The upper mandible is furnished on each side (in the specimen examined by me) with a row or comb formed of 188 thin, elastic lamellae, obliquely bevelled so as to be pointed, and placed transversely to the longer axis of the mouth.
They arise from the palate, and are attached by flexible membrane to the sides of the mandible.

Those standing towards the middle are the longest, being about one-third of an inch in length, and they project fourteen one-hundredths of an inch beneath the edge.

At their bases there is a short subsidiary row of obliquely transverse lamellae.

In these several respects they resemble the plates of baleen in the mouth of a whale.

But towards the extremity of the beak they differ much, as they project inward, instead of straight downward.