left half of the vitellaria is characteristic for the species which is now 

 under consideration. They unite by means of a dorsal transversal 

 canal lying somewhat ahead of the anterior end of the ovary; with this 

 the right half of the vitellaria does not have efferent ducts^ which in 

 addition to it would have linked it with the rest of the female sex 

 system. This transversal vitelline duct descends on the ventral side 

 exteriorly from the left intestinal trunk and then opens into the ovi- 

 duct, receiving along the way, from the left half of the vitellaria, the vitelline 

 cells through several ducts which open into it in a rather short area 



extending from the transverse 

 duct up to the place of its con- 

 fluence with the "seminal 

 receptacles. " The repre- 

 sentation of the correlations 

 of the ducts is indicated in 

 Fig. 269 in which we see that 

 they are somewhat different 

 and more complex than 

 Brinkmann draws them 

 (Brinkmann, 1940, Fig. 7). 

 However, it is true that 

 such a thing is not observed 

 among other monogenetic 

 trematodes for whom the 



0.1mm 



Fig. 268. L/inguadactyla molvae 



Brinkmann, attaching disc of the 



worm from the gills of Molva dipterygia presence of differently located 



elongata (Otto) near the western shores efferent ducts of each half of 



the vitellaria, which then 

 merge and open into the oviduct 



of England {Atlantic Ocean). 



by a common duct, is characteristic. 



The second characteristic peculiar only for L. molvae is 

 the presence of 3 "seminal receptacles" and the peculiarities of 

 their structure. As has already been indicated, each of them opens by 

 a cluster of ducts on the anterior surface of the terminal part of the 

 vitelline duct forming 3 rounded sieve -like sections (Fig. 270). First 

 of all, similar sieves are absent in the sex systems of Monogenoidea 

 with the exception that the opening of the vaginas of Polystoma 

 integerrimum (and of close species/ also open outside by numerous 

 apertures. However, there are no bases to compare these two systems. 

 The function of these "seminal receptacles" is not clear. We cannot 

 consider them as real receptacula seminis because in the first place 

 they are relatively very small and in the second place none of the 

 Monogenoidea has them in such number and of such structure. It is 

 clear in the slides that a special tissue which has a peculiar glandular 

 (?) structure lies around each seminal receptacle of L. molvae. As 



419 



