356 



J. A. MYERS 



the mid-line is approximately 35 mm. The abdominal pair of 

 glands stands somewhat isolated from the others, lying about 

 50 mm. caudad to the last thoracic and 25 mm. cephalad to the 

 first inguinal. As stated above, these glands lie near the level of 

 the umbilicus. Their distance from the mid-line is about the 

 same as, or slightly greater than, that of the last thoracic glands. 

 Each nipple of the first pairs of the inguinal glands lies in the 



Fig. 1 Ventnil aspect ol' adull Iriuale rat during lactation, to show location 

 and arrangement of the nipples (from Henneberg '00). 



inguinal region immediately medial to the thigh. The distance 

 from the nipple to the mid-line is approximately 12.5 mm. The 

 nipples of the second pair of inguinal glands lie in the most cau- 

 dal part of the inguinal region. They are located latero-cephalad 

 to the urethral orifice. Like the first thoracic glands, the nipples 

 of the last inguinal glands approach the mid-line, the distance 

 being only about 10 to 12 mm. It should be observed that in 

 passing caudad from the first thoracic glands the distance from 

 the nipples to the mid-line gradually increases imtil the last 



