742 



PRION 



which seem to have no true remiges, the posterior edge of their 

 flijiper-like wings being formed of a greatly increased number of 

 little stiff feathers. 



The number of Primaries indicates a gradual reduction beginning 

 at the distal end. Omitting the few birds with 7 metacarpal quills, 

 we find that the 11th or terminal quill is never fully developed and 

 often scarcely functional. It is always much shortened and con- 

 cealed between its upper and lower covert, being not unfrequently 

 shorter and weaker than its covert, which in that case is sometimes 

 stiff. In some Rails and in many Passeres the 1 1 th quill is 

 very small indeed, or may be wholly absent. In this case, how- 

 ever, the upper covert is present as an apparently sujoernumerary 

 feather, provided that the 10th quill is not much reduced. This 

 last shews every intermediate stage between the largest develop- 

 ment possible as in Larus and Cypselm, and a degenerate condition 

 as in many of the so-called " Oscines novempennat^," ^ where the 10th 

 primary is supposed to be absent or at least extremely small and 

 concealed. In reality it is always present, even in the Dlcxidai, 

 while in some Hirimdiuidai it is more than half an inch, and in 

 Ideridai may be more than an inch long. In fact there are few 

 birds in which this " absent " quill does not measure the third of 

 an inch in length (see Remiges). 



PRION, a genus of Petrels established by Lacepede {Mem., de 

 rinst. iii. p. 514), on account of the denticulated or serrated edges 



Prion vittatus. (After BuIUt.) 



of their mandibles, and used as an English word by many writers. 

 To it are referred the Procellaria rittata of Gmelin and several other 



1 Equivalent to the " Tanagroid Passeres" of Mr. Wallace {Ibis, 1874, p. 

 410), or the "Passeres Fringilliformes " of the Catalogue of the Birds in the 

 British iluseuvi, vols, x.-xii. 



