COMMON OBJECTS WORTH EXAMINING. 283 



Coddington lens, a claim that lie would have hesitated 

 to make if he had known anything about the subject. 

 A single fibre of hair can be recognized as such, and can 

 be very readily distinguished from a fibre of wool, silk, 

 or cotton, all of which the beginner should examine, 

 since they will very often be found on the slide and 

 may be mistaken. Hair is easily accessible on the cat, 

 mouse, horse, and other animals. It should be examined 

 in water with a high power. The hair of the mouse is 

 very peculiar, as is also that of most bats. Colored 

 fibres of wool are often seen on a slide, having dropped 

 there from the observer's clothing or floated from the 

 carpet. They must not be mistaken for a remarkable 

 class of worms. 



11. HAIRS OF ANTHKENUS LAKVA. The " buffalo bee- 

 tle " (Anthrenus scrophuldrice, and its relative, A. mu- 

 seorum) are pests that are becoming much too common 

 in our houses. The larvae, however, can be utilized by 

 the microscopist as a supply for hairs of great interest. 

 The red dish -brown tufts on the various parts of the 

 body, especially of Anthrenus museorum, are composed 

 of hairs having a remarkable structure, which the begin- 

 ner is advised to examine for himself, especially since 

 words cannot adequately describe it. The hairs should 

 be studied in water or Canada balsam. 



12. LINGUAL RIBBONS or MOLLUSKS. The tongue, pal- 

 ate, lingual ribbon, or odontophore (it has received sev- 

 eral names) is the organ by which the water-snails rasp 

 off their food from submerged stones and plants. It is 



13* 



