IXODES RICINUS : MANIPULATION 641 



be remembered, as Nuttall himself points out, that the data obtained from 

 the study of the life processes of ticks in the laboratory, where they are 

 kept apart from their true hosts and natural surroundings, are to a cer- 

 tain extent fallacious, the conditions being unusually favourable ; this, 

 however, in no way detracts from their value as a guide to the worker. 



Ceratixodes putus is parasitic on birds, and Nuttall found large 

 numbers in the nests of guillemonts in South Wales. The nests consist 



of hollows in caverns in precipitous cliffs and can 



Ceratixodes putus 

 only be reached from the brow of the cliff with the 



assistance of a rope. All the other stages except the unfed larvae were 

 found in the damp earth of the nest ; numbers of the unfed females were 

 encountered on the exposed rocks. Nuttall made numerous attempts to 

 feed the larvae, nymphs and unfed females on fowls, ducks and gulls, but 

 without success. It would appear that the ticks were placed on the 

 birds, the bare skin under the wing being the part selected ; it has often 

 been noted by the senior author that ticks which are placed directly on a 

 host take much longer to attach themselves than if they are placed in a 

 cage with a host or in a bag or cloth close to its body, and in some cases 

 fail to do so. The failure noted above may have to do with some 

 particular site at which the tick feeds. Nuttall's observations have, 

 however, demonstrated that C. putus requires three hosts, and that the 

 male never sucks blood, but after emerging from the nymphal stage 

 waits for the replete female, with which it immediately copulates ; all 

 the stages may live for long periods without food. 



Ixodes ricinus, the common cattle tick of Europe, has been bred 

 by Nuttall on cattle and rams. The larva remains attached from 4 to 10 



days on the calf ; the nymph 3 to 6 days on a ram and 



. Ixodes ricinus 



the adults 4 to 7 days on the same host. The period 



which elapsed before the eggs hatched was from 49 to 62 days and from 

 larva to nymph 124 days. Oviposition began from 17 to 24 days after 

 the females were full-fed and lasted from 32 to 45 days, the female laying 

 from 2,400 to 3,200 eggs. Females may survive ten days after oviposition 

 is complete. It is comparatively easy to manipulate this tick once the 

 larvae have been obtained. As the methods likely to be employed are 

 similar to those adopted in the case of other ticks of cattle they will be 

 dealt with full}- further on. The manipulation of Ixodes ricinus, for 

 instance, would be very similar to that of Rhipicephalus appendicitlatus 

 and R. simus. Ixodes hexagon us may be handled in the same way 

 as Rhipicephalus sanguine us and Haemaphysalis leach i. Had wen has 

 successively raised Ixodes angustus on the squirrel, Scuirus hudsonius 

 81 



