54 PROCEEDINGS OF THE ACADEMY OF 



riautus, Klein, Prod. At. p. 140. In part. 



Arctica^ Mcehring, Av Gen. 1752, p. G5. Tj-pe Plautus columbarius, Klein, Gray, 



Genera, iii, 1849, p. 644. Type Alca alle, Linn. 

 Alca, Linnasus, S. N., i, 1758. In part. 

 Ui-ia, Pallas, Zoog. R. A. 1811, ii. In part. 



Bill very short, culmen only three-fourths the tarsus, very stout, scarcely 

 compressed, obtuse at the tip, as wide as high at the base, the .sides of both 

 mandibles convex or vaulted, the tomial edge of the upper greatly inflected, the 

 culmen very convex in outline, with a broad flattened ridge, the rictus ample, 

 much decurved towards the end, the gouys straight, very short, the inferior 

 mandibular rami correspondingly elongated, widely divaricating, the interra- 

 mal space very broad, the nasal fossae short, wide, deep, partially feathered. 

 Nostrils subbasal, short, more broadly oval, or more nearly circular than in 

 any other genus except Synlldiborhimphus. Wings rather longer than usual in 

 this family, acutely pointed. Tail of ordinary length, much rounded, the fea- 

 thers rather narrow and subacuminate at tip. Feet small and weak ; tarsus 

 scarcely compressed, anteriorly broadly scutelHte, posteriorly finely reticulate. 

 Toes of the usual proportionate lengths. Size very small; general form very 

 compact, stout. 



A peculiar genus of the Alcidse, the most essential characters of which, as 

 usual in this family, are found in the bill, though the. other members otter some 

 appreciable, if not salient features. The squat bunchy shape of the single spe- 

 cies is very noticeable. 



This is the genus through which a certain type of structure found among the 

 Longipennes inosculates with the Pygopodes. The relationship of Pelecanoides 

 urinalriz to Mergulus alle is one of strong analogy, if not of actual affinity, as 

 has been elsewhere already pointed out by the writer.* Aside from the obvi- 

 ously Procellaridian characters of the bill, Pelecanoides (representing the sub- 

 family Ilalodroiiiinne) is strictly a Pygopodous genus, and is very nearly iden- 

 tical with Mergulus in all the details of external structure, and has much the 

 same general habitus. It is certainly the connecting link between the ma- 

 cropterous and brachypterous natatores, holding so strangely anomalous a 

 l^osiiion betwixt the two, that it cannot be with much propriety included under 

 either. It seems entitled to the rank of a family, to take place between the 

 Procellariidx and Alcidse. 



Mergulus alle, {Ray) Vieill. 



Mergulus melotioleucus, Ray, Syn. Av. p. 125. Stephens, Shaw's Gen. Zool. xiii, 

 1825, p. 345. Brandt, Bull. Acad. St.-Petersb. ii, 1837, p. 347. Brewer, oct. 

 ed. Wilson's Orn., with notes by Jardine, 1840, p. 658, fig. 315. Fleming, 

 Hist. Brit. Auim. 1842, p. 135. Thompson, Nat. Hist. Ireland, iii, 1851, 

 p. 218. 



Columba grcenlandica, " Albanus, Av. p. 81, pi. 85. Gunn., Act. Nidroff, i, p. 

 206, pi. 6." 



Plautus columbarius, Klein, Prod. Av. p. 146, No. 1. 



Alca alle, Liunseus, S. N. ed. x, i, 1758, p. 131, No. 6. Id. ibid. ed. xii, 1766, i, 

 p. 211, No. 5. Briinnich, Urn. Bor. 1764, p. 26, No. 106. Hermann, Tab. 

 Affin. Anim. p. 149. Miiller, Zool. dan. Prodr. p. 17, No. 142. Latham, Ind. 

 Orn. ii, 1790, p. 795, No. 10. Donndortf, Beytr. Zool. ii, pt. i, 1794, p. 823, 

 No. 5. — Donndorfi's Var. B is Candida Lath. — Wilson, Am. Orn. ix, pi. 74, 

 fig. 5. Schlegel, Urinatores Mus. Pays-Bas, ix livr. 1867, p. 20. 



Una alle, Pallas, Zoog. R.-A. ii, 1811, p. 369. Temminck, Man. Orn. ii, 1820, 

 p. 928. Bonaparte, Obs. Wils. 1826, No. 238. Audubon, Orn. Biog. v, 1838, 

 p. 304, pi. 339. 



Uria [Mergulus) alle, Bonaparte, Synopsis, 1828, p. 425. 



* Cf. Pr. A. N. S. Philada. May, 18G6, pp. 172, 189. 



[Jan. 



