PHYSIOLOGY, CHEMISTRY AND PATHOLOGY 4G3 



(Figs. 2, 3). Hence, the normal growth and development of osseous struc- 

 tures is intimately associated with the elaboration of an internal secretion ' 

 by the testes. 



Fat Metabolism and the Testes. Gonadectomy is frequently followed 

 by an increased deposition of fat. This is also true in men of advanced 

 age and women after the suppression of the sexual activities. Such depo- 

 sitions of fat are peculiarly localized and to some extent characteristic in 

 each sex. Castrated males, especially men, are sometimes abnormally 

 lean, but the obese type is frequently observed among eunuchs and Scopts 

 (Tandler and Gross (&)). In these cases the excessive fat deposition is 

 noted in the mammae, nates, ventral regions and hips. The true capon is 

 excessively fat; the feeding of testicular substance to such fowls reduces 

 the tendency to obesity. 



Sex and Blood Composition. In insects there exists a sexual differ- 

 ence in the color and protein content of the hemolymph. However, these 

 differences are independent of the gonad, for they remain unaltered in 

 castrated individuals and in those carrying gonads of the opposite sex 

 (Steche). Further, where color differences exist in the blood of the two 

 sexes, it is not due to an enzyme in the male which is destructive 'to the 

 color found in the female hemolymph ; the metachlorophyll cannot be 

 bleached by the addition of male hemolymph (Geyer). The blood of 

 gynandromorphs is of necessity common to the dual sex characters ; how- 

 ever, the bisexual characters are maintained. Hence, the soma of such 

 forms is independent of any influence of the gonads. In higher animals 

 such blood pictures are not seen. The addition of blood from the male 

 to blood from the female will not normally cause hemolysis or the throwing 

 down of a precipitate. 



The adult male spider-crab contains less fat in the blood and liver than 

 the adult female (Smith). Parasitized males, as previously shown, gradu- 

 ally assume several of the a female" morphological characters ; in addition, 

 they take on the type of metabolism of the normal female crab. Similar 

 observations have been reported for fowls; the average total fat in the 

 blood of cocks is less than that of non-laying and laying hens (Riddle). 

 The blood of the human male contains a greater number of red cells, but 

 less fat than that of the female (Gettler and Baker). The rate of metab- 

 olism per kgm. of body weight and square meter body surface is slightly 

 greater in men than in women of corresponding weight and height (Bene- 

 dict and Emmes). There is a difference in the phosphorus content of the 

 blood of the male and female. The values for roosters, non-laying, and 

 laying hens are 6.43, 7.42, and 13.8 respectively (Riddle). Protein me- 

 tabolism apparently is not affected either by the presence or absence of 

 the testes. 



Gaseous Metabolism and the Testes. So far investigations of the 

 respiratory exchange in relation to the gonads have been very inconclusive 



