382 



Olenellus ( ?), sp. 



PI. xxxix., fig. 1. 



Olenellus, sp., Etheridge: Trans. Roy. Soc. S. Austr., xxix. r 

 1905, p. 247, pi. xxv., fig. 1. 



Obs. — At present I am unable to refer this imperfect 

 portion of a cephalon to any definite genus. The published 

 figure does not convey a correct idea of the anterior outline, 

 but represents the specimen terminating at the anterior 

 margin of the glabella, whereas there is, in reality, portion of 

 a wide concave area, anterior to the glabella, as in many 

 other Trilobites; this alters the whole aspect of the specimen. 

 There are but two pairs of furrows, instead of three, as I said 

 in my former description, the basal pair complete and ex- 

 tending across the glabella, and an anterior pair very faintly 

 marked, mere "nicks," in the axial furrows. 



This imperfect glabella may be, as suggested by Mr. F. 

 Chapman, an example of his Ptychoparia thielei, but before 

 adopting this suggestion I prefer to await additional and more 

 perfect material. 



Loc. — Neighbourhood of Wirrialpa, Flinders Range,. 

 South Australia (Howchin). 



Hor. — Cambrian (Etheridge). 



Genus Ptychoparia, Corda, 1847 

 (Prod. Mon. bohm. Trilobiten, 1847, p. 25). 



Ptychoparia ( ?) tatei, H. Woodward. 

 PI. xxxix., figs. 2 and 3. 



Dolichometopus tatei, H. Woodward: Geol. Mag., i. (3), 1884, 

 p. 344, pi. xi., fig. 3. 



Olenellus pritchardi. Tate : Trans. Rov. Soc. S. Austr., xv., 

 pt. 2, 1892, p. 187, pi. ii., fig. 12. 



Bedlichia tatei, Walcot't : Smithsonian Miscel. Collns., 64, 

 No. 5, 1916, p. 539. 



Sp. Chars. — Cephalon very minute, in all probability 

 semicircular ; glabella oblong and narrow, very slightly 

 conical, arched, and apparently unfurrowed ; axial furrows 

 deeply impressed laterally, but interrupted at the distal end 

 of the glabella by a low bridge, which crosses the anterior area 

 to the cephalon-limb border, the area concave, and both it 

 and the border wide. Fixed cheeks somewhat cornute in out- 

 line; ocular ridges, or "eye-lines" describing a wide obtuse 

 curve, broad and prominent ; neck ring lobate, deep ; free 

 cheeks unknown. 



Obs. — The two first records of the above synonymy are 

 founded on the study of four specimens : firstly, a replica of 

 Dr. H. Woodward's Dolichometopus tatei, very kindly sup- 

 plied by Dr. Smith Woodward; and secondly, Tate's three 





