392 Recent Discoveries in Entozoology. 



secondary causes concerned in its production. For our part, 

 however, we prefer to read His guidings differently, to sound 

 the aforesaid causes to their lowest depths, to search out the 

 animal parasite which thus afflicts mankind, to subject the little 

 beast to microscopic examination, to watch its growth and 

 development, to work out its anatomy, to study its haunts and 

 habits, to make it the source of a series of experiments ; in 

 short, to leave no stone unturned by which we may arrive at a 

 sound conclusion as to the best methods of checking its 

 abundance, and of preventing its destructive assaults upon the 

 welfare of our fellow men. An enlightened public will eventually 

 applaud these efforts j but, as in a crowd, it is only the tallest 

 men who see furthest, so, unfortunately, does it happen that 

 our laborious, self-denying, experimental physiologists gain 

 only the respect of the few ; whilst the many, unenlightened, 

 prefer the " old paths," not unfrequently, indeed, placing 

 every obstacle they can in the way of those who silently devote 

 their time and talents to studies which are calculated to benefit 

 us all. If it were necessary to exemplify the truth of these 

 remarks, we should refer to the recent attacks made upon 

 experimental physiologists in reference to the question of vivi- 

 section, and other investigations, demanding the destruction of 

 the lower animals. 



One-sixth of the annual deaths among the population in 

 Iceland are solely owing to the Echinococcus entozoon, and 

 shall we therefore refuse to permit the helminthologist to con- 

 tinue his experimental inquiries on the score of cruelty to 

 animals ? As a shrewd writer in the pages of the Examiner has 

 recently very justly remarked, we have now arrived at a time 

 when " every abomination has its zealous and thorough-going 

 advocate/' 



The little entozoon producing the disease referred to Las 

 this singular peculiarity about it, namely, that in the adult or 

 mature condition it scarcely attains a length of one-sixth of 

 an inch, whilst in the larval, imperfectly developed, or so called 

 hydatid condition, it may grow to the size of a man's hat. In 

 the adult state it is a minute tapeworm, with four joints, and 

 a single head, armed with four suckers, and a double crown 

 of hooks ; whereas, in the larval condition, it presents an aspect 

 not unlike those toy air-balls which children play with. This 

 globular hydatid is furnished with hundreds, nay thousands, 

 of heads, each one of which is capable, under favourable cir- 

 cumstances, of becoming a tapeworm. The adult worm, as 

 we have said, lives in the intestines of the dog, whilst the 

 death-producing Larva infests man and herbivorous animals 

 of the domesl icated kind. 



To render our description more suggestive, we beg to direct 



