OF THE GLANDS OF THE SKIN. 205 



occur in groups of 3 or 4 close together. In the axilla, the 

 glands form a connected layer under the corium. 



According to Krause, there occur on a square inch of the 

 skin between tOO ;«nd 600 glands on the back of the trunk, 

 the checks, and the two superior segments of the lower 

 extremities; 924 — 1090 on the anterior part of the trunk, on 

 tin' neck, brow, the fore-arm, back of the hand and foot; 2685 

 on the sole of the foot; and 2736 on the palm of the hand. 

 The total number of the sudoriparous glands, without reckoning 

 those of the axilla, is estimated (somewhat too highly) by 

 Krause at 2,381,218, and their collective volume (with those 

 of the axilla), at 39,653 cubic inches. 



The vessels of the sudoriparous glands are particularly well 

 seen in those of the axilla (fig. 78); in others, the vessels may 

 also be seen here and there (best in the penis, where, for 

 example, glands of 0'36 ; " arc supplied by the most delicate 

 ramifications of an artery of O'Oe'", in their interior); and in 

 successful injections of the skin, the glands appear as reddish 

 corpuscles. Nerves have not hitherto been found in them. 



§ 67. 

 Intimate structure of the glandular Coil. — The sudoriparous 

 glands, in general, consist of a single much convoluted canal 

 (in one case, according to Krause, §'" long), twined into a coil, 

 which retains pretty nearly the same diameter throughout its 

 length, and terminates, either upon the surface of the coil, or 

 in its interior, in a slightly enlarged blind extremity. In the 

 large glands of the axilla alone, the canal is usually divided, 

 dichotomously, into branches, which subdivide, and some- 

 times, though rarely, anastomose ; and after giving off small 

 CEecal processes, each separate branch finally terminates in a 

 blind extremity. The glandular canals have either thin or 

 thick walls (fig. 79). The former (fig. 79, A) possess an 

 external fibrous investment, consisting of indistinctly fibrous 

 connective tissue, with scattered elongated nuclei ; internally 

 this is sharply limited, perhaps by a membra ua propria, and is 

 covered by a single, double, or multiple layer of polygonal cells 

 of 0'005 — - 007'", which in their chemical relations and other- 

 wise, correspond perfectly with the deep cells of pavement- 

 epithelium, except that they almost invariably contain a few 



