

COMMON FINBACK WHALE. 183 



external side of the mouth, where they are longest. Toward the median line of the palate, 

 however, there are some four ranks of smaller, narrower plates so that the whole series forms 

 a gradual slope decreasing from the exterior to the median line of the mouth. The lingual 

 side of these triangular plates is fringed with long bristles that form a matted and tangled 

 mass, whereby the minute crustaceans on which the whale feeds, are strained out as by a sieve, 

 from the water taken into the mouth. Delage, who made a careful study of the arrange- 

 ment of the baleen plates, found the external row to consist of some 430 plates, then passing 

 toward the center of the mouth, came two ranks of shorter and smaller plates, each of about 

 the same number as the first. Then followed a fourth rank, consisting of twice as many plates 

 and finally a fifth rank, whose plates are smallest of all in size but from four to six times as 

 numerous as those of the first. 



The color of the plates and of their bristles is characteristic. The plates themselves are 

 generally particolored or streaked vertically. At their outer edge they are dark gray, or 

 purplish, varied internally with streaks of white, but toward the posterior end of the series 

 are more uniformly dark gray. On the right-hand side, a large number of the anterior plates 

 an- white, or white externally and more or less streaked with gray internally. As many as 

 half the total number of plates on the right side may be white, producing thus an extraordinary 

 asymmetry in color, for the plates of the left-hand side are dark throughout externally. The 

 coarse bristle-like fringe, as seen when looking into the mouth, is a dull white or yellowish white 

 ma-s, more or less curly and tangled. The longest blades of whalebone, exclusive of the bristles, 

 measure usually from 20 to 24 inches; the latter dimension is unusual, however, and is given 

 liy True (1904) for a very large specimen of 70 feet 8 inches, killed at Newfoundland. 



External Measurements. The total length of an adult Common Finback is usually about 

 iiO to 65 feet, and though Cocks has recorded one as long as 80 feet, it is not clear that he per- 

 sonally measured it or that the measurement was in a straight line from snout to caudal notch. 

 True (1904) has tabulated the lengths of twenty-five specimens measured by him at Newfound- 

 land. Of these the largest male was 65 feet long (19.81 meters), the largest female 70 feet 

 S inches (21.54 meters). The smallest of fifteen females found containing a foetus (and so sex- 

 ually mature) was 61 feet 10 inches (18.85 meters). Cocks, however, records a female of 55 

 t'eet 7 inches (16.94 meters) containing a foetus, and Millais a fifty-foot female also with a foetus. 

 Tliis last is probably near the minimum size of an adult. The data at hand do not warrant 

 the assumption that the females grow to a larger size than the males, though observations at 

 the Newfoundland and Norwegian stations show from two to four feet greater average length 

 for the females captured. 



The only available measurements of this whale based on a New England example are 

 those given by Dr. Thomas Dwight in volume 2 of the Society's Memoirs. These are incom- 

 plete, however, and in the following table I have given in addition to these the dimensions 



