ON MUSCULAR COAT OF SWEAT-GLANDS. 233 



Biesiadecki, writing about the sweat-glands in bis article 

 on tbe skin, in 'Strieker's Histology/ observes : — " The gland 

 tube is composed of a sheath lined by enchyma cells. Tlie 

 sheath is a delicate transparent membrane, that when acted 

 on by nitrate of silver exhibits areas in which are oblong 

 nuclei (Czerny). In the larger glands, as in those of the 

 axilla, numerous longitudinal muscle cells lie on the outside 

 of this membrane, giving a striated appearance to the surface 

 of the gland. The gland tube is lined with a single layer of 

 conical or columnar cells." 



The following is an extract from the work on Histology 

 and Histochemistry, by Frey and Leukart: — "Among the con- 

 voluted glands we have the smaller and larger sudoriparous 

 organs, the ceruminous glands of the ear, and the lobules,occur- 

 ring in the conjunctiva of the edge of the cornea in mammals. 

 It is seldom that, as in the latter situation, they possess a 

 simple membrana propria. In most the wall is stronger, 

 this membrane being again enclosed within a layer of con- 

 nective tissue, between which structures muscular elements 

 may be disposed as a middle tunic, e.g., the large sweat- 

 glands of the axilla." 



Lastly, Krause in his Histology, recently published, says, 

 in treating of the sweat-glands : — " The canal consists of an 

 apparently structureless membrane to which externally is 

 applied a single or double layer of unstriped muscle-fibre 

 cells, while most externally we find a connective-tissue 

 adventitia." 



It will be seen from the above description that investigators 

 are generally agreed in assigning to the muscular coat of the 

 sweat-glands of the human subject a position external to the 

 " membrana propria." Dr. Klein^ first called my attention 

 to the fact that in the sweat glands of the sheep the mus- 

 cular coat is situated internal to the membrana propria. It 

 will be shown that this relation of the muscular coat of 

 sweat-glands holds in otlier animals, and from what can be 

 observed in the ceruminous glands of the external auditory 

 meatus of man that the same condition ohtained in the human 

 subject. 



Fig. o represents a transverse and longitudinal section of 

 part of the coiled tube of a sweat-gland, from a case of sheep 

 pox; the specimen Avas prepared by Dr. Klein. On examin- 

 ing the preparation from which the drawing was made, the 

 degenerated epithelial lining of the gland tubule can be 

 seen at a, appearing as a layer of pale rounded, granular, 



' " Research on Smallpox of Sheep," ' Transactions of the Royal 

 Society,' v. 16-4, 1S74, p. 229. 



