The Common Liver Entozoon of Cattle. 115 



THE COMMON LIVER ENTOZOON OF CATTLE. 



BY T. SPENCEE COBBOLD, M.D., F.L.S., 



Lecturer on Comparative Anatomy, Zoology, and Botany, at the Middlesex 



Hospital Medical College. 



If the attractive-looking amphistome, figured from Blanchard, 

 and described in the preceding number of this periodical, has 

 excited a desire for further information on " parasites not gene- 

 rally understood/' the writer is confident that the more fami- 

 liarly known creature whose portrait is annexed, will be found 

 worthy of the most attentive consideration. 



This little entozoon, more powerful for the destruction of its 

 friends than are our huge armaments for the annihilation of our 

 enemies, destroys in England alone some tens, and even hun- 

 dreds of thousands of sheep annually, besides afflicting in a 

 lesser degree the larger cattle;* added to which, our own 

 viscera are sometimes deemed worthy of a visit ; though, 

 happily, this is of extremely rare occurrence. Obviously, 

 therefore, the naturalist who shall be able to point out any 

 means whereby the ravages of the common liver fluke may be 

 frustrated, will confer a great boon on society at large, and 

 more especially on agriculturists and cattle-breeders, who are 

 most nearly interested in the welfare and preservation of their 

 flocks. 



On more than one occasion the writer has sought to convey 

 to the parties above mentioned accurate intelligence as to the 

 mode in which the liver flukes gain access to their hosts, or, in 

 other words, to the bodies of the herbivorous quadrupeds they 

 infest ; but, as happens too frequently in such cases, he has 

 found the vague opinions of a bygone age deemed more worthy 

 of credit than the clearly enunciated facts of recent scientific 

 discovery. When a still brighter light, however, shall have 

 brought to view all the missing links now wanting to complete 

 the chain of evidence, the promoters of science will more hope- 

 fully seek to enlighten those who, in so far as natural know- 

 ledge is concerned, are unwisely clinging to the " tales of a 

 grandfather." 



* Lest the writer may be thought to exaggerate the numbers here spoken of, he 

 begs to call attention to an extract from that trustworthy and admirably con- 

 ducted northern journal, the " Edinburgh Veterinary Eeview." At p. 63 of last 

 year's volume the following passage occurs: — "In England this scourge of the 

 ovine race has occasionally reduced the number of sheep so much as to materially 

 enhance the price of healthy animals. Eor instance, in the season of 1830-31, the 

 estimated deaths of sheep from rot was between 1,000,000 and 2,000,000. By 

 supplying turnip, oleaginous cakes, and grain, sheep partially affected can be fat- 

 tened ; and those not affected can be kept sound by a limited daily allowance of 

 one or other of these foods." Supposing the number to have been 1,500,000, this 

 would represent a sum of upwards of £4,000,000 ! 



