794 



THE APPARATUS OF THE SENSES. 



i th of an inch in width at their base. The nervous papillae are the 

 organs of touch, and contain either the corpuscula tactus (or axile bodies} of 

 Meissner or of Kratise. 



The SEBACEOUS GLANDS 

 lie beside the hair follicles, 

 each 

 two 



Fig. 365. 



TACTILE PAPILLAE FROM THE SKIN, SHOWING THE 



tactile corpuscles, OR " AXILE BODIES." 

 A, In the natural state ; B, Treated with acetic acid. 



hair being flanked by 

 glands. These small 

 organs are composed of a 

 very granular epithelium, and 

 are usually oval in shape. 

 (They are imbedded in the 

 substance of the derma, and 

 present every degree of com- 

 plexity, from the simplest 

 follicle to the compound 

 lobulated gland. In some 

 situations, their excretory 

 ducts open independently on 

 the surface of the epidermis. 

 Those associated with the 

 hairs are raceiform and lobu- 

 lated, consisting of glandular 

 vesicles, which open by short 

 pedunculated tubuli into a 

 common excretory duct, and 

 the latter, after a short course, 

 into the hair follicle. In some 



parts the ducts are short and straight ; in others, where the skin is thick, they 

 are spiral. They are lined by an inversion of the epidermis, which forms a 

 thick and funnel-shaped cone at its commencement, but soon becomes soft 

 and uniform. Sebaceous glands are met with in all parts of the body, but 

 are most abundant in those parts which are naturally exposed to the influence 



of friction, or require to be supple. Miiller 

 found in the Pig a special cutaneous gland, 

 somewhat resembling the sebaceous glands. 

 It is situated on the inner and posterior aspect 

 of the knee, and is from Jths to 2 inches in 

 length, and from J to J inch in width. In the 

 Sheep, there is found in the skin between the 

 claws, a particular inversion of the integument 

 that forms a small elongated pouch, curving 

 upwards and terminating in a cul-de-sac. This 

 is the interungulate gland, sinus, or bifleoc canal 

 (sinus cutaneus ungularum) ; it secretes a viscid 

 matter from glands which, according to Erco- 

 lani, are analogous to the sebaceous glands. 

 The pouch is lined with very fine hairs.) 



The SUDORIPAROUS GLANDS are deeper situ- 

 ated than the last (passing even into the 

 subcutaneous areolar tissue, where they are 

 surrounded by adipose cells). They consist 

 of a convoluted tube (or several tubuli pro- 

 duced by dichotomous subdivision) imbedded in the reticular layer of the 



Fig. 366. 



INTERUNGULA.TE GLAND OF SHEEP. 



a, Inner aspect of first phalanx ; 6, 

 Hoof, or claw ; c, Interungulate 

 gland ; d, Orifice of its duct. 



