Page 361, 
100 NOTES ON AN OSTRICH LATELY LIVING 
Mr. Macalister, in his description of the myology of this bird, has 
omitted a few of the muscles, some of which from the head will be 
described, together with those of the leg, which Mr. Frank Darwin 
has allowed me to introduce in this communication, from his notes 
and the dissection of that limb in this individual specimen. 
Pterygoid.—F rom the inferior surface of the posterior part of the 
palate-bone, and from the process of bone which connects it with 
the main portion of it, this is fibrous—also from the whole of the 
inferior surface of the pterygoid bone, extending inwards almost to the 
basisphenoidal rostrum.. 
The fibres are all directed backwards, and are inserted in two 
ways :—the outer, and some of those from the palatine longitudinal 
process, into the anterior surface of the transverse ridge at the 
angle of the mandible, which posteriorly receives the insertion of the 
digastric muscle; the inner, and others from the palate-bone, into a 
fibrous band which runs from the side of the median Eustachian 
aperture and its cartilaginous continuation to the prominent ridge 
behind and internal to the dondyloid articular surface for the man- 
dible, thus forming an arch under which run the arteries and veins 
to the head. 
This second portion of the muscle acts partly as an opener of the 
Eustachian aperture, partly asa retractor of the slightly movable 
pterygoid and palatine bones. 
Quadrato-mandibular—From the whole of the longitudinal ridge 
which forms the superior internal portion of the quadrate bone, and 
from the surface of the bone external to it. The fibres are directed 
outwards and downwards to be inserted into the inner surface of the 
mandible, in front of the articulation, not extending to the inferior 
margin, nor forwards further than the optic foramen. 
Quadrato-cranial.—From the back of the orbit, below and behind 
the origin of the recti muscles and the exit of the nerve, from a 
surface bounded above by a semicircular line, and extending down in 
the space between the orbit and the quadrate bone. The fibres are 
directed outwards to the corresponding internal surface of the quad- 
rate bone, a slight ridge separating the superior ones from those of 
the quadrato-mandibular. 
Gastrocnemius consists of two enormous masses of muscle blending 
together at their origins round the proximal end of the tibia, and 
separating lower down into the gastrocnemius anticus, which laps 
round the anterior half, and the gastrocnemius posticus, which sur- 
rounds the back part of the tibial section of the limb. Gastrocnemius 
anticus arises partly from the tibia, partly by blending with gastroc- 
nemius posticus; the latter arises from the distal extremity of the 
femur, the tendon of the quadriceps extensor and patella, and from 
