BIRDS OF THE ROCKS. I7I 
and from calcareous shale near Fort Wallace, 
is named Hesferornis regalis. Under the gen- 
eric name Hesperornis have been grouped a 
number of species represented by skeletons 
more or less lacking completeness, but nearly 
enough perfect to show their affinities. A 
genus /chthyornis of most remarkable toothed 
birds has been found in the middle cretaceous 
rocks of Northwestern Kansas, and a number 
of interesting remains have been taken from 
the green sand and marl beds in New Jersey. 
It would not serve any purpose to catalogue 
here all the known fossil birds. I have hastily 
sketched a broken outline by way of preface, 
leading up to what geologists call the tertiary 
‘rocks. Here we find the true ancestry of our 
present birds—the rocks begin to sing and 
twitter and chirp. Now we hear a far-away 
chorus, the morning voices from the old, old 
woods. A very breath of flowers and foliage 
is suggested. 
In the Museum of the Boston Society of 
Natural History is preserved a beautiful speci- 
men from the insect-bearing-shale of Colorado, 
containing a nearly complete skeleton (with 
feather impressions of wings and tail) of a 
bird belonging to the “ oscine division of the 
FPasseres,” a division which contains all the 
singing birds now existing. This discovery of 
an oscine bird in the fossil form, dating far 
back of the age of man, leads the poet, not the 
scientist, to ask whether it may not be possi- 
ble, and even probable, that some of the more 
ancient fossil birds had that peculiar structure 
of the Zower larynx, or syrinx, necessary to the 
songster. The osczzes are not toothed birds, 
and teeth have been considered an index of a 
