blackwelder. 



Genus INOUYIA Walcott. 



Inouyia WALCOTT, 191 1, Smithsonian Misc. Coll., vol.57, No. 4, pp. 80-81. (Described and discussed 

 as a new genus essentially as below.) 



The species referred to this genus are represented only by the cranidium. This 

 in the genotype has a swollen, tumid frontal limb, small palpebral lobes, a convex 

 and more or less subrectangular glabella, strong dorsal furrows about the glabella. 

 and clearly marked glabellar furrows. 



Surface apparently smooth, but with a strong lens it has a slightly roughened 

 appearance caused by a shallow, irregular pitting. 



Genotype. Agraulos ? capax Walcott [1906, p. 580]. 



The swollen frontal limb, small palpebral lobes, and convex glabella at once 

 suggest Agraulos [see plate 15] and in fact all of the species now referred to Inouyia, 

 with the exception of I. titiana (Walcott) [plate 14, fig. 9], were at first referred to 

 Agraulos. My reasons for separating them and creating the genus Inouyia are that 

 the tumidity of the frontal limb is so pronounced as to become a marked feature and 

 the glabella is more rectangular in the typical species. To these should be added 

 the general effect of the cranidium [figs. 6, 6a], when compared directly with the 

 cranidium of Agraulos ceticephalus (Barrande) [plate 15, figs, i, ia]. I think it quite 

 probable that when entire specimens of the dorsal shield of the various species are 

 available for comparison other differences will be found to exist between Inouyia 

 and Agraulos. 



In grouping the species under Inouyia some are found to be close to Agraulos, 

 notably I. aborts (Walcott) [plate 14, fig. 16], I. ? acalle (Walcott) [plate 14, fig. 15], 

 I. ? regularis (Walcott) [plate 14, fig. 18], and it is probable that with more complete 

 specimens of the species they will be referred to a subgentis intermediate between 

 Inouyia and Agraulos. 



The wide fixed cheeks of Inouyia capax [figs. 1 1 , no] are confined to this species, 

 as all other species referred to Inouyia have relatively narrow fixed cheeks. The 

 large eye of /. f inflata (Walcott) and relatively narrow frontal limb serve to place 

 it apart from the other species. 



I am not at all satisfied with the arrangement of species under Inouyia, but in 

 dealing with such fragmentary specimens much must be left to future discovery and 

 closer work. 



Attention is also called to Ellipsocephalus hoffi Barrande [1852, plate 10, figs. 

 26, 27], as in that species the frontal limb is convex and the glabella subrectangular. 



The generic name is given in recognition of Dr. Kinos Ka Inouye, Director of 

 the Imperial Geological Survey of Japan. 



Inouyia abaris (Walcott). 

 Plate 14, Figure 16. 



Agraulos abaris WALCOTT, 1905, Proc. U. S. Nat. Mus., vol. xxix, p. 42. (Described and discussed as 

 a new species essentially as below.) 



Glabella and fixed cheeks convex, subrhomboidal in outline, and strongly 

 rounded in front. Glabella moderately convex; sides slightly converging; front 

 broadly rounded; surface marked by three short and very slightly impressed fur- 

 rows ; occipital furrow shallow and arching slightly forward at the center ; occipital 

 ring narrow at the sides, gradually increasing in width to the broad base of a 

 strong occipital spine. 



