CASE OF ANDREW MITCHELL. 203 



hairs or laminae a rapid motion, and creates a current, by which its prey 

 is brought within the concavity they form. The mandibles above men- 

 tioned are stout, and furnished with a small hook at the end, which 

 catches at each movement the projection upon the palpi above noticed 

 The moment an animalcula touches the internal surface of the vibrissae, 

 they close upon it, and it is forthwith conveyed to the mouth and de- 

 voured. When at rest, the fan-like portions of the palpi are folded, and 

 brought into contact or alongside the basal joint, in which position they 

 cover the upper part of the mouth. The body of the creature is pellucid 

 and diaphanous ; and the internal parts are plainly visible through the 

 integuments. One of the most striking peculiarities of this animal is the 

 mode in which the motion is communicated to the fan-like process of 

 the palpi, in order to create a current ; for in this instance, it is not ef- 

 fected by the movement of the hairs themselves, nor by the rapid mo- 

 tion of ciliae attached to them, as is seen in various Crustacea and other 

 insects, but by the mechanical intervention of another oral instrument. 

 The animal was kept for some time in a glass of water, but died before 

 undergoing a metamorphosis. 



Case of Andrew Mitchell, aged ten years, son of Robert Mitchell of 

 North Charlton, in the parish ofEllingham, Northumberland, Shep- 

 herd, and Ann his Wife. 



From about the 1st of March 1839, the patient complained of pains 

 in his head, particularly on each side above the ears, and of what he 

 termed " gumbles," which shifted to different parts of his head ; and ex- 

 pressed his belief of something moving about in his head. These pains 

 and feels continued and increased till between nine and ten of the night 

 of the 14th June following, when, r whilst patient was in bed, an insect, 

 as hereafter described, was discharged from his left nostril. Some blood 

 followed on the day after the discharge of the insect. 



The pains and feels continued with some interruptions till between 

 five and six p. M. of July 5. following, when, whilst patient was sitting 

 in the cottage, a second insect, exactly similar to that above mentioned, 

 was discharged from the same nostril. For the first fortnight after this 

 second insect was discharged, the pains of the head, particularly on the 

 sides of the face above the ears, were very severe and distracting. 



A third discharge of a similar but somewhat smaller insect took place 

 on Saturday the 10th of August, whilst the patient was playing with 

 other children in an out-house, being exactly five weeks and a day from 

 the discharge of the second. A slight discharge of a tough mucus, some- 

 times tinged with blood, takes place occasionally from the opposite nos- 



