75 



The animal described and figured by Dr. J. Bigsby, 

 to which we have already referred, seems rather 

 different from our species. His specimens were 

 found at Montmorenci, near Quebec, (Canada) more 

 than an inch and a half in diameter. The following 

 are his remarks on this trilobite.* " The front of 

 the buckler is remarkably convex, and has on each 

 side near the base, three very small transverse lines, 

 scarcely to be called depressions, corresponding to 

 the sulci so strongly marked in the genus Calymene. 

 There is frequently, but not universally, a very minute 

 pisiform process on the centre of the front. The 

 whole upper edge of the buckler is always surround- 

 ed by a very ornamental semicircular border, some- 

 times semi-elliptical, of punctures placed in the 

 meshes of a net-work in high relief and arranged 

 close together, in rays, passing perpendicularly from 

 the buckler and forming at the same time when ob- 

 served transversely, curved lines parallel to its upper 

 rim or edge, excepting at the sides, where they di- 

 verge, leaving a space occupied by other lines of dot- 

 tings, parallel to the former, but speedily terminat- 

 ing on the cheeks of the buckler. The lines which 



tantummodo sex, rhachide angusta. Pygidium breve, rotun- 

 datum, Iffive ; adeo parvum ut ne quidem capitis disco respondeat. 



Obs. Oculos atque suturam facialem ex autopsia describere 

 licet. 



Vide Om. Palseaderna eller de sa kallade Trilobiterna af. 

 J. W. Dalman, pages 50 4. 



* See Geology of the Island of Montreal, in Lyceum of Nat. 

 History, N. Y. p. 214. 



