ON SOME ANIMAL PARASITES IN BRITISH GUIANA. 183 



Class ACANTHOCEPHALA. 



Echinorynchis gigas, Goeze. This appears to be a common inhabitant of the small 

 intestine of pigs in British Guiana ; numerous specimens have, on various occasions, 

 been obtained from pigs slaughtered at the Georgetown Abattoir. 



Class ARACHNIDA. 

 Order ACARINA. 

 Family Ixodidae. 



In British Guiana all kinds of hve-stock are attacked by various species of ticks, 

 which are in many cases directly responsible for a very considerable annual financial 

 loss. Preventive measures, such as dipping, are quite unheard of and the presence 

 of these pests is universally regarded \\ath the utmost indifference. 



Argas j^ersicus, Wald. This tick is a common inhabitant of fowl-houses throughout 

 the Colony, and the larvae are to be found on most varieties of poultry. The larval 

 stage of this tick is known locally as " Nimbles." 



Rkipicephalus sanguineus, Latr. One of the commonest external parasite of dogs. 

 All stages of development may be found on this animal. Between the digits and 

 within the ears are favourite points of attachment. 



Margarojjus anmdatus var. australis, Fuller. Flourishes on all kinds of cattle. 

 Steers that have been in the pastures for a few months soon become heavily infested 

 and thereby loose weight and condition. Instances have been observed where several 

 ticks have attached themselves to the eyehds and engorging there caused intense 

 irritation. The death of a calf through tick infestation is not uncommon. The 

 institution of properly constructed dipping or spraying contrivances would hand- 

 somely repay the initial outlay. This tick has a number of other hosts, including 

 the common toad or " Crapaud " {Bufo marinus). 



Amhlyomma cajennense, F. Locally known as the Balata Tick. In certain districts 

 of the coast-lands, usually near the rivers or creeks and also within the forest area, 

 this tick is commonly met with as a parasite of man. In these infested areas after 

 traversing but a few miles as many as a dozen of these ticks will often be foimd 

 attached to different parts of the body. Unless carefully removed an irritating spot 

 is left which will prove troublesome for some months. 



Amhlyomma humerale, Koch. This tick has been twice taken from turtles and on 

 both occasions some distance inland. The points of attachment are the softer and 

 unarmoured parts of the head and neck, especially about the eyes and mouth. Some 

 24 specimens were taken from a single turtle. 



Amhlyomma dissimile, Koch. This species is a common parasite of cold-blooded 

 animals, such as toads, lizards, and many varieties of snakes. It is widely distributed. 

 The ordinary toad {Bufo marinus) invariably bears several specimens attached to the 

 head immediately between the eyes and occasionally on the back. These ticks are 

 especially numerous after the heavy rainy seasons in January and usually again in 

 May. A single engorged specimen fully half-inch in diameter was on one occasion 

 taken from a Salampenta {Turpinamhis nigropunctatm). We have also taken this 

 species from the Iguar.a {Iguana tuberculata). 



