156 MR. H. SAUNDERS ON THE LARIN.*. [Feb. 5, 



breeding-state, in the last of wbicb 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 

 in the darker portions of the webs with the advancing age of tbe indi- 

 vidual — 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 plu- 

 mage. 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 I 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 for- 

 wards 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 LarintB 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 dis- 

 tinct genera were erected for one and the same species in different plu- 

 mages; 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 Stemince. 



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,' xlii. p. 770 (1856), in which he makes 68 

 "undoubted" species and 22 genera of Larince alone, besides 5 

 more species which he considered doubtful — with justice, as re- 

 gards four of them, two being his own, one Bruch's, and one 

 Wagler's, whilst the fifth, Larus fidiginosus, is an excellent species 

 with which he was evidently unacquainted. To this succeeded the 

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