670 SHUFELDT—OSTEOLOGY OF THE STRIGES. [Dec. 7, 
ion of the Owls were adduced. It then became manifest that two very 
distinct types of pterylosis existed in the group, and further it appeared 
that certain differences, already partly shown by Berthold (Bedtr. zur 
Anatomie, pp. 166, 167), of sternal structure coincided with the ptery- 
tological distinctions. By degrees other significant differences were 
pointed out, till, as summed up by Prof. Alphonse Milne-Edwards (07s. 
foss. dela France, ii, pp. 474-492), there could no longer be any doubt 
that the bird known in England as the Screech Owl or Barn Owl, with 
its allies, formed a section which should be most justifiably separated 
from all the others of the group then known. 
‘Space is here wanting to state particularly the pterytological distinc- 
tions which will be found described at length in Nitzsch’s classical work 
(English Translation, pp. 70,71), and even the chief osteological dis- 
tinctions must be only briefly mentioned. These consist in the Screech 
Owl section wanting any manubrial process in front of the sternum, 
which has its broad keel joined to the clavicles united as a furcula, 
while posteriorly it presents an unbroken outline. 
“In the other section, of which the bird known in England as the 
Tawny or Brown Owl is the type, there is a manubrial process ; the 
furcula, far from being joined to the keel of the sternum, often con- 
sists but of two stylets which do not even meet one another; and the 
posterior margin of the sternum presents two pairs of projections, one 
pair on each side, with corresponding fissures between them. Further- 
more, the Owls of the same section show another peculiarity in the 
bone usually called the tarsus. This is a bony ring or loop bridging 
the channel in which lies the common extensor tendon of the toes— 
which does not appear in the Screech Owl section any more than in the 
majority of birds. The subsequent examination by M. Milne-Edwards 
(Nouv. Arch. du Muséum, ser. 2, i, pp. 185-200) of the skeleton of an 
Owl known as Phodi/us (more correctly Photodilus) badius, hitherto 
attached to the Screech Owl section, shows that, though in most of its 
osteological characters it must be referred to the Tawny Owl section, in 
several of the particulars mentioned above it resembles the Screech 
Owls, and therefore we are bound to deem it a connecting link between 
them. The pterytological characters of Phofodi/us seem not to have 
been investigated, but it is found to want the singular bony tarsal loop 
as well as the manubrial process, while its clavicles are not united into a 
furcula and do not meet the keel, and the posterior margin of the ster- 
num has processes and fissures like those of the Tawny Owl section. 
Photodilus having thus to be removed from the Screech Owl section, 
Prof. Milne-Edwards has been able to replace it by a new form e/zo- 
dilus from Madagascar, described at length by him in M. Grandidier’s 
great work on the natural history of that island (Ozseaux, i, pp. 113- 
118). The unexpected results thus obtained preach caution in regard to 
