136 Journal of Comparative Neurology 



in the models. The former two are the upper and lower nasal 

 glands. Born has fully discussed the position and structure of 

 these different groups, we will here only indicate upon the 

 model their position as found in several different types of 

 Anura. 



Figs. 6 and 7, Plate X, which are pen-drawings of wax 

 models of right cavity of tadpole of leopard frog, Rana virescens 

 show the glandular formation even at this stage, gla. It is ob- 

 served that in this case as in most of the larval Anura the 

 glands lie in close connection with the inner diverticle, id or jd. 



Fig. 7, Plate XI, which shows the dorsal view of an older 

 tadpole shows these glands lying upon the median aspect of 

 the cavity supported below by the fundament of the internasal 

 tract of cartilage, in. In this stage they have attained to larger 

 dimensions than in those before referred to. 



Figs. 3 and 4, Plate XI, are dorsal and ventral views re- 

 spectively of model of nasal cavity of an adult tree-toad Hyla 

 versicolor. In this stage both groups of glands are developed. 

 The upper nasal glands are seen at up, fig. 3, Plate XI, the 

 lower at lo in both figures. The latter are situated as in the 

 larvae upon the median aspect of the cavity but farther forward, 

 relatively, in the adult. The former lie upon the latero-dorsal 

 aspect just behind the anterior (or external) nares, extl. They 

 are much smaller than the lower nasal glands. 



In Bufo lentigenosus which is modelled in Figs. 1 and 2, 

 Plate XII, are also seen the upper and lower groups of nasal 

 glands, up and lo, situated relatively in the same positions as 

 above described. They are modelled as adherring to the re- 

 spective jdiverticles of the olfactory cavity for convenience and 

 durability of the models. 



The paucity of glands in Lacertila and OpJiidia as com- 

 pared with the other reptilia seems to be compensated by the 

 greater development of Jacobson's organ, which being a smaller 

 organ would not require such a profusion of glands. See Figs. 

 2, 3, 4, 5, 6, Plate IX, gla and jo. In mammals the Bowman's 

 glands are diffuse. 



