'I'lu; ( ^il;iu(!(>iis Glands of ('oiiiiiioii Tuiuls. 323 



eeason late in April. ^ Others (Bufo fowleri Putnam) were col- 

 lected during the summer, and autumn in Washington, D. C. Ad- 

 ditional toads (Bufo fowleri Putnam) were collected at Blooming- 

 ton, Ind., at the breeding season in the middle of April, and dur- 

 ing May.^ 



The two species differ somewhat in the coloration and in the shape 

 and arrangement of the warts. The brief description of the color 

 pattern given in this paper, and the relation of the wart distribution 

 to the same, applies definitely to fowleri. On the other hand, the 

 detailed description of the skin and its glands has been derived 

 for the most part from the study of sections of americanus, whose 

 skin is thicker and whose warts are more massive. I have noticed 

 no essential differences in the minute structure of the parts and 

 do not deem it necessary to limit my statements to either of the two 

 species. All drawings and photographs of sections from adult 

 toads, except those horizontal to the surface, i. e., transverse of the 

 glands (Figs. 1, IG, 52, 69-76), and except Figs. 55 and 17, are 

 from americanus. 



Methods. Pieces of skin from different parts of the body have 

 been killed in the more common fixing agents, Perenyi's, Zenker's, 

 Gilson's, Flemming's, mercuric chloride and 4 per cent, formalde- 

 hyde. The last has proved the most satisfactory for the purpose of 

 this investigation. 



Many stains have been used. Delafield's hematoxylin with 

 Fischer's eosin, and Mallory's stain have been quite sufficient for 

 general detail ; Tanzer's orcein has been used to differentiate elastic 

 fibers. The material has not been prepared with the view to study- 

 ing the distribution of the nerves to the glands, or the nature of 

 the nerve endings. 



Photographs give the general relations which are essential to the 

 elucidation of this paper. Drawings have been made when finer 

 detail was desired. 



'The specimens of americauus found in tlie National Museum were kindly 

 placed at my disposal by Dr. Stejneger, for observation of external features. 



''I am indebted to Miss Mary C. Dickeson for the identification of a typical 

 specimen, one froni Washington and another from Bloomingtou, as Bufo 

 fowleri Putnam. 



