The long, dense fur of the Caribou holds so much moisture that when the animal emerges from swimming it endeavors to rid itself of the extra burden and cooling agency. This is effected to a large extent by a vigorous shaking of the body, head, and ears and a switching of the tail. The initial performance, lasting for perhaps a second or two, may be undertaken while the animal’s lower extremities are still in the water; and it is likely to be repeated from one to several times as it moves over the shore and ascends the adjacent ridge. The cloud of spray flying off is a sight to behold (fig. 9). The action is very much like that of a dog under similar circumstances. The fur may remain wet for a least 10 or 15 minutes after emergence from the water. In driving rain on September 5, I noticed an individual in a band of 20 Caribou shaking itself and sending the rain drops flying off in spray, just as when one emerges from the water. The Caribou also go through a very similar but perhaps still more strenuous performance for the obvious purpose of shaking off flies (perhaps primarily the warble flies, _Oedemagena_). On August 20 a buck passing along a ridge in the Barrens agitated the hide on its body several times with considerable vigor. A young animal (fawn or yearling) thus shook itself on August 28 as it approached the far side of Little River. I got the distinct impression that the hide was shaken horizontally in the case of moisture, but vertically in the case of insects; for the present, however, this is best considered as just an impression, and not a statement of fact. The muscles that agitate the skin of the sides should be particularly well developed through frequent practice with water and flies during the warmer part of the year. At the mouth of Little River, on August 30, I heard one of the Caribou in a large band “blow its nose,” so to speak, with vigor. The sound suggested that produced by a horse in vibrating its nostrils by forcefully expelling air through them. I suspect that the Caribou uses the same means, in an effort to fend off a nostril fly (_Cephenemyia_) bent on depositing its larvae. _Reference._--Harper, 1949: 230. _Signaling_ Apparently the commonest method employed by the Caribou for indicating or communicating suspicion or alarm is erecting the stub of a tail to a vertical position. This brings its white under side into full view, as the silent flashing of a danger signal to other Caribou. However, a solitary animal will exhibit signaling behavior as well as one in a band. The tail remains erect, whether the animal stands to stare uneasily at a suspicious object or flees from it in alarm. The action is common to old and young of both sexes. It is so characteristic of a fleeing animal as to give significance to the expression, “high-tailing it.” In normal, unalarmed progress the tail extends backward in a drooping curve (figs. 11, 12).