153 



A Further Note on Ixobfs heduvius (Lim-N.). 

 By E. T. Lewis, F.R.M.S. 



(EeadJune 21st, 1901.) 



Members of the Club who were present at the meethig of 

 June 15th, 1900, will probably remember that a paper was then 

 read in which details were given of some observations which 

 tended to show that impregnation in certain species of ticks was 

 performed by means of the mouth organs of the males. Living 

 specimens in copula in the manner described w^ere exhibited in 

 the room on that occasion, and the paper itself was published in 

 November last, with a plate in illustration (see Journ. Q. M. (7., 

 Vol. vii., p. 381, PI. XXL). Although there seemed a strong 

 probability that the inference drawn from these observations was 

 correct, it was admitted that the one conclusive proof — namely, 

 the fact of the transference of spermatozoa — was missing, and 

 that until this was demonstrated it would be unwise to affirm 

 that what had been seen was the actual method of impregnation, 

 although a good case had been made out for supposing it to be 

 so. It is therefore a matter of great satisfaction to be able to 

 announce that Mr. Wheler has now settled this question beyond 

 doubt. Writing to me under date of May 18th, 1901, he says : 



" I am sure it will interest you to hear that I believe I have 

 been able to prove beyond doubt the accuracy of your views on 

 the sexual intercourse of Ixodes reduvius by the mouth oigans, 

 as communicated to the Quekett Microscopiccd Club Journal in 

 November last. 



" I was examining some of these ticks for another purpose, 

 when I accidentally found the spermatozoa of the male. These 

 were easily obtained by severing the capitulum from the body, 

 and the spermatozoa were plentiful in the tissues which were 

 pressed out by crushing the body on a cover glass. I found no 

 spermatozoa in a number of females taken from diseased sheep 

 which I examined. 



" Yesterday I took three fasting females (these are sure to 

 be virgins) and three males on rushes. They soon paired in the 



