SCIENCE-GOSSIP. 



7 



are shown by Fig. 5, representing the larva, pupa, 

 male, and female of /. reduvius, magnified about six 

 diameters. None of these are distended specimens. 



Some females of /. phimbeus were taken, fully 

 distended, from a dog on July isth. On August 

 4th, twenty days after, one of them commenced 

 to lay eggs, some 100 to 200 in number, under the 

 roots of damp moss. The eggs were oval, about 

 0.50 mm. in length, and 0.40 mm. in breadth. The 

 fcmnle parent remained with them till August 26th, 

 and ilied on September 27th. The eggs hatched 

 on October 9th, having been nine weeks and three 

 days incubating. A large proportion of the 

 females taken were damaged 

 by having the rostra mutila- 

 ted by removal from the 

 host. These lived for some 

 time, but never survived the 

 process of laying their eggs, 

 which, moreover, were sterile. 



No difficulty has been ex- 

 perienced in keeping alive 

 ticks of all stages of growth, 

 for lengthened periods, in 

 glass bottles with a little 

 damp sand and moss, but 

 development has not been 

 obser\-ed to take place under 

 such conditions. If kept 

 without moisture they soon 

 die, but several degrees of 

 frost appeared to have no 

 effect upon adult females. 



On September 3rd, a hot 

 and fine day, large numbers 

 of larvae pupae, and adults 

 of both sexes of /. reduviits 

 were found with a sweep n^t 

 on a patch of rushes. Tvi'O 

 pairs of the latter paired in 

 the bottles immediately after 

 capture. On September 26th 

 twenty-six females and seven 

 males were taken from a deer 

 in Alnwick Park, and a 

 largely distended female was 

 impregnated by a male 

 after removal. No ticks 

 were found on a deer 

 killed the previous day in an adjoining paddock. 



The colour of ticks, being partially due to the 

 contents of the intestines, is decidedly variable. 

 MarJiings which are pronounced in some un- 

 distended specimens, are lost very soon after 

 death. During the process of distension consider- 

 able changes also take place. The intestinal 

 markings, if any, quickly disappear as it pro- 

 gresses, and when nearly complete a more or less 

 uniform colour pervades the whole body. Thus, 

 slightly distended specimens of the larvae, pupae, 

 and adult females of /. hcxagomts and /. phttuhcits 



Sniiiip Ticks, 



are of a pale drub, changing on fuller ilistensiou to 

 a dark blue. Adult females of /. reduviiis 

 change from red to nearly pure white. Under 

 these circumstances, descriptions are apt to be 

 very misleading, unless allowance be made for the 

 amount of development to which the tick has attained. 

 The object of writing these notes is to call atten- 

 tion to an important but neglected subject, with 

 the hope that others may be induced to study the 

 habits of these pests. The importance of the ques- 

 tion is exemplified by the fact that in one spring, 

 no less than Soo sheep were lost on one hill farm 

 by Louping-Ill, and where it is prevalent, certain 

 loss is annually incurred. 



Nothing is more inexplic- 

 able than the conditions un- 

 der which animals are, or are 

 not, subject to the attacks of 

 the ticks. Sheep on the 

 hills are evidently ver}' sus- 

 ceptible, when impoverished 

 by the hardship of winter, 

 and the strain on the system 

 caused by the lambing time. 

 On low ground the sheep 

 appear to escape the attack 

 of ticks altogether, though 

 they may be common on 

 other animals. This is anal- 

 agous to the fact mentioned 

 by Mr. Barber in "Nature" 

 (June, 1895), that in Antigua 

 ticks leave infested cattle 

 when they are changed to a 

 belter pasture. On the 

 other hand, I am unable to 

 gather that the poorer sheep 

 on the hills are more suscept- 

 ible than those in better condi^ 

 tion ; but have been in- 

 formed that the contrary 

 is to some extent the case. 

 It is, however, among sheep 

 freshly imported on to 

 "foul" ground that the 

 greatest mortality takes 

 place. A satisfactory ex- 

 planation of an immunity, 

 which does not seem to 

 depend altogether on the condition of the animal, 

 might go far towards suggesting the direction that 

 experiments should take with a view of minimising 

 the evil. 



[Mr. Wheler would be much obliged if corre- 

 spondents would favour him with specimens, living 

 preferred, of any other British species of the genus 

 Ixodes, with particulars of the circumstances under 

 which thev were found. His address is Swansfield 

 House, Alnwick.] — Ed. .S. G. 



(To I'C continued ) 



