1066 NOTES ON AUSTRALIAN FOSSILS, 



The following are from Bowning, and were obtained by Mr. J. 

 Mitchell, who has presented a number of specimens to the 

 Australian Museum : — 



Proetus Ascanius, Cord. (?) 

 (Plate XV. figs. 1-4.) 



Barr. Syst. Sil. pi. 15, figs. 41 and 42. 



The specimens drawn are represented in Mr. Mitchell's collection 

 by one specimen about 11 mm. long, and another about 17 rum.,, 

 with other fragments of the same. 



The head presents a character which I find also in Proetus 

 ascanius represented in Barrande by the head only. While in all 

 the other species represented, the distance between the extremity of 

 the glabella and the front is small, and, at any rate, much shorter 

 than the length of the glabella itself ; in the above and in the 

 Australian species, this distance is exactly equal to the length of 

 the glabella. 



As to the pygidium, it resembles that of P. decorus, Barr. (pi. 17, 

 fig. 13) but differs from this only by having eight costaa on each 

 side of the axis instead of seven or less ; the axes are the same, and 

 I think it hardly possible to distinguish a detached pygidium of that 

 species from one of the Australian specimens. Fortunately two of 

 these are nearly complete, and in the absence of a complete figure 

 of P. ascanius, I must refer the species which has been obtained 

 from Bowning, provisionally to P. ascanius with a (?.) 



Barrande includes the last species in his "Etage F, Faune IV." 



Acidaspis Verneuili, Barr., 

 or 

 Acidaspis vesiculosa, Beyr. (?) 

 (Plate XV., figs. 5-14.) 



Barrande, Syst. Sil. Vol. I. pp. 710-715, pi. 38, figs. 1-6, 13-15 

 and 19. 



Represented by a head, (figs. 5 and 7), and pleurae separate. 



The pygidium, which would enable one to distinguish between 

 these two species, has not yet been found. 



