1040 The American Naturalist. [December, 
with which I am best acquainted, i. e., with the parasites of man and 
the domestic animals, I rarely trust myself to diagnose a tape-worm 
without first examining the anatomy of the segment, for I have found 
that after examining no less than 1200 tape-worms of cattle and sheep, it . 
is the easiest thing in the world to make mistakes such as diagnosing 
a Moniezia planissima as M. expansa or as some other species. The 
helminthologists, all over the world have now recognized the un- 
certainty of external form, in determining Cestodes and Trematodes, 
and are revising the orders with reference to their anatomy ; and with 
this movement in full force, I cannot understand how such an exact 
observer as Linton now allows himself to publish new species based on 
the external appearance of one or two specimens. It must, of course, 
be admitted that he could probably recognize the species again, since 
he has studied the type, but he should remember that his colleagues 
cannot obtain the same impressions from any description, no matter 
how good it may be, which he obtains from seeing and studying the 
original animals. 
It is to be hoped that our friend, Dr. Linton, will obtain more ma- 
terial of the species he has described, and that he will favor us with 
exact accounts of their internal topographical anatomy. 
—C. W. STILES. 
Systematic Arrangement of the Families of Birds.’ —Prof. 
Max Fürbringer calls attention to Dr. L. Stejneger’s systematic arrange- 
ment of the families of birds as adopted in the Standard Natural His- 
tory. Although Fürbringer differs in his ideas from Stejneger, he ex- 
presses his “ volle Bewunderung ” at the latter’s system, and continues, 
“ Es ist die ernste That eines hervorragenden, in seiner Methodik auf 
den rechten Bahnen wandelnden Forschers and Denkers und verdient 
als solche den besten neueren Vogelsystemen gleich gestellt zu werden. 
Shufeldt on the Anatomy of the Humming-Birds and 
wifts.—In his review of my popular monograph of the humming- 
birds, in the October NatrurRALIsT, Dr. Shufeldt declares my description 
of the humming-bird’s tongue to be erroneous, and “ kindly invites 
my attention “ to the very careful dissections made by the Scotch anato- 
mist, W. MacGillivray,” and also his own “extensive dissections, the 
results of which were published in Forest and Stream for July 14, 1887, 
p. 581. The inference clearly is that Dr. Shufeldt would have me ap- 
pear ignorant of both these treatises, though he should know that I am 
3 Journal für Ornithologie, April, 1892. 
