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 by representatives from the California Museum of Vertebrate Zoology, from September 18 until November 7. Messrs. Halsted G. White, Joseph Dixon and J. Grinnell constituted the party, and one or more of these collectors worked in the immediate vicinity of Morro during the entire time. For a portion of this period the Elegant Tern proved to be a fairly common water bird on Morro Bay, or else on the outside ocean beach. The first one was positively identified on September 22, the last on October 4. Field notes follow.

As regards marks for field identification, there seems to be no outstanding positive feature by which the Elegant Tern may be distinguished at any ordinary distance from its congeners, unless conditions be such that relative size is determinable. From the notes of the field collectors just quoted, it is to be inferred that the pink blush of the lower surface can be seen clearly only under very exceptional circumstances. The relative slenderness of the bill of the Elegant might be used, if the proportions of this member in the Royal be vividly in mind or if birds of the two species be seen contemporaneously within short range.

Relative size is quite positively diagnostic of the-Elegant, if other sea-coast frequenting species of terns be in sight at the same time. Roughly, elegans is a large tern, yet decidedly smaller than its usual associate, the Royal. Some exact figures will here be instructive. Weight is, of course; a much more accurate index of the volume or "bulk" of a bird, generally speaking, than is any measurement Such as total length or length of closed wing. The seven