THE society's NOTE-BOOKS. 123 



stellum, or rostrum, which they insert into the skin is somewhat 

 Fig. 2X. ^^ ^^^^^ shape (Fig. 23) ; the recurved hooks at 



its extremity being evidently intended to retain 

 the sucker in the skin. I have never seen this 

 myself and, indeed, it is said never to be seen 

 except in action. It is described as being 

 everted when required, somewhat, I imagine, 

 like a snail's horn. "The males have at the ex- 

 tremity of the abdomen, which is rounded, a 

 horny, conical, recurved, pointed spur, with 

 which they can inflict a wound ; this spur seems 

 to be the sheath of the genital organ. In the 

 female Pediculiis the extremity of the abdomen is 

 grooved, and during copulation she places her- 

 self on the back of the male." They multiply 

 with frightful rapidity. " A louse has been known 

 to produce fifty eggs in six days, and there were others still remain- 

 ing in the body." Cleanliness is the best remedy for them, destroy- 

 ing the clothes and washing the head frequently with common 

 yellow soap. The " nits " can be easily removed from the hair 

 with a small-toothed comb, after washing with vinegar and water, or 

 with spirits of wine. The young differ somewhat from the fully- 

 formed insects in my experience, especially in the antennae, the 

 last three joints of which I have found united into one, the 

 segments being only indistinctly indicated. I have never seen 

 this mentioned. These insects cast their skin several times 

 before arriving at their full growth. I possess a mounted speci- 

 men which was killed just as it was about to withdraw from its 

 old skin. The animal evidently shrinks, and in my specimen all 

 the parts appear in duplicate, so that it looks like a small Pedicu- 

 lus inside a larger one. 



D. Moore. 



Pediculus vestimenti (Plate 28, Fig. 5).— This, I think, is 

 identical with the Pig-louse, and readily distinguished from the 

 Head-louse, the P. vestimenti having a neck, which the other has 

 not, and the head is rounder. 



A. Nicholson. 



The drawing illustrating P. vestimenti is copied from Denny's 

 '' Monographia Anoplurorum." 



Editor. 



