Genus— M ELANOSTERNA. 
Melanosterna Blyth, Joum. As. Soc. Beng,, Vol. XV., 
p. 373, 1846 . . . . . . . . . . . . Type M. ancethetus. 
Medium-sized Terns, superficially agreeing with members of the genus 
OnychoprioTiy but having comparatively a much longer tail. The differences 
in the feet have been pointed out by Saunders {Proc. Zool. Soc. (Bond.) 1876, 
p. 665), who has carefully figured them. Yet that author lumped the two 
genera in with Sterna, though this action was obviously incorrect. 
Study of the plumages which the members of this genus show, indicate 
that the assumed close relationship of Onychoprion and Melanosterna is due 
to convergence. The juveniles of Hydroprogne, Gelochelidon, Thalasseus, 
Sterna, and Sternula all have very similar plumages, and all have similar 
winter changes. The juvenile-plumage of Onychoprion is so different, that the 
young has been described as an Anous, and such authorities as Saunders 
and Hartert have failed to recognise beautiful descriptions of the young 
plumage as applicable to this genus. For this reason alone the genus 
Onychoprion should be recognised. But the members of the genus Melano- 
sterna, though resembling in the adult stage those of the genus Onychoprion, 
differ as above stated, but, however, have entirely distinct plumages from the 
nestling to the adult. These will be detailed under the species. 
The 7ne7nbers of a natural genus 7nust have the plu7nages of the young very 
shnilar, however 7nuch the adults 7nay di^er. The reverse indicates convergence, 
and should he carefully noted as such. 
The earliest name for this genus 7nay be Thalassipora, but at present 
the first introduction of this name into literature is in Riippell, Syst. Uebers. 
Vogel Nord-ost Afrika, p. 140, 1845, thus : “ Thalassipora (Boje) infuscata 
Oder Sterna infuscata Lichtenstein Doubletten-Verzeichniss, sehr haufig bei 
Tor am rothen Meer.” ■ 
Hartert {Ratal. Vogel Mus. Senckenherg, p. 238, footnote, No. 462, 
1891) has pointed out that Ruppell’s specimens belong to this species, and 
not to Lichtenstein’s S. infuscata, which is the previous species. As there is 
nothing in the entrance of Ruppell’s Thalassipora to indicate this, the generic 
name must follow the specific, and therefore Thalassipora Ruppell is an 
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