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Show 1868.] MR. R. BROWN ON THE SEALS OF GREENLAND. 407 the group. For the reasons already stated, I have purposely omitted giving any craniological or other osteological distinctions, except in a few isolated cases, limiting what descriptive remarks I may have to make to some disputed points regarding the very fallacious distinctive marks derived from the skin. As in the previous paper, I have not attempted anything like a complete history of their habits, geographical distribution, &c, chiefly limiting my remarks to what has fallen within m y own observation or knowledge. I have occasionally mentioned facts already known, but still requiring further confirmation ; but in general, when I can add nothing to the remarks of other naturalists, a reference is made to their writings, such references being intended to convey the imputation that our observations are similar in their nature. The list of popular names attached to each species is the result of not a little work and extensive acquaintance among the seal-hunters and fishermen of the northern coasts. The scientific synonyms are only given when no doubt existed of their applicability, and are not intended to be a complete list. 2. Physiological Remarks on the Habits of Seals. The Seal is, to a considerable extent, fitted for terrestrial progression, which it perforins chiefly by the muscles of the trunk, aided bv those of the extremities. The result is a rolling, waddling, or shuffling kind of motion-the animal leaning over on one anterior extremity, and then rolling back on the other to make a similar use of it, using them thus alternately and the muscles of the spine continuously, chiefly those of the lumbar region and erectores spince. In carnivorous animals the intestinal canal is shorter than in graminivorous species : yet there are exceptions ; for the Sloth has a very short intestine, and the Seal a very long one. I have measured the length of the intestine of Pagophilus grcxnlandicus, and found it to vary between 50 and 56 feet in length. It is said that the livers of the Seals at Nova Zembla (Hemskirk) and in the southern seas possess poisonous properties : this is not the case with the livers of any of the Greenland seals ; for they are often eaten, and I never knew of any bad effect ensuing. The lymphatic glands are well developed, the glands being of great size, though not numerous, it being common to find only one in each axilla and groin. In the young Seals the lymphatics of the neck are subject to disease, which appears to be analogous to, if not indeed true scrofula: the glands swell and suppurate and pour out a purulent discharge ; and the animals subject to this do not increase in size. Many theories have been adduced to account for the Seal's capability of remaining with impunity so long below water. That of Buffon and the physiologists of his time was long celebrated : from their finding the foramen ovale open in a few instances, they twisted an exception into a rule, and accounted for it by this fcetal peculiarity. Dr. Wallace considers that this theory is erroneous, and from numerous observations he is satisfied that the open foramen must be very rare ; for in only one of the Seals which he examined did he |