I04 



HARD WICKE 'S S CIENCE - G O SSIP. 



THE BLYBOROUGH TICK. 



{Aj-gas Fischcrii.) 



THIS interesting and curious arachnid was found 

 in considerable numbers during the removal of 

 the old roof from the village church at Blyborough, 

 near Kirton-in-Lindsey, Lincolnshire ; it forms a very 

 beautiful object for the lower powers of the micro- 

 scope. When living, the vermicular movements in 

 the coeca, which occupy nearly the whole of its body, 

 can be very distinctly seen. The cceca are well shown 

 in the diagram. Mr. Ball's drawing (fig. 85) is 

 taken from a mounted mature specimen, and shows 

 eggs in its interior ; but the anus, which is situated 

 very neaidy in the centre of the abdomen, is not shown, 

 nor are the spiracles (which are two in number, and 

 situated between the third and fourth legs on either 

 side) to be seen. Like its near relation, Argas re- 

 jlexns, which was found in Canterbury Cathedral, it 

 is very tenacious of life ; I have some at this present 

 time which appear to be as lively as ever, and have 

 been about five months in a glass-topped box, with 

 nothing but two small pieces of wood for them to 

 crawl upon ; I cannot see that they have altered in 

 appearance during the whole of that time. They differ 

 greatly from Argas rcflexiis in colour, shape, size, 

 and deportment ; thus, Argas rcjlcxiis is slate-coloured, 

 oval, three-tenths of an inch long, by nearly one-fifth 

 broad, whilst Argas Fischa-ii is of a beautiful red- 

 brown colour, nearly circular, and the finest speci- 

 mens do not reach one-fifth of an inch in their largest 

 diameter ; as to their deportment, if you \.o^xQ\\ Argas 

 rejlexus it immediately simulates death, and so remains 

 long enough to tire out your patience, whereas Argas 

 Fischcrii waits a few seconds, and then hurries off, 

 with a gliding motion, at a tolerably rapid pace. 

 Mr. Fullagar's drawing, which was taken from a 

 living, medium-sized specimen, gives a very good 

 idea of the creature, but would be much improved by 

 the addition of a little colour. I think it not unlikely 

 that this cre^iture will be found tolerably common if 

 well looked for in likely situations, for I have heard 

 of two cases where creatures, supposed to be bugs, 

 have been noticed when old church roofs have been 

 taken down. Their life history has not by any means 

 been satisfactorily made oiit. I have not seen a male, 

 nor have I heard of the male of Argas rcj^cx/ts yet 

 having been seen. The structure of the mouth, 

 resembling Ixodes, seems to point out their parasitic 

 nature ; but I have not yet heard of their being found 

 on their host, at least in this country, although 

 Argas rcflexiis is said to be parasitic on the pigeon, 

 and Argas Fischcrii may be parasitic on the bat ; but 

 if so, how is it that no one has yet found them on 

 these creatures ? I have carefully examined bats 

 from this very church, but have not succeeded in 

 finding the Argas on them. On February i6th I 

 saw an Argas changing its skin ; the process was 

 rather more than half completed when I fust observed 



it ; the skin part*! at the edges, either half being 

 turned backwards. On viewing the Argas as an 

 opaque object, I could see the tracheae, like whitish 

 threads, branching from two centres, over the posi- 

 tion of the spiracles ; the contractions and dilatations 



Fig. 85. The Blyborough Tick {Argas FiscJur'ii), from a 

 mounted adult specimen, showing eggs in interior. 



Fig. 86. Mouth Organs of ditto. 



Fig. 87. Foot of ditto. 



in the coeca M'cre at the same time being carried on 

 with tolerable activity. One specimen which I dis- 

 sected contained several ova, and in each of them the 

 embryo was easily seen in a considerably advanced 

 state of development. 



I must refer those interested to my paper published 

 in the " Journal of the Quekett Microscopical Club," 

 No. 33, February, 1877, for some further remarks on 

 this subject. 



C. F. George, M.R.C.S. 



"IlERB-rARis, or Herb Tiiielcn'e. Paris is 

 incorrectly spelt with a capital P. The name is from 

 the Latin Herba-paris, the best of a j^air, of a 

 betrothed couple, in reference to its four leaves being 

 set upon the stalk like a true-love knot." — Dr. Prior. 



