INNERVATION OF INTEGUMENT OF CHIROPTERA 307 



pighian stratum is composed of two layers of scattered cells. 

 The writer, however, finds that one layer of cells occurs quite 

 as frequently as two. The nuclei of the deeper layers of both 

 dorsal and ventral sides are slightly more oval than those of the 

 more superficial layers, the latter being somewhat flattened. 

 From the shape of the nuclei one would infer that when a single 

 layer occurs it is the outer one. In the Malpighian stratum of 

 the dorsal side of the patagium numerous pigment granules are 

 present, while in this stratum on the ventral side very little pig- 

 ment occurs. Aside from being somewhat thinner, the stratum 

 corneum does not differ from the corresponding structure in the 

 skin of the body. 



The tissue enclosed between the dorsal and ventral Malpigh- 

 ian strata of the patagium constitutes the corium, which varies 

 in thickness in different regions. In both the flying and inter- 

 femoral membranes it is thickest near the body, while in the more 

 distal areas it gradually becomes thinner. 



The corium is made up of three poorly defined strata of con- 

 nective tissue, a central, somewhat loose one, corresponding to 

 the stratum reticulare of the body integument, and two others — 

 one on either side — of denser tissue, more or less similar to the 

 stratum papillare. The chief arteries, which are accompanied 

 by the larger veins and nerve trunks, cause this stratum to be 

 much thicker in those regions where they occur than elsewhere. 

 Although the outer surfaces of this stratum are thrown into folds 

 to some extent, the writer has been unable to find papillae. 



In the stratum reticulare are contained the larger blood vessels 

 and nerves, and the striated muscle bundles and elastic bands 

 (Balken) first described by Leydig, whose results were later 

 confirmed by Schobl. Here also are found the secreting portions 

 of sweat glands, and the proximal third of hair follicles. The 

 outer stratum of the corium contains the central portions of the 

 hair follicles, their sebaceous glands, and the sweat glands. 

 Each follicle, with the sebaceous, sudoriparous and modified 

 sweat glands associated with it, is surrounded by a capillary 

 network. 



