354 Effa Funk Miihse. 



In the sijeeies dealt with in this investigation, I have never seen 

 small glands that were closely and definitely associated with the 

 necks of large glands. The small glands occur without any rela- 

 tion of position to the necks of the mature glands. 



How glands are replaced in the toad. I have shown that the ma- 

 ture glands may break down and degenerate. New gland buds may 

 arise in the epidermis at any time during the life of the individual, 

 in just the same way as the first glands arose in the tadpole. This is 

 the only mode of gland renewal in the toad. Buds do not arise in the 

 neck or collar of the mature type. An occasional nucleus and poison 

 sac is seen in the collar (Fig. 77). This condition might without 

 careful examination lead to the conclusion that a small gland is form- 

 ing, but it is simply a secreting cell out of place. 



Gradation a proof of one kind. The series of stages in the adult 

 toad, beginning with the gland bud in the epidermis to the mature 

 gland, has been described (pp. 345-348). There is a complete grada- 

 tion from the gland buds in the epidermis through stages called 

 mucus by authors(Figs. 26-35), located immediately below the epi- 

 denuis, and through the transitional glands (Figs. 36-41), to the 

 large typical, mature poison glands (Figs. 14, 42, 58-a), extending 

 deeper and deeper into the cutis as they develop. There is also 

 a series from the mature gland to^ the shrivelled, empty sacs (Figs. 

 24, 53, 58), and finally to a vanishing fragment (Figs. 23, 57), 

 lying below the largest mature glands. There is no evidence that 

 the poison glands are developed in lany way except through the so- 

 called mucus glands, which are nothing more nor less than young 

 immature poison glands. There are never any degenerate glands, 

 except through injury, seen in the outer battery to which the so-called 

 mucus glands are confined. They do not degenerate except acci- 

 dentally, but are stages in the development of the large mature glands. 



Distribution of glands, a proof. Facts regarding the distribution 

 of warts, and of different stages of glands over the whole body, 

 strengthen the evidence that but one kind of gland exists in the cutis 

 of the toad. The glands develop into the mature stage in all regions 

 of the body. They reach that stage in greater numbers on the dorsal 

 surface where they crowd together and form the parotids and other 



