CYSTICERCUS CELLULOSE 251 



dogs, (2) exclusion of dogs from shores of lakes or reservoirs from 

 which drinking water is taken, (3) extreme cleanHness in handling 

 of food, (4) prevention of dogs from eating the entrails or meat 

 scraps of animals which may be infected with hydatids. 



Cysticercus of Teenia solium. — The fact that the bladder- 

 worms of the pork tapeworm, Teenia solium, sometimes occur in 

 man has already been mentioned. Since self-infection with the 

 eggs of the worm is a dangerous possibility, the presence of a 

 pork tapeworm in the intestine is to be looked upon much more 

 seriously than infection with other tapeworms. 



The bladderworms, technically named Cysticercus cellulosce 

 (Fig. 86A), develop from the six-hooked embryos which are 

 freed from the enclosing egg-shell by the gastric juices. The 

 embryos bore through the intestinal wall and migrate to various 

 organs and tissues to develop. 



The effect of Cysticercus infection depends entirely upon the 

 number present and upon their location in the body. A few of 

 them in the muscles or in the connective tissue under the skin are 

 quite harmless. In the eye, heart, spinal cord, brain or other deli- 

 cate organs their presence may be very serious, the symptoms 

 being due chiefly to mechanical injury. Infection of the brain 

 is usually accompanied by epileptic fits, convulsions and other 

 nervous disorders. There is no treatment except a surgical 

 operation, and this is often obviously impossible, both on account 

 of the number and position of the parasites. Moreover, in a 

 great many cases a correct diagnosis of this infection is made only 

 in a post-mortem examination. 



Sparganum. — The group name Sparganum has been given to 

 plerocercoid larvje of tapeworms of the family Dibothriocephalidse, 

 of which the adult form is unknown and the true genus there- 

 fore indeterminable. 



The most common type of such tapeworm larvee is Sparganum 

 mansoni (Fig. 98), a long, elastic rubber-like worm, varying 

 from about three to 14 inches in length. It is not segmented 

 but is transversely wrinkled so that a superficial glance gives one 

 the impression of a segmented worm. At the broader anterior 

 end there is a small conical projection on which is found the 

 scolex, somewhat invaginated. These parasites are found ir- 

 regularly coiled in the connective tissues of the body, often under 

 the lining of the body cavity, sometimes in the vicinity of the 



