Recently published Ornithological Works. 217 



A. stolidus than A. stolidus does from the seven others of 

 Mr. Sharpens species, and A. tenuirostris is placed in closer 

 relationship to A. caruleus than to A. melanogenys and 

 A. leucocapillus — propositions which cannot seriously be 

 maintained. These " keys " ought either to be avowedly arti- 

 ficial, as that given in Dr. Coues^s ' Key,' or they ought to indi- 

 cate the degrees of value attached to the different characters 

 employed in differentiating the component species contained 

 in the key. The latter is certainly the goal to be aimed at. 

 In the present case Mr. Sharpe will, we think, himself admit 

 that he has given a higher value to subordinate characters 

 than they are really entitled to, rendering his key to this 

 extent artificial, and teaching an erroneous view of the rela- 

 tionship the species bear to one another. 



Of Mr. Sharpens new species, A. superciliosus is apparently 

 the common Noddy of the West Indies (found also in the 

 Bay of Bengal !) . Can this really be specifically distinct from 

 A. stolidus, admitted by Mr. Sharpe as an inhabitant of North 

 America, i. e. the shores of the Gulf States ? A. plumbei- 

 gularis is from the Red Sea, the characters being drawn from 

 a single specimen in the British Museum. A single specimen 

 also furnishes the characters of a species from the Galapagos 

 Islands. This individual Mr. Saunders (P. Z. S. 1876, p. 669), 

 very properly, we think, considered to be in immature plu- 

 mage, and placed with A. stolidus. 



43. Sharpens Notes from the Ley den Museum. 

 [Notes from the Lejden Museum. Notes VI.-XII.] 

 These notes give the results of a visit to the Leyden Mu- 

 seum in the autumn of last year. In Note vi. Mr. Sharpe 

 describes two species of Arses, which he calls A. batantae 

 and A. aruensis. The former is from the islands of Batauta 

 and Waigiou, the latter from the Aru islands and New Guinea. 

 Objections to the selection of names for new species suggestive 

 of their geographical distribution have often been urged, owing 

 to the erroneous indication they convey of the range of the 

 species to which they are applied, should this subsequently be 

 found to be of wider extent. The names batantte and aruensis 



