92 THE AMERICAN MONTHLY [Apr 
few hours. A portion of the sediment thus collected at 
the bottom of the tube is lifted by means of a pipette, 
and a drop of it placed on the center of a slide, when it is 
covered by a second slide ora coverglass. The specimen 
is now ready for examination and should be studied un- 
der a % lens, where the ova appear as small, round, opal- 
escent bodies. Individual ova may be studied under a 
higher power lens—1-5 to 1-8 (Fig. 1—1 Natural size ; 2 
head ; 8 tail; 4ova). These ova are well preserved when 
mounted in cast medium or in glycerine. 
After the administration of certain drugs, the adult 
worm appears in the feces as a silky, slightly curved 
thread whose color is not constant.. The parasite’s de- 
tection is facilitated by adding water to the feces and stir- 
ring to effect a perfect mixture which is then set on either 
a light or dark surface. A thin spread of diluted feces is 
in this way produced, and affords a favorable field upon 
which to find the parasite. Adult worms are preserved 
in 70 per cent alcohol. My specimens were first placed in 
alcohol,.and later ‘in glycerine for 24 hours, from which 
they were mounted in cast medium. Glycerine jelly is al- 
so a valuable mounting medium for animal parasites. The 
anchylostoma is known to be the cause of a large percent 
of deaths in tropical districts, and is of especial interest 
since Surgeon B. K. Ashford, U. 8. A., has shown it to be 
most common in Porto Rico, and other West Indies isles. | 
TAPE Worms.~Segments of these parasites are common- 
ly passed with the stool,and their study and general char- 
acteristics differ in no way from where the parasite is ex- 
pelled as a result of therapeutic measures. The freshly 
voided segments are first washed in water and then placed 
in 70 per cent alcohol for twenty-four hours, when they 
are transferred to xylol for twenty-four hours and then 
mounted as follows: A portion of a segment is placed on 
a slide, and teased to shreds. After a short exposure to 
the air (five minutes) a drop of Canada balsam is added 
