G AM A SID S. 171 



CASE confounded there with the Argas reflexus, which is more specially 

 XI. . , . 



assigned to pigeons. 



It may be most easily observed in the cages and aviaries 

 of singing birds, and they may harbour there, even although the 

 most scrupulous cleanliness is exercised, especially if the perches 

 used for the birds are made of hollow canes, and not solid wood. 

 It is in these hollow canes that they most particularly harbour, and 

 we may generally find them there at all seasons of the year. But 

 it is very probable that, although it is in these recesses that we 

 find them when we seek them during the daytime, they sally out 

 during the night, and settle on the sleeping birds, in order to 

 suck their blood. That they do so, is shown by their digestive 

 organs being generally full of it in all individuals, both young 

 and adult. It is this blood which gives to these animalcules 

 their colour, which is dark purplish or brown, when they are 

 filled ; when empty, they are colourless. In the same retreats, 

 are found a multitude of excessively fine exuviae, or white cast 

 skins, attesting sufficiently numerous moultings. In this heap 

 are seen also colourless eggs, ellipsoid, nearly equalling in length 

 the fifth part of the adult animal, which is scarcely a third of a 

 line at the most. 



These eggs are said to become larger in maturing, and to take 

 gradually, like those of the spiders, the form of the young one 

 which is coming out. The young have only six feet ) the body is 

 much longer and more inflated than that of the individuals of the 

 same size which have already their eight legs ; these last are 

 slenderer, and more agile, and the posterior pair are much longer 

 than the body, and continue pellucid and colourless as at first ; 

 but it is not long before they go and fill their stomachs, and the 

 blood that they swallow makes them bright red at first, then dull, 

 then brownish, in proportion as it becomes more altered and 

 digested. 



Bory de St. Vincent (Ann. Sc. Nat. ist Ser. xxxv.) relates that 

 a woman of forty years old, who felt the most intolerable itching 



