474 Miscellaneous. 



groups cease tow.ards the tip of the beak, where they are replaced 

 by Herbst's corpuscles ; the latter are so numerous that, in certain 

 preparations, they are seen to entirely fill the cavities of the spongy 

 bone which forms the skeleton of the beak. In the crow no glands 

 are seen in the median third of the beak ; the fowl, on the other 

 hand, shows well the two palatine groups of glands, which are in 

 contact the one with the other in the median line. 



b. The lower jaw and tongue. — The study of the glands of the 

 tongue is inseparable from that of the lower jaw. The organs are 

 those which, in the species in which they are found, have been 

 described under the name of sublingual and submaxillary glands. 

 In the just-hatched chick frontal sections affecting the base of the 

 tongue show two groups of glands of considerable size and another 

 smaller one. The most important group opens by a series of orifices 

 into the furrow which separates the tongue from the jaw. This 

 group is composed of glandular lobes which are developed, not 

 beneath the tongue, but in the floor of the mouth, beneath the 

 mucous membrane which covers the mandible, and which almost 

 come into contact with the bone. The second group of smaller size 

 occupies the two corners of the tongue, which, in frontal sections, 

 naturally presents the appearance of a triangle, with its base 

 uppermost and the apex beneath serving for the insertion of the 

 organ. In the two free corners of the tongue are found the groups of 

 glands which penetrate into the interior, as far as the three bones, 

 as yet in a cartilaginous condition, which form the skeleton of the 

 organ. 



The third group is situated in the actual thickness of the beak, 

 at the level of its free edge and internally to the inner margin 

 of the upper jaw (" en dedans du bord interne du maxillaire 

 superieur ") ; it is composed of somewhat small lobes, which open 

 opposite the edges of the tongue, and consequently correspond to 

 the glands of the second group. 



In the tongue of the adult duck, the two islets which form our 

 second group are greatly developed at the base, at the level of the 

 fatty-fibrous cushion which reduplicates the mucous membrane ; as 

 has been shown by M. Ranvier, they are non-existent at the tip. 



c. The pharynx and oesophagus. — In the chick some considerable 

 time before it is hatched we find in the pharynx only very volu- 

 minous and greatly swollen epithelial buds, comparable to the buds 

 of feathers, but penetrating inwards instead of projecting from the 

 surface. They form two groups — the one anterior, which occupies 

 the pharyngeal side of the laryngo-oesophageal septum, and the 

 other posterior, composed of two lateral masses which come into 

 contact in the median line. The house-sparrow furnishes us with 

 the complete development of this simple condition, for in this species 

 we may count as many as six distinct groups of glands — two median 

 and four lateral ones. 



The anterior median group is situated between the cesophagus 

 and the larynx ; it is quadrate in shape, and extends in breadth 

 from one mucous membrane to the other, so that, although we have 



