The Spinose E^ar-Tick. 653 



the back of a calf. The largest uumbei ol larvae seen together was 

 under the salt-trough in the calf camp. These larvae were very 

 active when disturbed, but they evinced no tendency to make for 

 Mr. Faure nor to get on to his hand, which he put on the ground a 

 few inches from them — they rather seemed to want to get out of the 

 sunliglit. It evidently does not take tlie larvae long to find the ears 

 and to settle down to feed. One calif that was born about 8 o'clock 

 in the morning was examined at m o'clock in the afternoon of the 

 next day, and already ten ]ar\^ae were seen to have started to feed in 

 its ears. 



Lonpevifij of flic Tick. — The unfed larvae appear to be short 

 lived compared with the larvae of Ixodid ticks. Most of those 

 hatched under casual observation at the Division's office have died 

 within a month. In the American account alluded to it is stated that 

 under favourable conditions they may live for eighty days, but there 

 is reason to assume few live as long as that, while Ixodid larvae live 

 far longer waiting ifor an animal. It follows that the chances are 

 very much against the very small larvae succeeding in getting on to 

 an animal in the open veld. Then while Ixodid ticks mate before 

 they feed up and the females are therefoit.' ready to lay eggs when 

 they drop, the females of the ear-ticks must find mates off the animal, 

 and hence the chances are heavily against the ear-ticks that aje 

 dropped in the open veld becoming mated. It is for these reasons 

 that the ear-tick is far more common in kraaled stock than in animals 

 that roam at large in the veld day and night. 



The female ear-tick does not lay her eggs until she has mated, 

 and she seems able to wait a very long time for a mate. Under date 

 of 10th January, 1919, a nymphal tick taken from the ear of a man 

 at Capetown was sent to the Division. In a few days it morlted and 

 proved to be a female. It was kept alone in a glass cube until 25th 

 November, or for nearly eleven months after it would have mated had 

 it had an opportunity. A male that had shed its nymphal skin on 

 20th November was then placed in the tube, and a few days later, on 

 the 29th, the two ticks were seen to be together. Eight days later, 

 6th December, the female hegan busily to lay eggs. The American 

 bulletin referred to ahove tells of one unmated female that remained 

 alive for eighteen months Mr. Faure has had one female live still 

 longer. It was one of a number of specimens confined together in a 

 small box, and it was seen to be alive twenty-two mouths from the 

 iime it was taken from the ear. Whether it mated and laid eggs or 

 not is unknown. The ear-ticks do not lay all their eggs at once, 

 another respect in which they differ radically from Ixodid ticks, but 

 lay intermittently for months. The American bulletin states that one 

 female, given a mate as soon as she had moulted the nymphal skin, 

 did not finally cease laying until 191 days from the moult; she had 

 spread the laying of her eggs over six months. These facts are of 

 interest because they indicate how infection might be kept up on a 

 farm even were remedial and preventive measures that effectively 

 prevented the maturing of any ticks and the introduction o^f any fresh 

 infection kept up for a full year or even nearly two years. A few 

 treatments in summer, as recommended by Mr. Story, however, should 

 show a marked diminution in the severity of the pest ; and it stands 

 to reason that in the construction of new kraals and sheds, and in the 



