10 ON PARASITES. 



tises mucli among tlie common class of people will often find the 

 question of entozoa gravely mooted in his presence. In those palmy- 

 days of empiricism as soon as a child presented any of the incongru- 

 ous symptoms supposed to indicate the presence of these dire destroy- 

 ers of juvenile health and comfort, straightway, in the quaint 

 language of Kuchenmeister, "the time-honored worm medicine was 

 administered with one hand, under terror of the wholesome birch 

 wielded by the other." If the domestic remedies did not succeed in 

 expelling the unwelcome intruders, or in curing the cachexia upon 

 which they were supposed to depend, the family physician, or per- 

 haps some great specialist upon worms, was summoned, who skilfully 

 directing his medication to the supposed indications, either removed 

 the causative cachexia ; or, by a coup de inaitre, killed the entozoa 

 without injuring the living covers that they infested ; or, by altering 

 the character of the intestinal secretions, rendered them no longer 

 acceptable to their despoilers ; or, lastly, by such mechanical irri- 

 tants as the enema, drove the intruders out of the intestines. Often 

 after the administration of powerful drastic and chologogue cathar- 

 tics, the copious digestions of blood -altered bile, and intestinal 

 mucus, were triumphantly pointed to as the mangled remains of 

 animals, whose very presence was problematical. All this is happily 

 altered now. Although entozoa are as abundant as of yore, yet the 

 improved knowledge which present physicians possess of their patho- 

 logy and treatment, has greatly humanized this department of medi- 

 cine. To cause dangerous mucoenteritis in the expulsion of entozoa 

 would now be considered mal-practice. 



The wonderful discoveries that have been made by means of the 

 microscope among parasites infesting the human siibject constitute a 

 basis for startling speculation. Thus, diseases that used to be attri- 

 buted to other causes are now boldly referred to a parasitic origin, 

 although the parasites may not be discovered. The Cholera Asiatica 

 of the present century, the Black Death, and Sweating Sickness of 

 former periods, present many features and analogies favorable to this 

 supposition. The highect powers of the microscope have failed to 

 define the limits of vitality, so vastly minute are some of the animal- 

 cular inhabitants of the earth. Hence, although we should fail to 

 detect them, microscopic organisms may still be the cause of dis- 

 ease. Their presence in such a case would need to be determined by 

 negative evidence,— the diagnosis made by exclusion. The probabil- 



