712 SILURIAN TRILOlilTES, 



Tliis is the largest Odontopleurid yet discovered, and seems to 

 a-'ree in size with C. Verneuili, its European analogue. When 

 mature it appears to have been from four to five inches long. 



AVe have had the advantage of studying the specimens pro- 

 visionally referred by Mr. Hatte* to Acidaspis Frevosti, Barr. 

 One of these (his fig. 11) we believe to be the present species, 

 although Mr. Ratte represented spines along the frontal borders 

 of the cephalon which do not exist in the specimen, whilst he 

 ne^dected to figure the genal and occipital spines that are preserved. 

 This specimen also shows the subpedunculate protruding charac- 

 ter of the eyes. 



Named in honour of our valued correspondent, Capt. Anthony 

 W. Vogdes, U.8. Artillery, San Francisco, author of the highly 

 useful " Bibliography of the Palajozoic Ci'ustacea." 



Loc. and Horizon. — Bowning Creek, Bowning, and Limestone 

 Creek, near Bowning, Co. Harden, Lower Trilobite Bed— Bowning 

 Series ( = Hume Beds, Jenkins, and Yass Beds, David)- 1 Wenlock. 

 Coll. — Mitchell; Austi-alian Museum, Sydney; Geological Survey 

 of N.S Wales, Sydney. 



Ceratocephala Jackii, Sji.nOV. 



(PI. LIIL, fig. 8, PL L. fig. G.) 



Sp. C}iar. — Cephalic shield or cephalon — Greatest width a little 

 more than twice the length (16-7), subelliptical, very moderately 

 tumid, and distinctly granulated. Glabella large, length frOm centre 

 of the neck furrow equals the greatest width between the axial 

 furrows; central lobe moderately tumid, and arched very gradually, 

 sloping to the front margin and into the neck furrow, front angles 

 slightly expanded; median and basal pairs of glabella lobes dis- 

 tinct, moderately tumid; glabella furrows wide and shallow; false 

 furrows and also the axial furrows wide and shallow, the latter 

 being much less distinct than the former. Fixed cheeks 

 moderately large; genal lobes large, clearer-shaped, granulated, 



* Pioc. Linn. Soc. N.S. Wales, 1SS6, I. (2), Pt. 4, t. 15, f. 11 and 12. 



