[255 ] 



1balf=*aiHI:)our at the riDicroscopc, 



Mitb /IDc. Uxxttcn Wicst, if.X.S., jf.lR./ID.S., etc. 



Phthirius ing-uinalis (PL XVII., upper portion). — The charac- 

 ters which separate Phthirius from Pcdiculus are — the fusion of 

 the thorax and abdomen, and the possession of two kinds of limbs, 

 ambulatory and scansorial. It is a very remarkable form of life; 

 the fusion of thorax and abdomen and corresponding union of 

 nerve-centres, would denote it the highest form known among the 

 anoplura; but on the other hand, by the possession of rudiment- 

 ary abdominal limbs (a characteristic unknown in any other 

 example of this natural order), it makes an approach to the 

 lowest form of Arthropoda — the Millipedes and Centipedes. 



I know nothing in its way equal to the idea of huge, massive 

 power conveyed by an attentive study of one of the posterior 

 limbs in this creature. Time does not allow of entering fully into 

 it here, and it is the less needful, as the details are carefully given 

 in the Plate, with, for comparison, the corresponding limb from 

 the Hog-Louse, Hcemotopinus stiis. 



As many of our members belong to the medical profession, I 

 -think it scarcely needful to apologise for quoting a highly-interest- 

 ing case of its occurrence in the upper eyelash, from a work to 

 which some of them may not have ready access. For the ability 

 to do this, I am indebted to the kind courtesy of J. F. Streatfield, 

 one of the surgeons to the Royal London Ophthalmic Hospital, 

 Moorfields, and editor (in 1859) of the "Reports." The case is 

 ably reported by Mr. W. W. Harkness : — 



" The following case seems worthy of record, both on account 

 of its comparative rareness, and also because opportunity was 

 afforded of accurately determining the nature of the insect infest- 

 ing the eyelashes. For the very faithful drawings illustrating the 

 case, I am indebted to Mr. Streatfield, amongst whose out-patients 

 it occurred: — 



" R. P., aet. 50, a German Jewess, residing in Houndsditch, 

 applied at the Moorfields Hospital, on account of a chronic 

 ophthalmia of the left eye. On examination, the lashes of the 

 right upper eyelid were found to be thickly studded with a 

 number of dark-brown, bud-like bodies, of about i — 48th inch in 

 length, and which microscopical examination proved to be the 

 eggs of the Phthirius, or Pediculus pubis. One or two Phthirii 

 were also found half-hidden among the lashes, which were spread 

 and seemed to be kept apart by the numerous ova attached to 

 them. The eyebrow, and when first seen the lower lids, were free 



