PARASITOLOGY. 147 



under favorable conditions the larval form develops; 

 thus the sheep become infested through food and 

 water; the embryo may be carried by small streams 

 of water and thus spread contagion. 



Conditions Produced. — Seldom cause serious results, 

 but if found in large numbers they may cause con- 

 ditions similar to those caused by the Strongylus 

 Contortus, such as unthrifty coat, partial loss in wool 

 crop, diarrhoea, anemia, and if in sufficient numbers 

 emaciation and death. 



Treatment. — The same as for the Strongylus 

 Contortus. 



Uncinaria Canina (Canis — dog). 



Synonyms. — Uncinaria Trigonocephala. Dochmius 

 Trigonocephala. Anchylostoma Trigonocephala. 



Distribution. — Common in the United States, also 

 found in Europe. 



Description.— \\, has a thread-like body, white in 

 color; a large buccal cavity ; the mouth is provided 

 with six hook-like teeth ; by means of these booklets 

 it holds firmly to the mucous membrane and aided 

 by its strong muscular oesophagus draws blood; 

 they are still found attached to the mucous mem- 

 brane after death of the dog; the tail of the male 

 has a well developed caudal pouch ; the tail of the 

 female terminates in a sharp point ; the male is about 

 one-half inch long, the female three-fourths inch. 



Life History. — Same as the other species of the 

 Uncinaria. The methods of infestation aie the same. 



A?ii7nals Infested.— The dog, cat, and fox. 



Parts Infested.—SmoW and large intestines. 



Symi)toms —Vncindirio^is among the dogs is very 

 common ; it is more fatal among puppies than older 



