SEROUS GLANDS OF THE VALLATE PAPILLAE 373 



tention is given to their histological structui'e, especially in the 

 better preserved material from older individuals. 



An attempt to include the taste buds in the models was met 

 with only partial success. Few taste buds appear in stages 

 before that of the 19 cm. fetus, but in this specimen the number 

 is relatively large. In all cases taste buds are more numerous 

 on the sides of the papillae although some are present on the 

 summit. They are also found on the dorsal surface in the 

 newborn. In none of the specimens is there any definite ar- 

 rangement of the taste buds in rows and tiers as has been 

 described in sheep and pig by Schwalbe ('68). 



In several specimens the lingual artery was injected and the 

 materia) sectioned and studied. A number of rather large ar- 

 teries ascend obliquely toward the serous glands about the 

 vallate papillae. Smaller vessels enter a gToup of glands and 

 then subdivide. Some of the latter vessels leave the glandular 

 tissue and supply the surrounding musculature. The arteries 

 do not follow the main ducts, or the terminal ducts of the 

 lobules. 



DISCUSSION 



As has been stated, the earliest glands are downgrowths of the 

 lower border of the papilla. Graberg ('98) figures the first out- 

 growths from the lateral wall of the papilla. My models show 

 that lateral outgrowths are not infrequent but that the gland 

 anlagen which first appear in about 8.5 cm. fetuses are on the 

 lower border (fig. 2) of the papilla. Oppel ('99) gives us an 

 excellent figure showing the topography of the serous glands. 

 The conditions there sho^\^l are confirmed in the present study 

 of the serous glands in a newborn. These glands extend 3-5 

 mm. on all sides of the vallate papillae as has been observed 

 by Oppel and by von Ebner ('73). The extent of the area occu- 

 pied by the group of serous glands about a papilla can be esti- 

 mated by reference to figure 1 which shows a single duct with 

 its gland groups. With thirty to fifty such ducts associated 

 with a papilla it is apparent that the glandular tissue must be 

 crowded and extend considerably beyond the surrounding fur- 



THE AMERICAN JOURNAL OF ANATOMY, VOL. 22, NO. 3 



