176 REPORTS ON THE STATE OF SCIENCE.—1912. 
in both species. The tip of the pectoral fin was the part most com- 
monly injured. Probably some blubber-eating fish may account for 
these abnormalities. ' 
In both species there was found to be a certain amount of variation 
in the shape of the dorsal fin, although its position was fairly constant. 
VIII. THroar Furrows. 
1. Balenoptera musculus (L.).—The number of the grooves counted 
between the insertion of the pectoral fing varies from 56 in No. 28 
(Table V.) to 86 in No. 49. It will be seen that there is no correlation 
between the number of furrows and the sex or size of the animal. The 
average number deduced from 19 observations is 73. 
The furrows extend from the tip of the mandible to the navel. From 
the level of the pectoral fins to the navel the furrows anastomose some- 
what irregularly. The ridges between the furrows are nearly always 
pure white in this species, but the dark blue-grey colour is often found 
in the furrows, being sometimes present to a greater extent on the left 
than on the right side. The size of the grooves ts fairly constant, being 
from 1 to 13 inch wide when unextended. The ridges are about the 
same width, 
Lillie ** suggests that the pink colour sometimes found in the throat 
grooves may be due to high vascularisation, and may thus help to aerate 
the blood. After an examination of several animals in which this pink 
colour occurred, I have come to the conclusion that the colour is cer- 
tainly due to blood, but I think it must be considered as a blood effusion 
occurring after the death of the animal. If it were an adaptation for 
securing a greater aeration of the blood, and so to allow the animal to 
remain under water longer than it otherwise could, we should expect it 
to occur much more often than it does. Also the pink colour, when it 
occurs, is generally only in patches. 
2. Balenoptera sibbaldii (Gray).—The throat-grooves in this species 
are arranged very much as in the common ‘ Finner.’ The number in 
the individuals examined varied from 70 to 78, and the average number 
was 73. A yellowish tinge sometimes occurs on the ridges, as men- 
tioned above under VI. 2. 
IX. WHALEBONE. 
1. Balenoptera musculus (L.).—The baleen of this species was 
fairly thick, with moderately fine bristles. The number of yellowish 
plates on the right side varies somewhat, as does also the width and 
number of dark longitudinal stripes which are found on these plates. 
The average number of plates along one side of the upper jaw 
was 383. 
The number of white plates in the front part of the right upper jaw 
varied from about 140 to 180. 
The average greatest length of a plate of whalebone, measured from 
the gum to the tip of the plate, was 1 foot 8 inches. 
The bristles were never black, but either dirty white or yellow. 
st Lillie, Proc. Zool. Soc., 1910, 2, p. 784. 
