192 
GENEBAL OBNITHOLOGY. 
notes qualities of matter in bulk, as density, roughness, temperature, etc. Gustation, matter 
dissolved in water — fluidic. Olfaction, matter diffused in air — aeriformed. Audition, atmos- 
pheric air in undulation. Visi07i, an ethereal substance in undulation. All animals are proba- 
bly also susceptible of hiogenation, which is the affection resulting from the influence of biogen ; 
a substance consisting of self-conscious force in combination with the minimum of matter 
req^ired for its manifestation.^ 
c. Myology: the Muscular System. 
Muscular Tissue consists of more or fewer amoebiform animals ) separate colonies of which 
creatures, isolated in various parts of the body, compose the individual different muscles. They 
are enveloped in fibrous tissue, the sheets of which are called fasciae, and the ends of which, 
usually attached to bones by direct continuity with the periosteal covering of the latter, form 
tendons and ligaments. The muscle-animals belong to a genus which may be termed 
Myamoeba, differing from other genera of the amcebiforms which compose the body of a bird 
less in their physical character of being elongated and spindle-shaped, or even filiform, than in 
their physiological character of contractility. Under appropriate stimulus, as the passage of a 
current of electricity, or the wave of biogen- substance which constitutes a ^'nerve-impulse," 
Myamceh(B shorten and thicken, tending towards a state of tonic contraction which, if completed 
and long sustained, would cause them to become encysted as spherical bodies ; but extreme con- 
traction is never long continued. By alternate contraction and relaxation all the motions of the 
body in bulk are effected. The capacity of, or tendency to, contraction is called the tonicity of 
muscular fibre. The simultaneous contraction of any colony of Myamoebce pulls upon the attach- 
ment of the muscle at each of its ends ; in some cases approximating both ends ; oftener moving 
the part to which one end is attached, the other being fixed. The action of a muscle is upon 
the simplest mechanical principles, — nothing more or less than pulling upon a part, as by a 
rope, the line of traction being exactly in the line of contraction of the muscle ; though it is 
often ingeniously changed by the passage of tendons around a corner of bone, or through a loop of 
fibrous tissue, as if through a pulley. Such movements as those of a turtle protruding its head, 
or a bird thrusting its beak forward, where muscle seems to push, are fallacious ; when analyzed, 
the motion is invariably resolved into simple pulling. The swelling up of a muscle in contract- 
ing must indeed impinge upon neighboring parts and shove them aside ; but that is an extrinsic 
result. Muscles contract most powerfully under resistance to their turgescence : what is effected 
by the fasciae which bind them down ; — what the athlete seeks to increase by bandaging his 
swelling biceps. There are two species of Myamoeba. M. striata is the ordinary striped fibre 
of voluntary motion, and also of some motion not under control of the will, as that of the heart. 
This species is usually of a rich red color (pale pink in many birds of the grouse family), and is 
the ordinary " flesh " of the body. The other species, M. lavis, composes the pale or colorless 
smooth fibre of the involuntary muscles, as those of the intestines, the gullet, etc. A species of 
contractile tissue commonly referred to the genus Desmamoeba (indifferent connective- tissue 
cells) is very near Myamoeba Icevis ; example, mammalian dartos. The movements of erectile 
organs, as the neat combs over the eyes of grouse, or the turkey's caruncles, are not in any sense 
myamcebic, but depend mechanically upon influx of blood. 
The Muscular System of Aves can only be touched upon ; it is impossible in my limits 
to even name all the muscles, much less describe them. I can only note the leading peculiarities, 
and present a figure in which the principal muscles are named. 
1 The reader who may be interested to inquire further in tliis direction is referred to a publication entitled : — 
Biogen : A Speculation on the Origin and Nature of Life. Abridged from a jtaper on the " Possibilities of Proto- 
plasm," read before the Philosophical Society of Washington, May 6, 1882. By Dr. Elliott Coues, etc. Washing- 
ton, Judd & Detweiler. 8vo, pp. 27. Second ed., Boston, Estes & Lauriat, 1884. 
