THE COMMON BLACK GROUSE. 
179 
assemble at feeding times, for of late years this spe- 
cies has increased to an immense extent, and from 
the life of the hens being to a certain degree pro- 
tected, a sufficient breeding stock is always kept 
up. At the season of their thus assembling in flocks, 
they are extremely shy and wary. 
The plumage of the adult male is, on all the upper 
parts, of a rich steel -blue j on the under parts, pitch- 
black, which duller colour also is seen on the second- 
aries and wing-coverts. The secondaries are tipped 
with white, forming a bar across the wings conspicu- 
ous in flight, and the under-tail coverts are of the same 
pure colour. The form of the tail is, however, the 
most curious or anomalous structure in this bird, dif- 
fering from all the others, (except one, where it is very 
slightly indicated,) in being forked, and having the 
feathers bending outward. From this circumstance, 
it has been formed into a subgenus by Swainson, 
under the title Lyrurus, and is made in that gen- 
tleman’s system to represent the fissirostral form 
among the Tetraonidae, bearing analogy in its forked 
tail and glossy plumage to the Drongo shrikes of 
Africa and India. The female bears the more unob- 
trusive colours which run through the sex in the rest 
of the group, and has a chaste and beautiful arrange- 
ment of brown, black, and greyish-yellow. The fork 
of the tail is very slightly seen. 
From the Grouse and Ptarmigan we appear to ar- 
rive naturally at those birds which fill their situation in 
