A New Lozver Cambrian Fauna. — Burr. 
45 
Olenellus (Mesonacisi asaphoides Emmons sp.* 
See Bull. U. S. G. S., No. 30, 1896, p. 168. 
Three small heads have been referred to this species. The 
presence of large individuals is known by fragments, particu- 
larly of the lateral cheeks. A few pleurae show the charac- 
teristics of this form, but these parts are not nearly so abun- 
dant as they are in the case of Holmia. 
The largest of the heads, although smaller, resembles close- 
ly the head of the specimen figured by Walcott (Loc. cit. PI. 
xc, fig. i). It shows the glabella complete with the whole of 
the left eyelobe. The glabella, at the anterior end of the 
eyelobes, has a diameter of 10 m m. The smallest of the 
heads has a maximum breadth of 15 m m. and a length of 
7.5 m m. The glabella has a length of 6 m m., a width of 4.3 
m m. in its widest part and of 3 m m. at its posterior end. 
This head differs from the young head figured by Walcott, 
(Loc. cit., PI. Ixxxviii, fig. id) in that it is wider between 
the eyelobes and bears a prominent tubercle upon the occipi- 
tal ring. It resembles the small head of Holmia referred to 
above. It lacks, however, the short spine which occurs just 
within the genal angles of the latter, and the glabella does 
not narrow toward its anterior end as in the case of Holmia. 
The reference of this to Olenellus asaphoides is provisional. 
The third head is considerably distorted, but shows in 
general the characteristics of the adult form of this species. 
It is intermediate in size between the other two. 
Olenellus sp. 
Three well-preserved heads of the Olenellus type have 
been found which have not. as yet, been identified with any 
known species. It is probable that these must be referred to 
a new species. It seems desirable, however, to give them 
further study. They will be described and illustrated in the 
paper by A. W. Grabau referred to above. 
*Since the above was in type, the material has been submitted to 
Mr. Charles D. Walcott. Mr. Walcott is of the opinion that the speci- 
mens which have been identified as Olenellus (Mesonacis) asajihoides 
and as Metado.xides magnificus are possibly to be referred tr> Olenellus 
(Holmia) broggeri. The identification of these species is, therefore, to 
be regarded as provisional. The writer wishes to ex]>ress his gratitude 
to Mr. Walcott for the opportunity of using the material in the U. S. 
Survey collections, and for many kind suggestions. 
