282 PHARMACEUTICAL BACTERIOLOGY 



ries develop just the same and lactation is not interfered with. The same 

 phenomenon has been observed in women from whom for some reason 

 or other it has been necessary to remove the ovaries during the gestation 

 period. 



It has been claimed by some investigators that the development of 

 the mammaries during pregnancy is dependent upon secretory activity of 

 the placenta ("after-birth"). They have urged in support of this theory 

 that mammary development persists in pregnant animals, regardless 

 of the death of the fetus, just as long as the placenta remains. Further- 

 more, placental extracts have been reported to be active stimulants to 

 lactation. Other evidence seems to support the assumption that there is 

 some substance derived from the fetus which stimulates the mammaries, 

 and the injection of fetal extracts in normal animals brings about an en- 

 largement of the mammary glands. Possibly both factors are involved. 



Therapeutically, the importance of a product made from the mammary 

 gland seems to lie in its effect in neutralizing excess ovarian secretion, and 

 this has resulted in a preparation of this character being applied to the 

 control of menstrual excesses having their origin in over-functionating of 

 the ovaries. A still more interesting application of mammary gland treat- 

 ment has been in fibroid tumors of the uterus. On first consideration 

 such a therapeutic measure looks preposterous, but the theory is that 

 fibroids have their origin to a large extent in uterine congestion. Sev- 

 eral investigators have reported that the use of mammary extracts has 

 resulted in an arresting or disappearance of these fibroids, and while the 

 evidence thus far produced is by no means conclusive, the possibilities 

 of such treatment warrant further study. 



2. The Ductless Glands 



The ductless glands are without ducts, they are small in comparison 

 with the duct glands and occupy well protected positions in the body. 

 They consist mainly of epithelial cells which are in close relation to the 

 walls of capillary blood vessels and lymphatics, and in some instances, if 

 not all, under the control of the cerebro-spinal nerve system. By reason 

 of their relationship to the blood circulation, they have been called vas- 

 cular glands and blood glands. Some recent observations would indicate 

 that the sympathetic nerve supply has a very intimate relationship to 

 the ductless glands as well as to the epithelial cellular structure of the 

 capillaries. 



While there is much which is as yet undetermined with regard, to the 

 ductless glands, there is much that can be said with some degree of definite- 

 ness. They most certainly secrete substances which are necessary to 

 the proper or normal correlative functioning of organs. They contain 



