The author acknowledges himself indebted to the laudable zeal of Mr. Scoreshy. jun. of Whitby, for the greatest part of the information which be here lays before the Society. Although the tusk of this animal is not uncommon, its skull has very rarely been brought into this country; and hence there has been little opportunity to correct the erroneous account given by travellers on this subject, who have generally maintained that the perfect narwhale has two of these tusks, although it is very common for one of them to be broken off. This opinion respecting the existence of two tusks has gained a more general belief in this country, from the exhibition of a stufied narwhale for many years in the Leverian Museum, but in which it is observed that the second tusk was artificially fastened in its
The fact, says the author, is, that there is never more than one tusk in the full-grown narwhale, and this is always in the left socket; but there is also observable, on the right side, another socket, in which it is presumed that the milk-tusk had been contained, and afterwards shed.
A further observation of Mr. Scoreshy’ on this ubject is, that the tusk of this animal is confined to the male, and consequently will not serve for a distinctive character of the species, as has hitherto been supposed.
A drawing of a female skull given to Sir Everard Home by Mr. Scoresby accompanies this communication. Simple inspection of this skull is represented by the author as sufficient to satisfy all doubts upon the subject, as there is no place provided for an adult tusk, although in all other respects it resembles that of the male, exce ting that the milk-tusk appears to have been placed on the left side instead of the right.
Along with the drawing of the female skull is a representation also of a male skull now in the Hunterian Collection: and upon comparison of them, it is observed that that of the female appears broader in proportion to its length than that of the male, for want of that prominence in the fore part that supports the tusk of the male, which, it is observed, was in this instance five feet long, although it is evident, from the state of the sutures, that the animal had not attained its full growth.
Many other instances are well known to naturalists, of tusks confined to the male of several species, as in the horse; but since the elephant is the only animal that can in bulk and proportional size of tusk be compared with the narwhale, and since the female elephant has tusks as well as the male, analogy had not suggested a doubt concerning the existence of them in the female narwhale; and hence the observation of a fact that could not otherwise have been ascertained become proportionally interesting.
