338 EXPLANATION OF PLATE. 



Mr. Barkas's two names must therefore fall into the rank of 

 synonyms.* 



Glimaxodus imbricatus is somewhat intermediate between the 

 Magnesian-Limestone species and that from the Coal-Measnres. 

 The crown is narrower and more elongated than it is in C. lin- 

 gucBformis, and the ridges are more delicate, thus approximating 

 to Janassa hitimiinosa. The anterior cutting-margin seems to 

 have been deep ; but the extreme border is wanting in M'Coy's 

 figm'e : the root is also deficient. In the description in the 

 "British Palseozoic Fossils" the posterior extremity is mistaken 

 for the anterior, 



Mr. Howse will shortly publish in the *' Annals of Natural 

 History" a full description of the oral annature of Janassa hitu- 

 minosa in continuation of this paper. It therefore only remains 

 for us to state that the species will stand thus : — 



Janassa, 1832, Miinster. 



CUmaxodus^ 1848, M'Coy. 



J. hituminosa, 1820, Schloth., sp. 



J, imbricata, 1848, M'Coy, sp. 



if. linguaformis, 1868, Atthey, sp. 



EXPLANATION OF PLATE. 

 PLATE IX, 



Fig, 1, Two rows of teeth of Janassa (C.) linguaeformis, a little over the 

 natural size, arranged in order, the anterior row merely indi- 

 cated : «, central primary tooth ; h, root ; c, first lateral primary 



* C. vermiformis was not described till 18G9. Mr. Atthey's description of C. linguxformis 

 aud that by Mr. Barkas of C. matus appeared simultaneously on the 1st of November, 1868: 

 the first in the "Annals of Natural History," the second in the "Geological Magazine." 

 Mr. Atthey's paper, hovrever, was read at the meeting of the " Tyneside Naturalists' Field 

 Club" on the previous 9th of October (see "Nat. Hist. Trana. of Northumberland and Dur- 

 ham," Vol. III., p. 295), so that the priority of C. lingvxformis is clearly established. And 

 moreover Mr. Atthey's specimens had been in his cabinet for many years, and were seen, or 

 might have been seen, by all the pateontologists of the district. Mr. Barkas, indeed, says 

 that he named and described C. matus in a lecture delivered by him, on the 2Sth of Septem- 

 ber, to the Mechanics' Institution of Newcastle-upon-Tyne. But even were this stilctly 

 correct we apprehend it would be no such publication of the species as to secure priority. 

 Where, however, is the record either naming or describing at this time C. ovatus? We have 

 searched for it in vain. 



