NATURAL SCIENCES OF PHILADELPHIA. 189 



the preponderance of authority is in favor of the adoption of that of Illiger. 

 I can, however, discern no cause why Lacepede's name should be superseded. 

 The reasons given by Illiger, in proposing Haladroma, and by Lesson in 

 founding Puffinuria, certainly seem invalid. To G. R. Gray is. I believe, due 

 the credit of restoring the rightful appellation of Lac6pede. 



The type which represents the genus, although so curiously anomalous, is 

 so well known, that a detailed description would be out of place here. Only 

 a few of its more salient points need be noticed. 



The perfectly vertical nostrils are surrounded by an elevated wall, whose 

 contour, in consequence of a slight emargination posteriorly, and a corres- 

 ponding protuberance anteriorly, on the median line, is somewhat cordiform. 

 The wall has considerable thickness basally ; but much bevelling superiorly 

 gives it an extremely thin edge. The internasal septum is moderately thick ; 

 and from either side a process projects transversely into the nasal orifice. In 

 shape each nostril is suboval ; being somewhat elongated anteriorly, and a 

 straightening of its inner border being produced by their mutual appo- 

 sition. 



The dertrum or unguis is long, reaching quite to the nostrils ; and, for this 

 family, is only moderately uncinated. Except at its extreme base it is dis- 

 tinctly carinated, aud its sides are much compressed. 



The myxa is unusually small and narrow, with a very acute tip, and ex- 

 tremely concave gonys. The sulci separating the myxotheca from the rest of 

 the mandible, and the lateral one on the gnathidia are strongly marked. 



The unusual amount of divarication of the concavo-convex gnathidia, which 

 causes so wide a submentum, is, in the upper mandible, accompanied by a 

 corresponding dilation of the lateral elements ; which latter are also turgid 

 and inflated. 



The tarsus is excessively compressed, and at the same time very deep 

 antero-posteriorly ; giving to its transverse section a narrowly elliptical shape, 

 like that which obtains in the Colymbidas. It is reticulated as in the Procel- 

 laridse, and also the majority of the Alcidcc, though Mtrgulus has anteriorly 

 transverse imbricated scales. The proportions of the anterior toes are as in 

 the other Procellariidce. 



In the wings and tail the urinatorial aspect is most decidedly marked. 

 The very short wings, with their stiff, falcate, subacuminate primaries hardly 

 reach to the end of the exceedingly abbreviated tail. 



The plumage is essentially diverse from that of any other Prgcellaridian, in 

 its compact imbrication, and oily glossiness, which comes nearest to that of 

 the Loons; and is eminently adapted to resist the action of the water in 

 which the habits of this species cause them so constantly to be submerged. 



Concerning the number of species *o be enumerated authors are greatly at 

 variance. To a comparatively recent date but a single oue was supposed to ex- 

 ist. M. Temmiuck, in figuring the type of MM. Quoy and Gaimard's P. 

 Berardii, is of opinion that both urinatrix and Garnoti should be referred to it. 

 M. Lesson, after describing Puffinuria Garnoti in 182G, doubtfully refers it to 

 Proc. urinatrix Gm.* Prince Bonaparte unites Garnoti and urinatrix, and con- 

 siders Berardii&s distinct. Mr. G. R. Gray, and more recently, Dr. H. Scble- 

 gel agree in regarding all three of the supposed species as valid. A sufficient 

 amount of material is not at my disposal to settle these doubtful points. In 

 a considerable number of specimens from various localities I can see what 

 has been called P. Berardi, differing in some respects from the ordinary type : 

 but have failed to detect tangible differences indicating three species. Very 

 possibly, however, none of the specimens before me indicate the true urinatrix, 

 as distinguished from Garnoti. 



The three supposed species are based entirely upon size: a varying degree 

 of length or robustness of bill : and coloration of the feet. Some specimens 



1866] 



Traite d'Oraith 1831, p. 720, No. 144. 



