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those of the anterior flank scales. The posterior margin is serrated. The four nearest the fin 

 are well preserved in the specimen shown by Jackson in figure 1 of his second plate; of these one 

 is shown in plate V, figure 4. As in the flank scales, a more posterior position leads to a replace- 

 ment of the strife by punctations, and an increasing area of smooth surface, in a variable degree in 

 different specimens. The enlarged scales between the dorsal fin and the tail are similar in shape 

 and ornamentation to those immediately preceding the dorsal fin, gradually decreasing in breadth 

 and becoming more pointed behind, as well as more angularly convex transversely as they 

 approach the tail, on the upper lobe of which they are continued in diminishing size to its upper 

 extremity. An emargination of the overlapped anterior surface, present in the ridge scales 

 preceding the dorsal fin, becomes more pronounced in those behind this fin, and especially so in 

 those on the upper lobe of the caudal fin, which are V shaped. In these last the overlapped 

 surface is much increased, and extends back to near the posterior end of the scale as a smooth, 

 narrow, depressed area in which the preceding scale closely fits. There are three or four enlarged 

 imbricating scales in a row between the anal fin and the lower lobe of the tail, and the same 

 number between the former and the pelvic fins. These scales, in ornamentation and general 

 shape, are similar to those of the dorsal ridge near the dorsal fin. In advance of the ventral fins 

 enlarged scales are also present, with sculpture like that of the more anterior dorsal scales, but, as 

 already mentioned, their exact disposition has not been ascertained, as none of the specimens 

 seen provides sufficiently definite information in this respect. The lateral line scales on the flank 

 extend in a row from near the head above the mid-height of the body backward toward the tail 

 midway between the upper and lower surface of the caudal pedicle. Each of these scales is 

 pierced by a small passage whose external opening has the form of a minute crescentic slit round 

 which the surface of the scale is slightly tumid. In most of the specimens these scales are 

 proportionately higher than those of the rows immediately above and below. In none of the 

 specimens examined have the minute openings been traced as far as the tail. 



Elonichthys brovmi (Jackson), from the Albert shales, differs from any known species of the 

 genus. Its scale ornamentation resembles in a general way some of the species so admirably 

 described and portrayed by Dr. Ramsay H. Traquair in his monograph on the Palseoniscidse, 

 in Vols. XXXI and LV of the Palseontographical Society of London; but differences in the 

 general proportions of the body, in the proportions and relative size of the fins, in the exact 

 style of sculpture of the scales and fin rays, as well as in other particulars, mark this Albert 

 shales fish as a distinct species. 



The type specimen of Dawson's Paloeoniscus jacksoni (figured by Jackson in figure 4 of his 

 first plate) is not available for study, but, judging from the figure, and from Dr. Jackson's re- 

 marks on its scale ornamentation, it appears to the writer probable that it is not distinct from 

 E. brovmi. A specimen from McGill University museum, labelled P jacksoni, Hillsborough, 

 No. 2698, now before me, has the scale sculpture and the ornamentation of the joints of the fin 

 rays such as are seen in Jackson's type (plate I, figure 2) with which it is evidently conspecific. 

 Among the specimens from the Natural History Society of New Brunswick is the original of the 

 one from which the plaster cast mentioned by Sir William Dawson in his "Acadian Geology" 

 was taken, which cast formed part of the material on which P. jacksoni was based. The 

 specimen consists of the posterior part of the fish, from slightly in advance of the dorsal fin 



