AVES. 85 
rior plate, with two lateral plates and a horizontal median and 
anterior one, which last is sometimes wanting. 
4. These taken together correspond to the T-shaped or cruci- 
form episternum of saurians, with the exception of the upper 
parts of the lateral plates, which are equivalent to the lateral 
prolongations of the coracoids in those animals. 
5. Sometimes the episternal apparatus remains membranous 
for the bird^s whole life. The place of ossification is generally 
in the median posterior plate. The superior apophysis, which is 
its result, bifurcates when it also extends into the lateral plates. 
Another point of ossification is close to the angle of the furcula. 
The prolongation of this, which forms the furcular apophysis, 
varies much in different species, sometimes extending to the lower 
end of the crest. The least-frequent ossification is that of the 
middle and posterior part of the median horizontal and anterior 
plate between the branches of the furcula and giving rise to the 
median apophysis. 
6. When the traehea enters the keel, the osseous walls of 
the cavity are part of the episternal formation. 
The plate illustrating this paper is most beautifully executed. 
The sternum of Grus cinereaj however, is represented as that of 
Cygnus musicus, though the mistake does not impair the value 
of the author’s observations. {Cf. Comptes Rendus, 1865, p. 727, 
Rev. Zool. 1865, pp. 118, 119, and ^Ibis,’ 1866, p. 116.) 
Haughton, Samuel. On the Muscular Mechanism of the Leg 
of the Ostrich. Ann. & Mag. Nat. Hist. 3rd ser. xv. pp. 
262-272, plates vi., vii. 
A very elaborate and excellent piece of descriptive anatomy. 
The author believes that in the digastric rectus femoris muscle 
lies the key to the explanation of the complieated muscular 
apparatus of the Ostrich’s leg. This mechanism Dr. Haughton 
considers to be a strong argument against the theory of natural 
selection. 
Homeyer, Alexander von. Das Wiederaufleben eines durch 
nasse Kiilte erstorbenen Zwerg-Fliegenf angers, Er'ythro^ 
sterna parva. Journ. fur Orn. 1865, pp. 221-2^'. 
An instance of resuscitation of a half-drowned cage-bird, not 
very remarkable. 
Landois, H. Die Eierschalen der Vogel in histologischer und 
genetischer Reziehung. Zeitschr. fiir Wissensch. Zoologie, 
1865, pp. 1-31, taf. i. 
The histological and genetic relations of egg-shells are con- 
sidered in much detail by the author, who bases his researches 
on an examination of the eggs of upwards of sixty species of 
birds. The plate represents the microscopic appearance of dif- 
