' POWRIE COLLECTION " OF FOSSILS 35 



dorsal spines of a fish which has been referred to the genus 

 Cestracion." From Scat Craig. 



Holoptyehius glg-anteus, Agassiz. Two scales from Scat Craig 

 figured by Agassiz, " Poiss. Foss. v. gres rouge," Atlas tab. 24, 

 Figs. 3 and 8. Duff's figure " Geol. Moray," Plate VII. Fig. 10, 

 is probably taken from the same specimen as Agassiz's Fig. 8. 



Dendrodus latus, Duff ( = D. biporcatus, Owen = Holoptyehius gigan- 

 teus, Ag.) Detached laniary tooth, with portion of internal 

 dentary bone attached, figured by P. Duff, op. tit., Plate VI. 

 Fig. 4; also by Agassiz, "Poiss. Foss. v. gres rouge," tab. 28, 

 Figs, i, 2. 



Dendrodus ineurvus, Duff ( = Holoptyehius nobilissimus, Ag.) A 

 mandibular internal dentary bone with laniary tooth attached, 

 figured by P. Duff in "Geol. Moray," Plate VI. Fig. n. 

 Figured also by Agassiz under the name of Cricodus ineurvus, 

 "Poiss. Foss. v. gres rouge," p. 88, tab. 28, Figs. 4 and 5. 

 Scat Craig. 



NOTE. Agassiz's genus Cricodus has been referred to the Rhizodont- 

 idse by myself 1 and by Mr. Smith Woodward 2 on account of 

 Pander's identification of it with his Polyplocodus, which 

 assuredly belongs to that family, and also because the 

 transverse section of a tooth figured by Agassiz as Cricodus 

 without specific name, "Poiss. Foss." vol. ii., part i., tab. 

 H, Figs, n, 12, is apparently of Rhizodont character. 

 But Agassiz in the text, ibid. p. 156, states that the 

 tooth from which this section was taken had its large pulp 

 cavity filled with a black matrix ; likewise that it was a frag- 

 ment broken at both ends, which "provenait d'une dent 

 enorme car il avait la grosseur d'un doigt." It is therefore 

 almost certain that this Rhizodont tooth, which he says is from 

 Scotland without naming any precise locality, is of carboniferous 

 age, especially seeing that a few pages further back (ibid. p. 

 105), he states that Cricodus occurs both in Devonian and in 

 carboniferous rocks. It is certainly very different from the 

 tooth figured by Duff as Dendrodus ineurvus, which Agassiz 

 afterwards refigured in his "Fossil Fishes of the Old Red Sand- 

 stone " as Cricodus ineurvus, and apparently adopted as the 

 type of the genus, seeing that he named no other species. For, 

 on examining this original specimen of ineurvus, I found, some- 

 what to my surprise, that it was in reality a Dendrodont or 

 Holoptychian tooth, apparently belonging to Owen's species D. 

 sigmoideus, and this I have long been convinced is synonymous 

 with Holoptyehius nobilissimus of Agassiz. The name Cricodus 



1 "Geol. Mag." (3) vol. v. 1888, p. 515. 

 2 " Catalogue of the Fossil Fishes in the British Museum," part ii. 1890. 



