SUGAR MITES. 279 



CASE Glyciphagus hippopodos [Hering, Nov. Act. 1838).— 19. Magnified sketch 

 ^ • of ditto, copied from Hering's figure. 



Hering, who described this species, and who, so far as we know, 

 is the only author who has met with it, placed it among the 

 Sarcoptid^, but although the habitat where it was found makes 

 it not unnatural that he should have done so, there can be no 

 doubt that its characters are all those of a Glyciphagus. It was 

 obtained by Hering from a horse, whose hind feet had for several 

 months had itch mites to such a degree, that 

 although young and in other respects sound, it 

 was so useless that it had to be killed. Both 

 the hind hoofs were quite disorganised, the 

 frog and the sole consisting of a soft fibrous 

 mass, in the wrinkles of which a stinking liquid 

 was secreted. The cracks in the hoof arose 

 from the destruction of the edges of the hoof 

 which became separated and soft, and the animal 

 became unable to go on hard ground. In the 

 end the sore spread at the back from the ball to the flexors 

 and muscle of the fetlock. In the lifetime of the animal very 

 few mites were perceived, but when it was dead, the hoof, in 

 order that its abnormal form might be modelled, was covered 

 with plaster both outside and inside to the frog, and then they were 

 found to be in numbers. They had, as is usual after the death 

 of the harbouring animal, left their retreats and congregated to 

 the edge of the sore and the hardened hide. Although at this 

 time the temperature was several times l^elow the freezing point 

 (in the night it fell to 10 R.) ; still after several weeks living 

 mites were found. It appears that the cold hindered a further 

 decomposition in the soft parts, and therefore the mites continued 

 to live on in their wonted element. 



Glyciphagus buski (see Cooper and Busk's Microscopic Journal, 1842}. 

 It is probably here that an unnamed species made known by 



