174 ENTOZOA. 



In tliis attitude only can we ultimately hope to acMeve a certain 

 knowledge of tlie means of preventing, if not of entirely eradicating, 

 this fearful disease ; and the writer confesses that it seems to him 

 strange that the cost of these necessary experiments should 

 hitherto, in this country at least, have exclusively rested with 

 those who have given much time, aided by such talents as they 

 may possess, to practically scientific inquiries. On independent 

 grounds he has himself, year by year, sought to throw hght upon 

 the origin and development of the various internal parasites which 

 either annoy or destroy our valuable animals ; and as, in some 

 instances, these experiments have proved eminently instructive, he 

 cannot avoid expressing his thanks to the Association which has 

 aided him in these inquiries.* 



Those who desire to know what has been doing in other lands 

 towards the elucidation of this important subject should, in par- 

 ticular, consult Davaine and Leuckart's works, already quoted, as 

 well as the Treatise, " De la Reproduction chez les Trematodes 

 endo-parasites," par J. J. Moulinie. "Extrait du Tome III. des 

 Memoires de I'lnstitut Genevois ;" and also the excellent helmin- 

 thological memoir by Dr. H. A. Pagenstecher, of Heidelberg, 

 entitled " Trematodenlarven und Trematoden," at the close of 

 which the author appends a note referring to the work of 

 Moulinie, finally adding, "We are encouraged again to take up 

 our hitherto fruitless searchings among land-snails, and we hope, 

 with M. Moulinie, that the next steps in this direction will clear 

 up the history of the development of Distoma hepaticum." In this 

 desire I heartily concur. 



Symjjtoms 'produced hy the Bot. — When the disease has far 

 advanced, it is easy to know a rotten sheep, not only by its very 

 look, but still more convincingly, as I have myself frequently 

 tested, by slightly pressing the hand over the region of the loins. 

 In this region the diseased animal is particularly weak, and the 



* See " Report of British Association " for 1862. 



