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Show 156 MR. H. SAUNDERS ON THE LARINEE. [Feb. 5, breeding-state, in the last of which the majority assume a black head or crest; but with the Gulls these conditions are more complex. Even in those species which are destitute of hood at all seasons there is a seemingly endless variation in the pattern of the primaries, the general tendency being to an increase in the lighter and a diminution m the darker portions of the webs with the advancing age of the individual- a rule which also holds good with many of those species the adults of which bear a hood in the breeding-season, whilst, on the other hand, there are others which exhibit the apparent anomaly of having a hood in the immature stage, and losing it in the adult plumage. The individual variations in size are even greater than in the Terns; and the range of the Gulls being, as a rule, less extensive, there are to be found several remarkable isolated and specialized forms, side by side with others, which are little more than climatic varieties of a general type. These circumstances have led to the establishment of a multiplicity of genera and of species, many of them exceedingly ill defined; and it was not until 1 had examined a considerable series of specimens here, and had visited the Museums of Paris, Leiden, Mainz, Berlin, and Copenhagen, for the purpose of identifying the types with the descriptions, that I could hope to clear up some of the more obscure questions. The literature of this group has been rendered especially intricate through the perverted ingenuity of two systematists who have undertaken its revision. Boie and Brehm are not guiltless in the matter of genera- and species-making; but their labours were chiefly confined to sorting the European Gulls backwards and forwards into fanciful groups, and to splitting up each species into three or four, which can, for the most part, be easily referred back to their origin. But when Bonaparte and Bruch undertook the revision of the Larinee of the whole world, they speedily enveloped the question in a perfect fog of synonymy, their only object being, apparently, to make as many genera and species as possible. Even distinct genera were erected for one and the same species in different plumages; the most closely allied forms were placed far apart, and widely divergent ones were united ; whilst it seemed to be accepted as an axiom that a different geographical habitat was sufficient to constitute a species. Revision followed revision; and to the work of the declining days of both these authors we owe at least half of the synonymy which encumbers these pages. It was their intention to perform a similar office for the Terns; but death cut their plans short, and to this is owing the comparative simplicity of the synonymy of the Sterninee. The result of their labours appears in Bonaparte's last completed list (for that in the ' Conspectus Avium' was never finished), in the •Comptes Rendus,' xiii. p. 770 (1856), in which he makes 68 " undoubted " species and 22 genera of Larinee alone, besides 5 more species which he considered doubtful-with justice, as regards four of them, two being his own, one Bruch's, and one Wagler's, whilst the fifth, Larus fuliginosus, is an excellent species with which he was evidently unacquainted. To this succeeded the |