180 Proceedings of tJte Royal Society oj Victoria. 



Thorax of fourteen segments ; axis narrower than the pleura ; 

 well raised. The pleural grooves reach to the end of the pleura. 

 Surface not granulate. 



Pygidium short, narrow ; very indistinctly separated from the 

 thorax. Axis tapering uniformly backward from the thoracic 

 portion of the axis. Margin smooth and semicircular, but the 

 margin is notched by faint grooves. 



Distribution. — Silurian : South Yarra, Melbourne. 



Affiiiities. — This trilobite is a Cyphaspsis, and specifically its 

 most marked character is the presence of the anterior median 

 spine. Ethericlge Jun. and Mitchell^ have described several 

 species of this genus from New South Wales, from all of wldch 

 C. spryi differs in the abseiice of the anterior spine. Its nearest 

 Australian ally is C. l>ozv?iiHge?isis, Mitch.,- which it resembles by 



1 R. Etheridge Jun. and J. Mitcliell. Tlie Silurian Trilobites of New South Wales. Proc. 

 Linn. See. N.S.W., ser. 2, vol. viii. (1894), pp. 170-172, pi. vi., fig. 3, pi. vii., fig. 3i-k. 



'i 3. Mitchell. On some new Trilobites from Bowning, Proc. Linn. See, N.S.W., new 

 ser. vol. ii. (1S87), p. 438, pi. xvi., fig. 3. 



