217] PROTEOCEPHALIDAE—LA RUE 217 



position anterior to the cirrus-pouch it never crosses the latter but 

 passes beyond it and then dips down below the coils of the vas deferens. 

 In many mature proglottids the initial part of the vagina is greatly 

 dilated and this dilatation extends for some distance down the length 

 of the vagina. There are no coils of the vagina anterior to the ovary 

 but it may lie in sinuous curves. A weak sphincter vaginae close to the 

 external opening and a small receptaculum seminis near the mid-piece 

 of the ovary are present. The ovary varies in shape with the state of 

 contraction of the proglottid. It is always thin and flat and is made up 

 of anastomosing tubules as in 0. filaroides. In very broad but short 

 proglottids the lobes of the ovary are long slender wedge-shaped struc- 

 tures the apices of which lie in the mid-field of the proglottid. In 

 attenuated proglottids the lobes are much shortened and broader than 

 in long proglottids, in which case the ovary may be distinctly alate in 

 form. The organs of the interovarial space are arranged about as 

 delineated for 0. filaroides (Fig. 104). The vitellaria are lateral, com- 

 posed of medium-sized sparse follicles. Since no ripe proglottids have 

 been seen a well developed uterus cannot be described. In one proglot- 

 tid in which a few eggs had been passed into the uterus there were 

 from 25 to 40 lateral pouches on either side. No uterine pores have 

 been observed. No eggs with developed embryos could be found. A few 

 eggs which could be but poorly seen within the uterus of a toto prepara- 

 tion showed yolk-masses measuring 0.010-0.012 mm. in diameter. The 

 egg membranes could not be measured. Fuhrmann saw no eggs. 



This species tho most closely related to 0. filariodes can be readily 

 distinguished from the latter by its larger strobila, larger head, larger 

 suckers and larger testes. The excretory vessels are spiral structures 

 in 0. lonnbergii but straight in 0. filaroides. The ovarian lobes are 

 also different in size and shape. 0. lonnbergii differs from the Ophio- 

 taenia parasitic in snakes by the position of its genital pore and by 

 the less muscular character of its cirrus. Its ovary is also of a different 

 shape. The position of the excretory ducts is much farther mesad in 

 0. lonnbergii than in any species of Ophiotaenia at present known from 

 snakes. 



While further investigation may prove that the species of Proteo- 

 eephalids infesting Amphibia are generically different from the species 

 infesting snakes there is at present no justification in erecting a new 

 genus for them. Their nearest allies are among the Ophiotaenia, hence 

 the writer places them in that genus. 



