64 AVIAN CESTODES, 



the same level as tlie lower series of testes. The organ is also 

 seen to be made up of relatively large rounded masses of yolk- 

 matter. The duct passes directly dorsally and anteriorly, to 

 enter the fertilising duct at the shell-gland complex. 



Tins latter complex lies, in the form of a rosette, in the mid- 

 line between the vitellarium and the ovarian briHge, its tliameter 

 being about 0-04 mm. In section the shell-gland is seen to 

 border on the dorsal transverse muscle-fibres. Thus it lies 

 dorsally to the plane of tlie ovarian bridge. The component cells 

 are long and club.shaped, the broad rounded portion containing 

 the nucleus embedded in granular protoplasm. A nucleolus is 

 present. The remainder of the cell is long and narrow, serving 

 as a duct. These cells nre about 0-018 mm. long. They cover 

 the walls of the fertilising duct for a very short distance. This 

 duct penetrates the complex from its dorsal side. 



The vagina opens externally, just behind and slightly below 

 the cirrus-sac. It then travels inwards and slightly backwards 

 as a narrow well-defined tube. Just after it passes over the 

 excretory vessel of the corresponding side, it commences to widen 

 o-radually to form an elongate spindle-shaped, thin-walled recep- 

 taculum seminis, which narrows again as it approaches tlie ovarian 

 bridge. Occasionally the leceptaculum is more rounded on 

 account of the contained mass of spermatozoa. 8oon after pass- 

 ino- below the ovary (between it and the vas deferens) the vagina 

 or more correctly the fertilising duct, receives the oviduct; and 

 then, after a very short course, passes downwards to enter the 

 shell-gland complex. It is here that the vitelline duct joins in. 

 Nothing of the nature of a swallowing apparatus was detected. 



Situated on the walls of the vagina, in the neighbourhood of 

 the excretory vessel, just where the receptaculum begins, and 

 extending outwardly for about 0*05 mm., is a mass of unicellular 

 "•lands. Each gland-cell is somewhat flask-shaped, tlie large, 

 rounded end being nearer the middle of the segment; while the 

 narrow end, which serves as a duct, is directed outwardly. Thus 

 each cell is ol)li<iuely placed. The protoplasm is finely granular 

 and homogeneous, the nucleus being large, rounded, not readily 



