THE TONGUE OF THE SHEEP. 41 



Of late years, under the name first of General Anatomy, and, now, 

 of Histology (f<n-os, histos, a web, and Aof?, logos, a discourse), these 

 tissues or textures have been very minutely studied by aid of the 

 microscope and certain chemical reagents ; and it is truly remarkable 

 what a variety of beautifully adapted minute elementary tissues have 

 thus been discriminated both in animal and in vegetable organisms. 



TEXTURES IN THE TONGUE AND LARYNX OF A SHEEP. 



The tongue, larynx and upper portion of the trachea or windpipe of a sheep, 

 attached to a piece of the middle of the lower jaw-bone, being obtained from a 

 butcher, a dissection like that represented in Fig. 16 may be readily made with 

 a little care, the parts being first fixed with strong pins upon a piece of board, 

 and then portions being removed from the right side of the organ. Examples 

 of every kind of tissue will be met with in such a dissection ; and, from it, as 

 the tissues of the sheep more nearly resemble the human textures than those 

 of the rabbit, their naked eye appearances, their mutual relations, and their 

 adaptation to particular purposes, will be better understood preparatory to 

 studying their microscopic characters in the human frame. 



The solid walls of the larynx, c, and also the firm rings which nearly sur- 



Fig. 16. A view of the right side of the tongue, larynx, and two upper rings of the trachea or windpipe 

 of the sheep, attached to a piece of the lower jaw ; the whole being dissected to show its constituent parts, 

 c, the thyroid cartilage of the larynx: below this are two cartilaginous rings of the trachea, all being held 

 together by intermediate membrane. Above the larynx are the several pieces of the hyoid bone and its 

 adjuncts, me is a simple membrane, containing little lobules of fat,/, m, m, m are various muscles of the 

 tongue, p a is the papillary mucous membrane by which it is covered, a is the lingual artery entering 

 the tongue, and v, the lingual vein passing out of it; the branches of both vessels are seen in the substance 

 of the organ, n (to the left) is the hypoglossal nerve, the muscular or motor nerve of the tongue ; n (to ;*e 

 right) is the lingual branch of the fifth nerve, going to the mucous membrane, and constituting the sensory 

 nerve of the tip of the tongue, g is the sublingual gland, one of the salivary glands, the ducts of which end 

 in the larger duct, d, of the submaxillary gland, which is not seen here. The duct d opens into the mouth 

 beneath the tip of the tongue, b is the section of the lower jaw-bone showing the cancellated structure, 

 and containing one of the incisor teeth, p is the periosteum covering that bone. (The Author.) 



round the trachea, afford an example of one variety of that white semi-opaque, 

 firm, elastic substance, called cartilage or gristle. Parallel with the upper bor- 

 der of the larynx are the several pieces of the lingual or hyoid bone, which is 

 large in the sheep, and presents us with an illustration of osseous tissue, which, 

 however, is better exemplified in the lower jaw, 6. Both the cartilages and 



