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area: in testes preserved in formalin very minute superficial ducts, 

 forming a network in the green region and containing sperms, can be 

 distinguished by the aid of a lens, and these unite to form the efferent 

 ^ucts. 



Arising from the inner border of the testis a network of vasa 

 efferentia (or better, ductuli efferentes) can be made out even with 

 the naked eye (Fig. 1): by tracing these in serial sections we were 

 able to distinguish six of these ducts passing in the peritoneum, 

 ventral to the spermiduct (Fig. 2), as far as the region in which the 

 coiled anterior mass of the spermiduct and the mesonephros abut 

 against one onother. Here they all unite to form a larger duct which 

 extends forwards longitudinally and enters the complicated coil of the 



Fig. 2. Transverse section through region indicated by a in Fig. 1 (X about 13). 

 b.v. blood-vessel; c.t. connective tissue; ef.d. efferent duct, cut longitudinally; ms. 

 mesonephric tubules ; ms'. ducts of mesonephric tubules which open into spermiduct ; 

 sp.d. spermiduct containing spermatophores ; sp.d'. part of the spermiduct containing 

 loose sperms, intermediate between the longitudinal collector and sp.d. 



spermiduct, first apparently bifurcating and the two branches again 

 uniting (Fig. 1). Free sperms could be recognised in the efferent 

 ducts and in the longitudinal collecting duct (Figs. 1 and 3), the further 

 course of which latter we traced through a long series of sections. 

 There is no doubt that the longitudinal collector becomes actually 

 continuous with the spermiduct, and that there is no connexion between 

 the efferent ducts and the mesonephric tubules ^) (Fig. 4). 



1) We have not made a special examination of sections of this 

 region in Plagiostomes, but it may be here stated that in Scyllium 

 canicula some of the posterior efferent ducts end blindly in the 

 adult, and that in certain forms (e. g. Mustelus and Eajidae) there is 

 said to be a single efferent duct and a single segment of the "cranial 

 zone" (E-edeke). 



