75 of the green varietj', and marked over the whole surface with lines that present very much the appearance of Chinese characters ; it resembles, however, specimens of the eggs of Uria troille, and I see no character by which it could be distinguished from them. Naumann gives, as one of the distinguishing features of the eggs of this bird, a peculiarly fine spotting or dotting, which gives the whole egg, at a short distance, the appearance of being uniformly dark colored. I saw no eggs at Gannet Rock that presented this pecu-liarity, but in the collection of the Smithsonian Institution there are eggs from California of another species, which are so marked. The species to which these eggs belong is as yet doubtful. Among the thousands of eggs of U. troille seen by me at Labrador, not one pre-sented this peculiarity. Four eggs measured : 79x47 mill. — 75 x 48 — 70 x 46 — 80 x 50. Uria lomvia,* Linn. Every available spot on the sides of Gannet Rock, not already occupied by the Gannets or Kittiwakes, had been taken possession of by the three last-mentioned species of Guillemots and the Razor-billed Auks ; their comparative numbers were about three of U. troille to two of U. lomvia and one of U. ringvia, and about one Auk to fifty Guillemots. I noticed nothing in the habits of these birds not already well known. According to Naumann, the eggs of U. lomvia resemble a turkey's in form ; though their shape is generally more ovate than that of the two preceding species, and the spots are frequently larger and less numerous, I have not been able to find any character by which they can certainly be distinguished. I have eggs, particularly of U. ringvia, that present these peculiarities as strikingly as any of the present species. Four specimens measured as follows : 79 x 47 mill. — 75 x 48 — 70 x48 — 70 x45. Mr. Theodore Lyman presented the following : — Descriptions of new Ophiurid^. I Ophioplocus, Lyman. (Nov. Gen.) Disc closely and finely scaled, above and below. Genital scales hidden. Teeth. No tooth-papillas. Mouth-papilla. Side mouth-shields wide, and nearly, or quite, meeting within. Arm-spines arranged along the outer edge of the side arm-plates. Upper arm-*This is the specific name given by Linnasus to Briinnicb's Guillemot in the "Systema Nature," edit. x. 1758, and consequently has priority over ana of Pallas. t "Otpig, snake; ttXokos, a twisted rope.