The Cutaneous Glands of (Vjinnion Toads. 331 



sacs are surrounded by a very thin sheath of loose connective tissue 

 which is continuous with the npper loose layer. About the sacs and 

 also the gland outlets, the finely divided fibers may form a homo- 

 geneous layer, similar or even continuous with that appearing at 

 the inner border of the epidermis. A definite network of elastic 

 libers surrounds the large gland sacs. That this is not the result 

 of pressure of the gland wall against the cutis is shown by the fact 

 that the fibers about the neck and collar form a stronger, more definite 

 network than about the sacs (Fig. 76). Here pressure could count 

 for very little. In the warts the bundles forming the compact stratum 

 are always more or less interwoven (Figs. 25, 40, 61). Transverse 

 strands are present, but they curve about the glands or are visible 

 as vertical strands through only a part of the depth of the compact 

 stratum. Nothing indicates that they take any special part in the 

 support of the gland sacs. 



Wherever warts occur, there is a change in all the strata of the 

 cutis proportionate to the extent and height of the wart. Greater 

 demands are made on the blood vessels, nerves and elastic fibers, 

 and there is an increase in the depth of the inner loose and, to a 

 less extent, in the outer loose strata. A great change likewise takes 

 place in the compact layer, because of the increased need of support. 

 The ventral skin is decidedly, but quite uniformly, uneven. The 

 inner loose and compact layers are relatively uniform in depth, and 

 in great part it is the outer loose layer which varies (Fig. 15). 



In the ordinary skin of the dorsal surface, especially at the edge 

 of the warts, papillae may occur. These are produced by the projec- 

 tion into the epidermis of an end bulb of spirally arranged cells, 

 at the base of which is a blood loop (Fig. 20). In the ventral skin 

 and over the warts are found what I shall call rudimentary bulbs. 

 In this case a small amount of cutis projects into the epidermis for 

 a considerable distance. It bears at its summit a single large cell, 

 the long axis of whose nucleus is perpendicular to the surface. 



Cutaneous Glands of the Toad. 

 Introduction. 

 The cutaneous glands with wdiich we are dealing consist of three 

 parts: neck, collar and acinus (Fig. 42) ; each is nuide up of many 



