TYPES OF SPECIES OF CESTODA KKKKi I. O 



Behind tlie scolex the strobila gradually widens until at 033 

 mm. from the anterior end, that is at the point where segment- 

 ation becomes recognisable, the breadth is ahout 0055 mm. 

 The segments are here very narrow. Then there is a sudden 

 increase in breadth though the proglottids still remain very 

 narrow. Throughout the greater part of the strobila the width 

 is short, seven or eight mm., though occasionally it reaches ten 

 mm., the mature segments being from 0-7 to 1*3 mm. in length 

 (average ahout one mm.) Segments 3 - 8 mm. broad by 07 mm. 

 long were seen containing ripe eggs. 



The genital papilla is more or less prominent according as the 

 cirrus is everted or not. It is located just anteriorly to the 

 middle of the edge of each segment. The genital cloaca is some- 

 what elongate. The female opening is either immediately anterior 

 to or beside the male opening, though at times it was seen to be 

 below it. 



The excretory system consists of the usual two pairs of trunks, 

 an outer and an inner lying close beside it, the outer being very 

 much the larger, having a lumen of from 001 to 002 mm. in 

 transverse section. In cases where the diameter is less than this 

 the margin is usually very much crinkled. Lying just internally 

 to each outer tube is a very much smaller inner vessel with a 

 lumen of only 0-004 mm. The parenchyma surrounding both and 

 especially the inner vessel was deeply staining and contained 

 abundance of nuclei. Both vessels lie at a considerable distance 

 inwards from each lateral margin. They are situated in the 

 medulla at ahout equal distances from the dorsal and ventral 

 surfaces, but where the genital ducts cross over them, they 

 become displaced ventrally. Transverse excretory vessels are 

 absent. 



The nervous system is composed of a number of longitudinal 

 cords along each side as well as ring commissural nerves con- 

 necting the lateral cords of one side with those of the other. 

 There are three nerves laterally, a median or main trunk and 

 two accessory nerves, one slightly dorsal ly and one slightly ven- 

 trally. All three are connected by fibres. At certain levels 

 and especially near the posterior end of each segment large 

 paired nerves are given off dorsally and ventrally. These pass 

 through the cortex to meet with similar structures from the 

 other side to form ring commissures. The anterior commissural 

 ring is much less evident. From the same point of origin as 

 these ring nerves there are given off short but thick fibres lateral- 

 ly.- The main longitudinal fibres lie ventrally to the genital ducts 

 and the uterus. On the nerve ring in the neighbourhood of the 



