VI. On the Myology of Opisthocomus cristatus. By J. Beswick Perrin, Demonstrator 
of Anatomy in Owens College, Manchester. 
Read November 4th, 1873. 
[Puates LXIII.-LXVI.] 
THis interesting bird has attracted the attention of naturalists from the time of M. 
LHerminier, in 1837, a physician in Guadaloupe, who communicated a paper to the 
Academy of Sciences on the anatomy of certain rare birds, and amongst others of the 
Hoazin, under the name of Sasa, by which it was said to be known to the inhabitants 
of Guiana’. 
There seems to have been considerable diversity of opinions amongst authors as to 
what family the Opisthocomus belonged to. These have been well summed up by Prof. 
Huxley in a paper ‘On the Classification and Distribution of the Alectoromorphe,” read 
before, and published in the ‘ Proceedings’ of, this Society, May 14th, 1868, as follows: 
—“T/Herminier is of opinion that the sum of the characters of the bird incline it 
towards the Gallinacee. He puts it, with Vieillot and Latreille, in the distinct family 
of the Dysodes, before the Pigeons and Gallinaceous birds. M. Gervais, on the con- 
trary, denies that it has any thing to do either with the Gallinaceous birds or with the 
Pigeons. He considers that it forms part of the great series of ‘ passeriform birds,’ 
but is so different from the others that it ought to form a separate order in this series, 
near the Scansores, and “near the Musophagide, though its affinities with the group 
may have been exaggerated.” Prof. Huxley further states that its peculiarities neces- 
sitate the placing of the bird in a special division of the Schizognathe. Whatever the 
true position of this bird may be, there are many peculiarities in structure which are, 
so far as my knowledge goes, found only in this bird. As regards the muscles of 
the shoulder-girdle, they are more condensed—and exhibit modifications, though of a 
minor character—than usually met with in birds. The attitude of the crop, its large 
size, its peculiar shape, and its still more peculiar nidus at once stamp the bird as one 
of no common kind*. I could not with any certainty obtain a drawing of the bird in 
its undissected condition. Having been in spirit so long, a sketch would only have 
perpetuated a falsity. 
* «Observations faites en Amérique sur les meeurs de différentes espéces d’Oiseaux-Mouches, suivies de quel- 
ques Notes Anatomiques et de meeurs sur l’'Hoazin, &c. par M. Emile Deville,” Revue et Magasin de Zoologie, 
tome iy. 1852. 
* I must here thank Professor Flower and Mr. Sclater for their kindness in allowing me the privilege of 
dissecting two beautiful specimens of this bird, obtained in Surinam by Hr. Kappler, of Albina, Maroni River. 
VOL. IX—PaRT VI. December, 1875. 3B 
