: 
in the Classification of Birds. 21 
Clamatorial Birds, wherein the intrinsic muscles of the 
syrinx are fewer than four pairs in number, and where 
they are inserted into the middle points of the upper semi- 
rings of the bronchus; and consequently the apparatus 
here is of a less complicated and of a less perfectly devel- 
oped a character as an organ of voice. As examples of the 
first group we have the Thrushes, the Wrens, the Warblers, 
the Finches, the Crows and many others; and in the second 
group the Tyrant Flycatchers. 
Where some good work remains to be done, however, 
among the birds in this country, is in the various 
groups of the so-called water birds ; in ‘the Galline and 
in the Picide, and other groups. The form the trachea 
itself assumes is, of course, of prime importance in these 
birds, and in many cases the muscular part of the appar- 
atus will be found to be but feebly developed. 
ON THE ARRANGEMENT OF THE DEEP PLANTAR TENDONS IN 
BIRDS. 
Both Professor C. J. Sundervall and Professor Garrod 
have paid considerable attention to the disposition of these 
tendons in the feet of birds. If I mistake not, the first- 
named author was the writer who originally invited atten- 
tion to the fact that the tendon of the flexor longus hallucis 
was completely independent of the tendon of the. flexor 
perforans digitorum in the Passeres: and in view of this 
fact he grouped these birds together and as the Hoopoe 
(Upupa) exhibited the same condition, he included that 
form with them. Garrod pushed the matter much further, 
however, and made some very extensive dissections upon 
the deep plantar tendons in a great many different orders 
of birds. 
Irrespective of the plan of the foot, in all birds, in 
so far as its digits are concerned, there are two muscles 
present in the leg, which, arising from the tibia and fibula, 
send each a tendon to the toes as flexors, these muscles 
are the flexor longus hallucis and the flexor perforans digi- 
torum pedis. In passing through or over the hypotarsus 
of the tarso-metatarsus, at the back of the ankle-joint, the 
