RASORES. SCRAPERS. 105 



In Fig. 8, a^ is the lower part of the oesophagus ; 6, the proven- 

 triculus ; c^ c?, ^, g^ the stomach or gizzard ; h^ the commence- 

 ment of the intestine. The very strong lateral muscles, d^ e, 

 have their tendons inserted into an oblong or circular space of 

 a white colour, /, where the walls are very thin. A distinct 

 transverse muscle, ^, occupies the lower part or bottom of the 

 organ, and its fibres are inserted into the central space, f\ under 

 the edge of the kind of bridge formed by the tendons of the 

 lateral muscles ; while at the upper part there is also a muscu- 

 lar apparatus, ^, thinner than the rest. In Fig. 4, the oesopha- 

 gus, a, the proventriculus, 6, and the gizzard, c, cZ, are laid 

 open, the section being through one of the lateral tendons, /*, 

 of Fig. 3. At ^, are seen the oblong glands in the section of 

 the proventriculus, and on the inner surface of that organ their 

 apertures in the middle of rounded eminences. The lateral 

 muscles are seen at c7, e. The three coats or layers are marked : 

 the muscular or outer, /; the middle, r/ ; the inner or cuticu- 

 lar, ^, its inner surface longitudinally rugous. The mass of 

 food, of a cylindrical form, z, is impressed with rugae, from the 

 action of the organ. The intestine is long and rather wide, 

 and is seen convoluted at ^, /^, «*, j^ Jc^ in Fig. 1. The coeca 

 are in these birds very remarkable, as in them they receive 

 their greatest development, so as sometimes to exceed the in- 

 testine in capacity. They are represented by Fig. 2, in which 

 a, ^, is a part of the intestine ; and are seen coming off at c, 

 where for some length they are narrow, but afterwards enlarge, 

 are marked w^ith longitudinal lines, are contorted along the 

 course of the intestine, ^, /*, and terminate in nipple-like 

 points, «7, h. The structure of these parts will be more par- 

 ticularly explained when I come to speak of the Grouse and 

 Ptarmigans. 



The legs are generally strong ; the tarsi of moderate length or 

 short, stout, and either scutellate or feathered ; in the former case 

 sometimes having a knob or spur behind. Fig. 40. There are always 

 three anterior toes, connected at the base by membranes, which 

 however are sometimes scarcely apparent ; and w^hen a hind toe, 

 or poUex, exists, it is generally small, and elevated above the rest. 

 The claws are moderately arched, depressed, and obtuse. The 



