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It will be observed that while in the young European specimens the proportional length of the whalebone falls below that of the American specimens, nevertheless, the largest Iceland whalebone equals or exceeds that of the largest American specimen. While the discrepancies above mentioned are not explainable at present, it appears that adult European and American specimens have whalebone of equal length.
Although the largest whalebone cited in the preceding table is only 7 ft. 4 in. long, various writers on the Colonial Right whale fishery mention lengths for this species of 8 feet and 9 feet. This might be regarded an exaggeration, but there are slabs of whalebone from the Pacific Right whale in the National Museum which measure 8 ft. 2 in. and 8 ft. 6 in., respectively, and the whalebone of the Atlantic species may have formerly reached that length in some cases.
The Atlantic Right whale known to American whalers was called by them the Black whale, in allusion to its color. In the European Norilcaper the body in all recorded cases was black. The young San Sebastian whale, judged by the copy of Monedero's drawing given by Graells (52, pl. 1, fig. 2) appears to have been uniform black. The Taranto whale, according to Gasco (47, 14), was also uniform black, as was Segnette's specimen of 1680. Regarding the Iceland whales, Guld. berg remarks as follows (59, 16):
“The color of the skin is, as already known, deep black, sometimes with a tinge of blue (einem Stich ins Blaue). This deep black color is spread over the whole body. On this account, I was surprised that Capt. Larsen remarked that the young example canght by him was of a lighter color on the belly. This statement was, however, in part at least confirmed by the fragments of skin sent me, as many of these showed white epidermis layers (Oberhautpartien), which were sharply contrasted from the black dermis layers (llautpartien) on the same pieces. In the pieces of skin preserved in alcohol, the unpigmented epidermis layers were yellowish-white, and the boundaries very sharply defined from the deep black pigmented parts. By inquiry among the sailors and others, who had seen the freshly caught Nordcaper, as well as by direct communication by letter with Capt. Berg, it was, however, established that only single white spots appeared here and there on the otherwise black body. The white spots were found on the extreme tip and surface of the pectorals, on the tip of the flukes as well as in the 'bonnet' on the snout,-all places infested by parasites. The spots are small and can hardly be found in all examples.
“In the specimen figured (59, pl. 1), judging from the photograph, white spots appear to occur around the genitals, but I can not affirm this with certainty.
The foregoing statements seem to confirm the idea that the European Nordcaper is normally black throughout. The white spots appear to be due to the alteration of the skin produced by parasitic cirripeds, as in the Humpback. The yellowish-white spots in the alcoholic specimens of skin might be attributed to a separation of the epidermis, and accumulation of air or alcohol below.
Among the American specimens, we find that the Charleston whale was entirely black. The Egg Harbor, New Jersey, whale was also black.
The Cape Lookout specimen, captured March 20, 1894, a female, was said to be a “white-bellied” one. The figure published in the Bulletin of the North Carolina Dept. of Agriculture (14, No. 7, April, 1894, p. 4) shows the whole under surface light colored, from a point in advance of the eye to the anus, the white area extending up to the base of the pectorals and having irregular margins. If the drawing was correctly made from the specimen itself, it indicates a remarkable color variation. In a letter Mr. H. II. Brimley remarks that this specimen had “ a great deal of pure white on its under side.”
The foregoing facts may be summed up as follows:
Three specimens of the European Nordcaper are recorded as being entirely black, and the Iceland specimens were also black, with the exception of one young one, which was reported to be lighter colored on the belly. Of three American specimens, two are recorded as entirely black, and one (adult female) as having “a great deal of pure white on its under side.” (See pl. 46, figs. 1 and 2.)
OSTEOLOGICAL CHARACTERS-NUMBER OF VERTEBRÆ.
The skeleton of the European Nordcaper has been described in detail and figured by Gasco (47 and 48), Graells (52), Capellini (13), and Guldberg (59). The skeleton of American specimens has been described and illustrated by Holder (61) and Manigault (68). (See pls. 42-46.)
The number of vertebræ has been given by these authors for several individuals, as follows:
'Gasco gives 13 pairs of ribs, but thinks there may have been 14 pairs. Hence, the formula was perhaps 7, 14, 12 (or 11), 23 (or 24) = 56.
?U. S. National Museum, No. 23077, 'Amer. Mus. Nat. History. • Holder states that the total is "probably 57." * Possibly only 10 lumbars. Type of B. cisarctica. "Mus. Comp. Zoology. 'Field Col. Mus., Chicago.
It will be observed from these tables that the number of dorsals in both European and American specimens is uniformly 14, the only exception being in the San Sebastian (Spain) skeleton. In this case, however, Gasco thinks there may have been 14 pairs of ribs.
The number of lumbars is fixed by the position of the first chevron. As the series of chevrous is commonly incomplete in museum specimens, and, furthermore, as the transition from the quite sharp inferior carina of the lumbar vertebræ to the paired inferior ridges of the caudals is not always abrupt, it is extremely difficult in many cases to determine correctly the number of lumbars. The widening of the posterior end of the inferior carina may be more or less distinctly marked on the 32d vertebra, in which case there might be considered to be 10 lumbars. On the other hand, this thickening of the carina may not be pronounced until the 34th vertebra is reached, in which case, 12 lumbars might be counted.
My own observations on American specimens lead me to believe that 11 lum. bars may be regarded as the normal number, varying from 10 to 12. Guldberg and Gasco, however, regard 12 lumbars as the normal number for European specimens.
The Guetaria (Spain) skeleton of 1878 appears from Graells's figure (52, pl. 3) to have but 8 lumbar vertebræ and about 26 caudals. I am unable to account for this discrepancy and Prof. Rios y Rial's description (52, 65–67) is unintelligible to me on account of the manner in which he divides the vertebral column.
It would be possible to reduce the number of lumbar vertebræ to 8 in the Long Island (N. Y.) skeleton in the National Museum, No. 23077, if the first caudal were regarded as that in which a thickening of the posterior end of the inferior median carina first occurs. It is obvious that the question of the real number of lumbars in the species cannot be authoritatively settled until the chevron bones are examined in situ in a number of adult and fætal specimens. Gervais's views regarding the number of lumbars in the Sulphurbottom whale are of interest in this connection. (See p. 182.)
The best figures of the skull of the European Nordcaper are those of Gasco (47, pls. 2-4) and Graells (52, pls. 3-4). While these agree in most particulars, they show a considerable divergence at certain points. The most striking difference is in the direction of the orbital processes of the frontal. In Gasco's figure these processes lie entirely behind the line of the antero-superior end of the occipital, and are directed backward, while in Graells's figure the greater part of the frontal processes lies in front of the line of the occipital, and the processes are directed forward. This relation of the bones is shown especially in 52, pl. 4, fig. 2, but also in pl. 4, fig. 1, and in pl. 3, fig. 2. In the latter, which is a figure of the entire skeleton, the skull appears to be a reduced copy of pl. 4, fig. 2. In pl. 3, fig. 1, which is a view of the entire skeleton from the side, the orbital process of the frontal is represented more as if directed backward rather than forward, thus
agreeing better with Gasco's figures. Another important difference in Graells's figures, as compared with those of Gasco, is that the anterior ends of the premaxillæ are represented as narrow and acuminate. Graells's figures are reproductions of drawings by Sr. Janer, while in Gasco's figures the outlines are taken from photographs, “to avoid inexactness.” This latter may, therefore, be considered the more reliable.
Gasco's figures (47, pl. 2, figs. 1 and 2 ; pl. 3, fig. 1) of the Taranto (Italy) whale show a very close agreement with the skull of the specimen from Long Island (New York) in the National Museum, No. 23077, pls. 42 and 43. The figures of the under surface of the skull especially (allowance being made for the slightly different point of view) show a very complete agreement. No one on comparing these several figures can, I think, fail to be convinced that they represent one and the same species. This is a matter of great importance, because, as will be pointed out presently, the measurements of the American and the European skulls vary considerably among themselves. The causes of this variation will be considered later.
I personally compared the skull of the Long Island (N. Y.) specimen in the American Museum of Natural History, New York, with photographs of the Long Island skull in the National Museum, No. 23077, and was unable to discover any differences of importance. In Holder's figure of the former (61, pl. 12) the superior outline of the rostrum does not descend rapidly enough anteriorly, due perhaps to the intermaxillæ not being represented as thick at the middle as they really are. In most other respects the figure is a good representation of the skull.
In one character Gasco's figure of the Taranto (Italy) skull differs from the American skulls I have examined. The premaxilla extend so far back as to pre. vent the union of the maxillæ with the median anterior prolongation of the frontal at the vertex. In the American skulls in the Washington, Philadelphia, and Raleigh museums the premaxillie are shorter posteriorly and the maxillæ project inward toward the median line along the sides of the nasal process of the frontal. This may, I think, be regarded rather as an individual variation than as a character of specific importance. In Graells's figure (52, pl. 4, fig. 2) the relation of the parts, as represented, agrees with the American skulls above mentioned.
The general shape of the nasals in the Taranto (Italy) and Guetaria (Spain) skulls is the same as in the Long Island (N. Y.) skull in the National Museum,
No. 23077, except that there is a difference in proportions in the case of the Taranto specimen, as represented in Gasco's figure (47, pl. 4, fig. 9). Indeed, the nasals appear to differ in proportions in all the specimens, no two being exactly alike. In the type of B.cisarctica the nasals have the same emargination of the distal free border as in other American and European specimens, as shown in text fig. 84. The convex exterior border is in part overlaid by the intermaxilla when the nasal is in position,
so that the latter then appears rectilinear in outline, as in other specimens. The variation in length and breadth in the different specimens is in part due to the unequal development of the median portion of the frontal against which the nasals rest.
The proportions of the various American and European skulls are indicated by the measurements given in the following table:
From “hind angle," i, e., base of rostrum; hence smaller. ? From figure.
3 Least, from figure. * On comparing Gasco's figures it will be seen that the rostrum in the top view is much too short. Straight. * Total length given only approximately by Capellini ; hence taken from Gasco, 2.27 m. 7 " From point of meeting of internal lateral margin with inferior margin of the condyle"; hence, a smaller per cent. 8 Caudals spaced too much, . From Manigault.
11 Twice 12.