228 ANIMAL PARASITES. 



ties may be generally favorable to tbe introduction of the eggs of 

 the Taenia in question into the stomach, and that, on the other 

 hand, it is a general observation that certain Cestodea frequently 

 have a very limited habitat. 



The duration of the life of the Echinococci does not appear to 

 be very short. According to Eschricht, one patient must have 

 borne his colony eighteen years. 



The prognosis of the Echinococci varies according to the situa- 

 tion of the swelling, the accessibility of the organ attacked for 

 operation, and according to the primary or secondary injury to 

 important organs and the whole system ; but the prognosis is 

 more favorable than is generally supposed. The tumours, when 

 they are accessible, are amongst the number of curable tumours; 

 they may cure themselves by bursting, and when they are once 

 got rid of, relapses in the same colony are rare and exceptional 

 cases, and every new Echinococcus produced usually owes its 

 existence to a new immigration of embryos. But for this very 

 reason the continuance of the mode of life in endemically 

 affected places furnishes a more unfavorable prognosis. The 

 natural cure by the bursting of the colony and the passage 

 of daughter-vesicles may be accompanied by symptoms dan- 

 gerous to life, or, if it takes place in the direction of the 

 larger bronchi, by difficulty of breathing, or may even lead to 

 actual suffocation. 



The therapeutics in this case are prophylactic and direct. 

 The prophylactic agree with those of the other cystic Avorms, 

 but, as the Tania belonging to it, and its host, are still unknown, 

 we can only give indications, which I shall detail in a separate 

 Appendix of " Reflections on the endemic occurrence of the 

 Echinococci in Iceland." 



The direct therapeutics lie entirely in the province of surgery. 

 The reader may consult surgical manuals for the treatment of 

 innoxious, sacculated swellings, according to their various posi- 

 tions. We must attempt to get rid of the accessible ones either 

 by the galvanic acupuncture, by incision or puncture, employing 

 the necessary surgical precautions; in other respects all internal 

 treatment and every cure with ointments or salves are to 

 be avoided, let them bear what name they will. What is the use 

 of the treatment with iodide of potassium, or the rubbing in of 

 mercurial ointments ? In the most favorable cases the worm may 

 perhaps be destroyed and die. But what is gained by this, when 



