90 IOWA ACADEMY OF SCIENCES. 



38. Amarantus retrojiexus. 



39. Amarantus albus. 



40. Amarantios bliioides. 



41. Chenopodmm album (without utricle). 



42. Polygonum persicaria. 



43. Polygomim hydropiper. 



44. Polygonum aviculare. 

 45.' Polygonum acre. 



46. Polygonum convolvulus. 



47. Rumex acetosella. 



48. Anthenus coiula. 



49. Ambrosia artemisice folia (with utricle). 



50. Eumex crispus. 



51. Ambrosia artemisicefolia (naked). 



52. Verbenia bracteosa. 



53. Chrysanthemum leucanthemuvi. 



54. Polygonum convolvulus (enlarged three times). 



55. Ambrosia artemisice/olia (enlarged, with involucr( 



PRELIMINARY OBSERVATIONS ON A CATTLE DISEASE FREQUENTLY 

 OCCURRING IN IOWA. 



BY W. B. NILES. 



This disease is called hydrophobia by the people at large in a majority of cases. 

 By veterinarians it is diagnosed as rabies, cerebro-meningritis, enteritis and im- 

 paction of the third stomach. 



As regards its distribution, it may be said to occur most frequently north of a 

 line drawn east and west separating the State into halves. In the extreme south- 

 ern part cases are rarely reported. 



Nature, Symptoms and Course of the Disease. — In some outbreaks the nattle are 

 reported to have been bitten by a dog, but seldom has the owner been able to posi- 

 tively say that such is the case. In a majority of cases no dog is mentioned in 

 connection with them, and no strangely acting dog has been reported in the neigh- 

 borhood. 



In all outbreaks the disease runs a lingering course in the herd. Several cases 

 occur and the time elapsing between the first and last case extends over several 

 ■weeks; in some outbreaks over five or six months. The symptoms observed in the 

 different outbreaks are very uniform. So uniform that it is easy in most instances 

 to recognize the trouble from descriptions written by the owner of the cattle. 



At first the animal appears^uneasy. is alert, taking more notice than common of 

 everything taking place about it, is very attentive if a strange man or dog appears, 

 and a slight switching of the tail is often observed. The eyes soon become staring 

 and wild, and eventually reddened. The animal early refuses food and drink, and 

 as a consequence becomes very gaunt in appearance. Early in the course of the 



