Acrocephalbie Genus Tatare. 39 



family, irrespective of other difterences i7iter se ? What 

 causes a wing to become rounded sufficiently to constitute its 

 possessor a Timeliine ? How far is tlie first primary to ex- 

 tend beyond primary-coverts ? How many decimal points 

 is the second primary to fall short of the third ? Is the third 

 ever to be permitted to extend to an equality with the fourth ? 



Really these questions are not frivolous^ but are very |)rac- 

 tical ; and they have come home to me in a very practical 

 manner while endeavouring to arrange my collection in 

 accordance with our latest authorities. Everywhere I come 

 upon some unhappy outcast, unknown to his supposed rela- 

 tives, and. waiting, we must charitably hope, for a home in 

 some future volume of a Timeliine catalogue. If from long 

 sedentary habits, from a dislike to reckless and aimless ad- 

 venture, some lonely Sylviad or Thrush has remained happy 

 and contented for countless ssecles on his lonely island rock, 

 is he to be spurned and cast aside, unworthy of a place among 

 Warblers or Thrushes, because disuse has somewhat shortened 

 the feathers of his pinion, or induced a slight exaggeration in 

 another rudimentary one ? • 



Take, for instance, Nesocichla eremita. Here we have an 

 island form, to all outward appearanca a true spotted Thrush. 

 It has not even an elongated bastard primary ; it lays the 

 eggs of a Blackbird ; its third and fourth primaries are 

 equal, and its second shorter than its sixth ; it has the spotted 

 plumage and every other Turdine character ; but its excur- 

 sions have been restricted, to the narrow limits of its native 

 Tristan d^Acunha, and therefore its wing has become weaker 

 and rounder than that of its fellows. " It will be treated of 

 in the Timeliidse " (B. M. Cat. vi. p. 104). I cannot but 

 demur to such a divorce, grounded on the accidents of its 

 insular condition, from the family of the Turdidse. 



But there is a want of consistency in the methods by which 

 the ranks of the Timeliidse are recruited. If Nesocichla 

 eremita is remitted thither because, though with a very small 

 bastard primary, it has a somewhat rounded wing, what shall 

 we say to the treatment of Sa.ricola arnotti, S. shelleyi, and 

 their allies, which have not a rounded wing, hut very 



