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Show 736 MR. W. A. FORBES ON THALASSIDROMA NEREIS. [June 21, as P. nereis. As regards the first-named species, there can be little or no doubt that the bird really dissected by Prof. Garrod, and called by him "Procellaria pelagica," was Wilson's Petrel {Oceanites oceanicus), as in this bird there are no caeca1, at the same time that the accessory semitendinosus muscle is present. The true Procellaria pelagica (of which I have lately dissected two perfectly fresh examples) agrees with the Fulmaridse, as defined by Prof. Garrod, in having caeca -, but no accessory head to the semitendinosus ; and Gymochorea leucorrhoa agrees in both these points with Procellaria pelagica. The so-called "Procellaria nereis" of Gould is therefore obviously not a true Procellaria at all; and this view is confirmed by other characters, such as the shape of its nostrils, the elongated tarsi, which are much longer than the mid toe3 and covered anteriorly with transversely arranged scutellse4, the very minute hallux, and the lamellar, concave form of the claws. It belongs, in fact, to the group of Oceanites, Fregetta, and Pelagodromu, but is not exactly congeneric with any of them. I propose therefore to make it the type of a new genus, to be called Garrodia, in memory of m y lamented friend A. H. Garrod, not only as a token of m y personal esteem for, and indebtedness to him, but also as some slight recognition of the thanks ornithologists generally owe him for the additions he made to our knowledge of the anatomy of birds. The genus Garrodia may be shortly defined as follows:- GARRODIA. Genus ex ordine Tubinarium OCEANIT^E maxime ajfine, tarsis pro digitis longioribus et antice scutellatis, necnon margine sterni posteriore integro distinguendum. Type Procellaria nereis, Gould. Garrodia is perhaps most closely allied to Oceanites, as already stated, but differs from that genus in having the tarso-metatarsi covered anteriorly with a series of transverse scutellse instead of being "entire," in their slightly greater proportional length as compared with the third toe5, in the even more minute hallux, and in the more flattened and lamellar form of the claws. The sternum too is posteriorly entire, whereas in Oceanites oceanicus it is slightly notched. The coloration of the two genera is also quite different. From Fregetta Garrodia may be easily distinguished by the very different proportions and forms of the nails and feet in that genus, and from Pelagodroma by its much shorter feet and entire tail. These four genera-Oceanites, Garrodia, Pelagodroma, and 1 Cf. also Macgillivray, in Audubon's ' Ornithological Biography,' v. p. 646. 2 Cf. Macgillivray, I. c. p. 313; also Wagner in Naumann's ' Vogel Deutsch-lands,' x. p. 556. 3 In Procellaria pelagica and Cymochorea leucorrhoa tbe tarso-metatarse is not longer, and may be shorter, than tbe 3rd toe. As against 21*5 and 21*5, and 23 and 26 millim. in the two first-mentioned genera, in the so-called Procellaria nereis tbe lengths of the two are respectively 34 and 26 millims. 4 In Procellaria pelagica the tarsi are pretty uniformly covered with somewhat irregular hexagonal scutes. 5 In a specimen of Oceanites oceanicus (in spirit) the middle toe measures 29 millim.; in one of Garrodia the length is 26 millim. The length of the meta-tarse in both is 34 millim. 6 ^ |
