CESTODES 



261 



capsules we have the cellular layer external just the reverse of the mother cyst. 

 Scolices may develop either on the outside or inside of these brood capsules. It is 

 interesting to note that one onchosphere may develop hundreds of scolices. From 

 the parenchymatous layer of the mother cyst, daughter cysts are formed; these have 

 an external stratified layer and an internal parenchymatous one; within them a vary- 

 ing number of scolices may develop. From these daughter cysts, granddaughter 

 cysts may arise all within the mother cyst and hence are termed endogenous. 



At times the daughter cysts work their way external to the mother cyst and pro- 

 ceed to develop in a manner similar to the endogenous formation. The exogenous 



Ova or the Parasitic Worms or Man 

 CESTODA 



DRAWN TO SCALE X . I <S O O 



Tivniix 

 solium 



n Diplo^a^ Dibothrio^ 



cfonoporus cephalus nymenolepis ntxna. 



^m^ 3 f*r>cJ*^r*ln 1*>\tlIS/ \ te.rtcrRon8Qm,froBSt.tlc!9(O) 



/?%v dr&nais. iuius(*rten,o<m.>) 



If 'l)\m O (after Ioo.l$a6) . _,=- -1 t ' 



s^^\nymenolepi 



iw^^%^r ^x \ diminuta 



TeemaXgp^ f%\ \^^^ fn >.^^^ 



sadinata . 



OM'f'i-^'iow) T\- i- i 



Uipylidium 



num^mrs.^iooo) 



Cestode sepments 



DRAWN TO SCALt X IO W 



ggjj^^jgj ^^MauMtTciy, 



Decvtvinea 



Eni njL, SSL- *"!fc 



solium eaninum Dibothriocephalus latus s 



m*/"" (/.S.A'tu-atMedicaJ School. 



FIG. 71. Cestode ova. 



development is rare in man, but common in hogs. Hydatids containing no scolices 

 are called sterile. These cysts may be as large as a child's head, but are usually 

 smaller. The fluid of these cysts contains about i% of NaCl, also a trace of sugar; 

 in addition there is a toxin which produces urticaria and acts as a cardiac depressant. 

 If any quantity should escape into the peritoneal cavity at operation, it may cause 

 death. Hydatids develop very slowly, and the duration of the disease is usually 

 from two to eight years. 



Echinococcus multilocularis is possibly due to a species different from T. echino- 

 coccus. In this we have a honeycomb arrangement with cavities filled with a gela- 



