THE TESTICLE AND THE OVARY 



323 



eaiiy life produces changes in the general proportions of the 

 Ixxly. 



In the slieep, also, castration during immaturity lirings alxjut 

 changes in the hodily conformation. Thus, in breeds in which the 

 males only are horned, the skulls of the wethers may resemble the 

 females rather than the niales.i This is the case witli the Merino 

 sheep. In the Herdwick it has been shown that not only is the 

 presence of the testes necessary for the initiation of horn growth, l)ut 

 for its continuation, the liorns ceasing to grow forthwith after 

 castration and at any stage of horn development. Furtlier, uni- 

 lateral castration does not inhi))it the growth of the h(.)rns which 

 develop symmetrically in the normal manner.- 



FiG. 76. — Herdwick ram (normal). 

 (From Mai'shall and Hammond, 

 ■Jour. i>f Pliysiol.) 



Fig. 77. — Herdwick wether (caw- 

 trated young). (Fi'om Marshall 

 and Hammond, ■hwr. of PliijsinL) 



Differences in the form of the Itody have l)een noted hi eunuchs 

 as well as castrated animals. Thus, the bones of the limits tend to 

 lie longer than the normal, producing a conditio] 1 of gigantism. This 

 is due to an arrest in the ossification of the epiphyses (which is one 

 of the effects of castration). The same phenomena have lieen 

 described in castrated guinea-pigs, oxen, capons, and various animals.^ 



■ Selignian, " Exhibition of a Skull of a Domestic Sheep which had been 

 Castrated when Young," Proc. Zool. 80c., 1906. Changes in confoimation as a 

 result of early castration have also been described in other animals. 



" Marshall, " On the Effects of Castration and Ovariotomy upon Sheep," 

 Proc. Roi/. Soi\, B., vol. Ixxxv., 1912. Marshall and Hammond, "On the Efiects 

 of Castration on Horn Gi'ovvth in Sheep," Join: of J'liijsioL, vol. xh'iii., 1914. 

 In the Merino also castration is known to ari-est the growth of the horns of 

 the lum (Arkell and Davenport, " Horns in Sheep, etc.," Science, \'ol. xxxv., 

 1912). 



■^ Lannois and Roy, "Des Relations qui existent enti'e I'Etat des (-ilande.s 

 genitale.s males et le Developpement du Squelette" ; and Poncet, "De I'lntiuence 

 de la Castration sur le Developpement du Squelette," ('. R. rle la Soc. de Birjl.., 

 vol. Iv., 1902. See also Pittard, C. It de I'Acad. dcx Sn'cnre.i, vol. cxxxix., 1904, 

 who gives statistics showing that there is often an increase in size in eunuchs, 



