of view in the sense that in this case there is no doubt of the presence of a 

 special musculature, even though it is in part of the thorns, i.e., --a 

 considerable similarity in structure with the thorns of the covering of the 

 Gy rocotylidae . 



During further research on the structure of Capsalinae,we 

 noticed that the ovary in these worms, at any rate among representatives 

 of the genus Tristoma, is not at all a simple formation but consists of a 

 number of independent folliculi each opening by an independent duct into a 

 special chamber located near the anterior edge of the entire complex (Fig. 314). 



0.5HH 



Fig. 314. Tristoma coccineum Cuvier, the ovary of the worm from the 

 gills of Xiphias sp. from the region of the Island of Madeira (Atlantic Ocean). 



The ovary, both in Loimoidae (see page 415 ) and Chimaericolidae (see page 

 415 ), has, according to the newest data, a follicular structure. Thus, among 

 Monogenoidea this type of ovary is distributed in a number of groups very 

 distant from each other. The structure of the ovary of such a type resembles 

 very closely that which exists in Gyrocotylidae and Cestoidea s. str. In 

 addition to that, the presence of a special chamber in Tristoma, about which 

 we have just spoken, is very sinnilar to the ovifunnel of tapeworms. In con- 

 clusion the sharpest difference between Monogenoidea and Cestoidea, about 

 which we have written, is considerably reduced and cannot be considered as 

 very meaningful. One should not attach great significance to the differences 

 in the location of the sex apertures, for in monogenetic trematodes we can 

 cite at the present time a number of examples of considerable variability of p. 476 

 the relations between the male sex opening and the openings of the uterus and 

 the vagina. Thus, among many Capsalidae the rapproachement of all three 

 sex apertures cakes place. In Anthocotylidae the opening of the uterus lies on 

 the side of the body and the male sex aperture on the ventral side along the 

 medial line. Among certain highest Oligonchoinea there are also analogous 

 relations and the atrium, which is common for all three apertures, is 

 encountered in a number of the highest and lowest Monogenoidea. The 



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