-~T 
THE WHALEBONE WHALES OF THE WESTERN NORTH ATLANTIC. 17 
NAVEL AND MAMMARY SLITS. 
The navel in the Newfoundland Sulphurbottoms is a more or less elongated 
scar, usually about 8 in. long, surrounded by the abdominal ridges and furrows, 
which are somewhat displaced and bent outward by it and usually extend some- 
what beyond it. (Pl. 17, figs. 1 and 2; pl. 18, figs. 3 and 4; pl. 19, fig. 2.) 
The mamme of the female are contained in longitudinal slits situated a little 
above the median line and opposite the end of the clitoris. Above and below 
these slits, or, in other words, nearer to and farther from the median line, are one or 
several furrows which are parallel with the slits. The largest of these furrows is 
commonly longer than the mammary slit and very deep. (See pl. 20, figs. 1 and 
2.) In No. 8, 61 feet long, the mammary slits were 15 inches long. 
The mammary slits and other parts surrounding the sexual orifice do not cause 
any marked convexity of the inferior outline of the body, but there is a slight de- 
pression posteriorly which marks the position of the anus. (See pl. 19, fig. 3.) 
The male Sulphurbottom has rudimentary mammz of considerable size con- 
cealed in slits like those of the female. (PI. 20, figs. 3 and 4.) These slits are 
situated about midway between the anus and penis orifice, and are unaccompanied 
by parallel furrows. In No. 2 (length 71 feet), the left slit was 16 inches long 
and the right 19 inches. The orifice of the sheath of the penis in No. 15 (length 
63 ft. 6 in.) was 3 feet long. The penis itself in No. 2 (length 71 feet) was 6 
feet long on the curve; circumference of the glans at the base, 2 feet. Testicle 
in No. 13 (length 65 ft. 11 in.), 27 inches long, 10 inches broad. 
FLUKES. 
The flukes were invariably cut off the Newfoundland Sulphurbottoms before 
towing them in and I did not have an opportunity to see them in the adult. Ina 
feetus 12 feet long they had the form characteristic in the genus, convex anteriorly, 
slightly concave posteriorly, with moderately recurved tips, and a central notch. 
In No. 6, 2, 65 feet long, the depth of the flukes from the notch to the line of the 
anterior base, or insertion, was 3 ft. 6 in.; in No. 11, 4, length 71 ft. 6 in., the 
depth of the flukes at the same place was 3 ft. 8 in.; in No. 14, 2, length 77 ft. 
2 in., the depth of flukes was 4 ft. 9} in. The depth of the notch in this individual 
was 9 inches. It was very obtuse. 
WHALEBONE, 
The whalebone in the Newfoundland Sulphurbottoms (pl. 15, figs. 1 and 2; 
pl. 16, figs. 3 and 4) is thick and black throughout, including the bristles, as in the 
European specimens. In eleven specimens from the former locality, its length 
above the gum (without the bristles) was as follows : 
