330 THK PHYSIOLOGY OF REPRODUCTION 



as a result of similar experiments, reached an identical conclusion. 

 Ancel and Bouin stated, further, 1 as a result of a series of experiments 

 upon guinea-pigs, that the subcutaneous injection of extract prepared 

 t'nnii the interstitial tissue of the testis prevented the effects which 

 castration otherwise would have produced upon the rest of the 

 generative system and upon the skeleton. 2 Their results, therefore, 

 liller from those of Walker. In another paper Bouin and Ancel 3 

 Matt- that the injection of similarly prepared testicular extract in 

 guinea-pigs tends to promote growth. In the horse they found that 

 the development of the interstitial gland substance of the adult 

 coincided with the first occurrence of spermatogenesis ; but that 

 there was also a fn-tal interstitial gland, which disappeared at the 

 end of gestation, and a slightly developed gland composed of 

 xantliMehrome cells, which was only found in the immature animal. 4 



Tandler and Gross 6 have described the effects of subjecting the 

 testes to the influence of the Rontgen rays. They found that in 

 the roebuck the spermatogenetic tissue is destroyed but the 

 interstitial tissue is unaffected, and in correlation with this the horns 

 develop as in the normal male. Leo Loeb 6 found that in guinea- 

 pigs with undescended testes the interstitial cells were present, and 

 although spermatogenesis 7 did not go on, sexual desire was manifested. 

 Secondary male characters, however, might be absent, the animal 

 showing female somatic characters (see p. 346). Whitehead 8 from a 

 study of abnormal testes likewise found that the sexual instinct was 

 associated with the existence of the interstitial cells. The present 

 writer" found as a result of an experimental investigation in the 

 hedgehog that the growth of the accessory organs (vesicular, etc.) 



1 Bouin and Ancel, "Action de 1'Extrait de Glande interstitielle du Testicule 

 etc.," <'. /.'. <! l\\md. <!<>.< Sciences, vol. cxlii., 1906. 



Castration in early life, as already mentioned, is said to lead to a prolonged 

 retention of the cartilaginous unions between the bones, especially in those of 

 the limbs. 



3 Bouin and Ancel, " Sur PEffet des Injections de 1'Extrait de la Glande inter- 

 stitielle du Testiriile sur la Croissance," C. R. de la Sor. de BioL, vol. Ixi., 1906. 

 1 1'x.iiin and Ancel, "La Glande interstitielle du Testicule chez le Cheval," 

 /.>-,!. /;//>., vol. iii., 4th series, 1905. According to L6caillon the 

 mteiNtitial tissue in the mole's testis is functionally active during the breeding 

 season, when the testis is sixty-four times larger than during the resting period. 

 ("Sur le* Cellules interstitielles du Testicule de la Taupe considered en dehors 

 de la Periode de Reproduction," C. H. <l f In Soc. de BioL, vol. Ixvi., 1909.) 



Tandler and Gross, Die Biologischen i !,,, II, n^n <l<r Si-kuiidtiren Geschlechts- 

 mtn, Berlin, 1913. 



Loeb, " l.viations between the Interstitial Gland of the Testicle, Semini- 

 ferous Tubules and the Secondary Sexual Characters," Biol. Bull., 1918 



Seep. 164, Chapter V. 



Whiteli,-a<l, "A Peculiar Case of Crvptorchism, etc." Anat. Record, 

 vols. n. and iii., 1908 and 1909. 



9 Marshall, "The Male Generative Cycle in the Hedgehog: with Experi- 

 ment* ,,i, tli.- himrtional Correlation between the Essential and Accessory 

 Sexual Organs," Jour, of PhyinoL, vol. xliii., 1911. 



