Largest Austyalian Trilobite JiitJierto discovered. 193 



an apical break in the outline of its tail, , although it is not 

 unknown in the genus Lichas. These points certainly weigh 

 against the reference of Mr. Sweet's fossil to Bronteiis, but it is a 

 matter for consideration, whether or no they are outweighed by 

 those points that may be considered in favour of such a 

 reference. The largest Broiiteics of which I have any record is 

 B. LaJ>ha?ni, Whitf,* with a tail measuring four inches broad, by 

 four and a half long ; and the next is B. viator, Barr., a tail of 

 which, figured by Novakf, measures three and a quarter inches 

 in length by three and a half in width. The largest described 

 Australian Bronteus in B. /etiki7isi, E. and M.,| but even this, 

 compared to the present form, is a mere pigmy. 



From the point of size merely, this pygidium must represent a 

 Trilobite well-fitted to hold its own amongst some of the largest 

 known. For instance, taking for comparison our hitherto 

 largest Australian Bronteus, B. Jenkinsi, we find that a pygidium 

 possessing a length of one and a half inches represents an entire 

 body of nearly thi-ee and a half inches. The length of our 

 present specimen, allowing for distortion, is five inches, therefore, 

 in the same degree of proportion, the full body would be as near 

 as possible a foot long. 



Turning to the existing record of large Trilobites we find that 

 the Paradoxides Tessini, Linn.§, is twelve inches in length, the 

 almost equally large P. Forclianinieri, Angelin||, is ten inches in 

 length, whilst the immense Asaphiis (Megnlaspis) Jkeros, Dalmanll, 

 is fourteen inches long. Mr. F. Bayan estimates that the total 

 length of Lichas Heberti, judging by the size of the cephalic 

 shield, must have been, in round numbers, between two feet and 

 two feet six inches long**. Many other instances might be cited, 

 including the British Paradoxides Davidis, Salterff, which is 

 thirteen inches in length ; and the American Dalmanites 

 (Coro)mra) itiymecophoriis, Green, figured by Hall and Clarke J J, 



-■ Geol. Wisconsin Survey, 1873-79, 1882, iv., p. 31u, t. 22, f. 3. 

 t Beitriige Pal. Ost.-Ungarns, Heft. 1 and 2, 1883, t.ll, f.l6. 

 I Proo. Linn. Soc. N.S. Wales, 1890, v. (2), p. 502, t. 18. 

 § Angelin and Lindstrom, Pal. Scandiuavica, Pt. 1, 1878, t. 1 

 , 11 Angelin and Lindstrom, PaL Scandinavica, Pt. 1, 1878, t. 2. ' 



^ Angelin and Lindstrom, Pal. Scandinavica, Pt. 1, 1878, t. 3. 

 »« Bull. Soc. Geol. France. 

 tt Brit. Organic Remains, Dec. xi., 18 , t. 10. 

 XX Pal. New York, 1888, vii., t. 15. 



