370 INTERNAL SECRETION 



specific stimulation of the skin ; the reflex movement is confined, 

 moreover, to a certain group of muscles. 



But the changes of puberty are not confined to the lower 

 centres of the spinal cord. That the functions of the cerebral 

 cortex are also affected is shown by the occurrence of sexual desire 

 and by the psychic changes which accompany the ' ' storm and 

 stress period." 



That all the somatic and psychic characteristics of puberty are 

 dependent upon the maturity of the genital glands, is rendered 

 probable by coincidence ; the fact is made certain by the results 

 of castration. 



Before passing on to this subject, however, it is expedient to 

 give a short description of the condition known as pubertas 

 praecox. 



Both the older literature and that of recent date contain numer- 

 ous descriptions of premature puberty, especially in girls. Those 

 cases, formerly regarded as freaks, in which girls of very tender 

 age showed menstruation, development of the mammae, growth 

 of hair at the pubes and axillae, and excessive growth, have been 

 repeatedly brought together and criticized (Kussmaul, Ploss, 

 Gebhard, Strassmann, Neurath). According to Neurath (1909) 

 the known cases of precocious menstruation are eighty-three in 

 number, but the descriptions of these are not in every instance 

 complete. Precocity in boys has been observed in forty-three 

 cases, many of which have been wrongly described as gigantismus 

 infantilis. The similarity between these cases and gigantism is 

 apparent only, the sole common symptom being the early tallness 

 of the subjects. The abnormal skeletal growth is the outcome of 

 very different causes. Skiagrams show that, in pubertas praecox, 

 there is accelerated ossification, and a rapid approach of epiphysal 

 ossification to the stage when the synarthroses close (Neurath). 

 This finding is in accordance with that of physiological puberty, 

 for in the latter condition also, the proliferation of the epiphyses 

 soon ceases. Gigantism, on the contrary, is characterized in all 

 its forms by persistence of the epiphysal synarthroses and the 

 abnormal height to which this leads. 



Pubertas praecox virilis is a condition affecting boys of 3 to 9 

 years of age. These children are remarkably large, heavy, and 

 well developed, and they show all the signs of puberty com- 

 mencing growth of hair on the face, pubes and axillae, deep voice, 

 and strikingly large external genitals, the testicle being the size 

 of a plum when in accordance with the age it should not exceed 

 the size of a bean. The psychic development sometimes corres- 

 ponds to that of puberty, though the subjects are more frequently 

 mentally defective, or even idiotic. 



The most important point in regard to the etiology of pubertas 

 praecox is whether or not the condition is primarily the outcome 

 of precocious development of the genital glands. We know that 



