50. 



net enough room for the total number of spines en the adult 

 collar when compared with the increase in sis5 of the collar 

 of the adult over the ceremria. The col In r ol the o^roaria 

 measures about 0*16 rara* in diajea >t >r while the collar of 

 the mdu.lt measure* but, 0.496 mm* Since th/: collar spines 

 of the adult are about five and a half timer* larger tnan 

 the collar spines of the oerearia, r*nd the sire cf the 

 collar hate not increased quite four times, it is obvious 

 th^re would hardly bo gnougfr room for the full forty three 

 on the adult* *hi8 i(i-i is further supported "by the faot 

 that the spines are arranged quite closely together on the 

 ee*aaria< 



w 



The body spines of the adult ire muoh like those of 

 the oeroaria (fig 45) but have increased about four times 

 in si^e, those on the wide between the oral and ventral 

 suckers measuring 00&t> ram in length* The arrangement of 

 the body spines is about the eame alt?o* Vent rally, between 

 the oral and ventral suoVers, the opines almost completely 

 cover th^body* On the sides ut the ventral tucVer blunt, 

 irregularly arranged spines wero also found* 



The great increase of the size of the ventral pua>*r 

 is an outstanding fact* In the oerearia it is 0*094 mm* 

 in diameter where is in the adult n 8 to 10 am* long it 

 javer -ige about 1*075 mm* in diaaeter. The size of the oral 

 sucker has inore&eed on the oeroaria only from 0.072 to 

 270 mm* This points tc the fact that Uie ventral sucVer 

 in the adult plays a very important function in attachment* 



the distance between the onl an<i ventral suo>ere in 

 Uie adult is about l*0b mm*, whereas in the- oercaria it is 

 about 0*02.3 nun* This is a gain of less than four and a half 



