31 



and not so stout as that species. The proportion of depth to length about as 1 to 3f . Dorsal 

 fin opposite or arising sUghtly in advance of the anal fin. Enlarged, longitudinally striated 

 scales occur in a row on the back throughout its length on to the tail, and ventrally, behind and 

 in advance of the anal fin. The head bones are longitudinally and irregularly striated. The 

 anterior flank scales have generally two or three conspicuously, slightly oblique, longitudinal 

 ridges in the upper portion of their exposed surface, with about two less conspicuous ones beneath 

 them, having more the appearance of striations than ridges. These latter are parallel to the 

 lower scale margin and show a disposition to curve upward in front parallel to the anterior 

 margin. Posterior margin with four or five decided serrations. The posterior flank scales retain 

 the coarse ornamentation, with a reduction in the number of ridges and serrations. In these a 

 few fine istriations can be detected parallel to the lower margin. The lateral line is conspicuous 

 and appears to the unaided eye as a raised line traversing the length of the flank at mid-height. 



The generic position of this small form appears to the writer to be problematical. 



Ganobius modulus (Dawson). 

 Plate XI, figs. 1-7. 



Palceoniscus (Rhadinichthys) modulus, Dawson, 1877. Canadian Naturalist, new series, vol, 



VIII, p. 338, figs, a-d; and 1878, Acadian Geology, 3rd edition, supplement, p, 98, figs. 



18 a-d. 

 Palceoniscus modulus, Newberry, 1889. Palaeozoic Fishes of North America, Monographs U. S. 



Geol. Survey, vol. XVI, p. 187. 

 Rhadinichthys modulus, Smith Woodward, 1891. Gat. Fossil Fishes, British Museum, Part II, 



p. 466. 

 Rhadinichthys modulus, Eastman, 1908. Devonian Fishes of Iowa, Iowa Geol. Survey, vol. 



XVIII, p. 262, fig. 39. 



This species was first described by Sir William Dawson in 1878 (Canadian Naturalist), 

 from specimens obtained from Beliveau, N.B., and Horton, N.S. Three specimens from the 

 Peter Redpath museum, Montreal, have been examined by me. These are, the type collected 

 by Dr. Frank Adams at Behveau, plate XI, fig. 2, with a less perfectly preserved specimen on 

 the same piece of shale, and a third specimen, plate XI, fig. 3, from Horton, from which the figure 

 accompanying Dawson's description was evidently principally prepared. 



This fish is short and robust, the mandibular suspensorium is apparently nearly vertical, 

 the head is blunt in front, and a row of enlarged ridge scales passes backward from the occiput 

 to the dorsal fin, and occurs again in advance of the caudal fin. Similarly enlarged scales are 

 present in a single row along the belly. These characters suggest its being referable to Tra- 

 quair's genus Canoiius rather than to Rhadinichthys, to which genus it was assigned when first 

 described. 



