BY JOHN MITCHELL. 539 



their cheeks coalesced are placed with other species in which the facial sutures 

 are present. The same practice occurs in the case of the genus Ceratocephala, 

 and to overcome the difficulties surrounding the classification of the species, I 

 might have accepted these cases as precedents and referred it to Brachymetopus 

 Tentatively. 



However, it has been suggested to me by General A. W. Vogdes, of San 

 Diego, Cal., U.S.A., an undoubted authority on trilobites, that a fitting resting 

 place for the one under discussion might be in the genus Cordania J. M. Clarke, 

 and, after a careful study of the genus I am persuaded to place it therein. 

 Cordania was proposed by J. M. Clarke in 1892, for the reception of four species 

 of Phaethonides described by Herrick (Bull. Denison Univ., 4, 1889, pp. 56-59). 

 Since then, five other species have been added. All of the species are from the 

 United States, and all, except Cordania (Phaethonides) occidentalis Herrick, 

 from rocks of Devonian age. The exception is from the Carboniferous of the 

 Waverley Group of Ohio, U.S.A. The pygidium of this species closely resembles 

 the pygidium of the local form : the numbers of the segments in the axis and 

 pleurae of each are nearly the same, and the ornamentation and general contour 

 of the two are similar; but they differ much in their head-shields, and in size, 

 the Australian one being mucji the larger. The pygidium of Cordania {Phae- 

 thonides) spinosus Herr. (I.e.), from the Devonian of the Waverley gToup of 

 Licking County, Ohio, U.S.A., has a still greater resemblance to that of our 

 specimens. The contour in each is similar — in the axis of the former there are 

 fourteen ring's and nine pairs of pleurae in the side lobes, in the latter these 

 parts are fourteen or fifteen and nine or ten respectively; the spinate tubercles 

 are more numerous on these same parts of the latter than they are on those of 

 the former, though they are similar in character. The head-shields of the two 

 are dissimilar in several respects, and the local one is of larger dimensions. In 

 a general way the Australian form resembles C. gasepiou Clarke. 



The genus Cordania, up to now, was confined to the United States, and the 

 discovery of it in Australian rocks will prove to be of interest. Though in the 

 United States the genus is almost exclusively Devonian, I am, because of the 

 general aspect of the associated fossils, disposed to place the geological age of 

 the Australian specimen as Carboniferous. 



My sincere thanks are tendered to General A. W. Vogdes, of San Diego, 

 for ample notes and suggestions which were of much assistance to me in deter- 

 mining the generic position of the trilobite here described. To Mr. Legge, of 

 Legge's Camp, Myall Lakes, I wish to express my indebtedness for help which 

 facilitated the work of collecting from this new locality. The species is de- 

 dicated to Master Frank Gardner who was the fii'st to bring specimens of it 

 under my notice, and who, though only thirteen years of age, is a keen student 

 of geology. 



Loc. and horizon. — Brambles farm,. Myall Lakes, Parish of Eurenderee, 

 County Gloucester, N.S. Wales, associated with Aviculopeeten, Spirifera, Conu- 

 laria, and one or two species of Prodnctus, etc. Carboniferous (!) ; but not the 

 equivalent, it seems to me. of any group of rocks of that age that has hitherto 

 come under my observation in this State. 



Pttchoparia herrotskii, n.sp. (PI. liv., figs. 11, 12.) 

 (For a previous reference to this trilobite see BuU. N. Terr., Dec, 1915.) 



Descn>«Jo«.— Complete form oval. Head-shield of medium leng-th, semi- 

 circular, smooth. Glabella short, narrow, subeonical, mildly convex, sparsely and 

 faintly tuberculate, anterior pair of fun-ows faint, median and basal pairs fairly 



