76 PROCEEDINGS OF THE ACADEMY CF 



1. Cymochorea leucorrhoa, Coues ex Viciliot. 



The specific characters of this, the common and abundant " Leach's Petrel," 

 being so well known, need not detain us. Its synonymy, however, is suffi- 

 ciently extensive and complicated to require attention. 



There can be no doubt, I think, that the Procellaria leucorrhoa, Vieillot, 

 Nouveau Dictionaire d'lfistoire Naturelle, tome xxv. 1817, page 422, was 

 based upon this species. Vieillot's description is : " Sept pouces et rtemi de 

 longueur totale ; la queue fourchue ; le bee, les pieds, les pennes alavies et 

 caudales, noires ; la reste du plumage couleur de suie, a l'exception des cou- 

 vertures superieures de la queue qui sont blanches, et d'un lisere gris-blanc 

 qui est a Pextremite' des pennes secondares de l'aile." Our author further 

 remarks that this Petrel " se tient sur 1'ocean" Atlantic "jusqu'au Brazil, 

 et peutetre encore au dela." In every respect the description so clearly and 

 completely applies to the present species, that no argument is needed to prove 

 the propriety of the reference. 



The next notice of the species that I have met with is by Temminck, Man- 

 uel d'ornithologie, 1820, ii. page 812, under the name of Procellaria Leachii. 

 The description is pertinent and complete, and the indication of the species 

 so unmistakeable, that the name Leachii has always remained the one in 

 common employ among ornithologists. 



In 1828, Dr. Fleming, in his '-History of British Animals," page 136, de- 

 scribes this species under the name of Procellaria Bulk kh. 



The citation " Procellaria pelayica, Pallas nee Linnams," is given by Bona- 

 parte as refering to this species. From what is now known of the range of 

 habitat of the latter, it would seem at best but a doubtful citation. 



In addition to the above, the species has been placed in numerous genera. 

 It is the Thalassidroma Leachii of Bonaparte. Consp. av. ii. 195; the Thalassi- 

 droma BullocMi of Selby, Ornith. ii. page 537: and the llydrobales Leachii ol 

 Boie. Isis von Okeii, 1822, p. 562. 



2. Cymochorea. melania, Coues ex Bonap. 



This, the second species of the genus, was first introduced by Bonn parte in fa is 

 Not. Orn. Delattr. in the Compt. Rend. 1 854, xxviii. p. 602. under the name of 

 Procellaria melania. The following is his diagnosis. " Nigro-coracina, vel in uro- 

 pygio ; subtus fuliginosa ; alis longissimis ; cauda brevi, sed profundi furcata ; 

 tectricibus omnibus omnino nigris." Unfortunately, however, as it afterwards 

 proved, he neglected to give any measurements; as a consequence, the suc- 

 ceeding species, homochroa. about to be described, has appeared in the ix. vol. 

 of thePacine Railroad Reports as the true melania, when it is in reality a 

 very different bird, though, like melania, it wants a white rump. Prof. Baird 

 has been enabled to obtain fromM. Pucheran the measurements of the true 

 melania, and these agree perfectly with a skin in the Smithsonian from Cape 

 St. Lucas, Lower California. As the species is yet rare in collections, and 

 one with which comparatively few ornithologists are autoptically ac- 

 quainted, a full description, taken from a typical example now before me, 

 niav not be out of place here. 



Form. The bill is large and robust, the mandibular rami of the intermaxil- 

 lary especially strong and prominent. The nasal tubes, as in T. Leachii, 

 measure a little less than half the length of bill. The bill is about two-thirds 

 the length of the skull ; about half that of the tarsus. The wings are mod- 

 erately long for this group, reaching only a little beyond the tail. The point 

 of the wing' is formed by the second primary alone; the third being interme- 

 diate between the second and the first; and the first intermediate between the 

 third and fourth. The tail seems rather long for this group and is deeply 

 forked, all the rcctrices being quite broad to their obtusely rounded tips. 

 The tibia is bare for a longer space than is that of T. Leachii. The legs are 

 short The tarsi are slightly longer than the middle toe and claw. The outer 



[Mar. 



