eZ ALICE M. BORING AND RAYMOND PEARL 
are cultivated by inbreeding.”” In 1909, he started this particu- 
lar stock with one cock and six hens. From then on, he has 
inbred them. In the F, generation in 1911 there appeared two 
hermaphrodites out of 80 birds, and in F; in 1912, there were 
three more hermaphrodites out of 80 birds. These are the five 
birds sent to Maine. These were by no means all the birds of 
the sort which Herr Houwink had produced. When one of the 
writers (R. P.) visited his breeding plant in Meppel in 1910 there 
were then on hand a considerable number of these supposed 
hermaphrodite birds. Herr Houwink was of the opinion, as 
already stated, that inbreeding was the cause of these abnor- 
malities, but without producing evidence which was conclusive 
to this effect. 
These Holland birds were numbered 1425, 1426, 1427, 1428 and 
1429 on the Experiment Station poultry plant, and will go by 
these numbers in this paper. One of the other three hermaphro- 
dites was a small black bird sent to the Experiment Station by 
Prof. Horace Atwood of West Virginia. This will be referred to 
as Atwood’s black hermaphrodite. The seventh hermaphrodite 
appeared in the Station flock of pure Barred Plymouth Rock 
ancestry. The number of this bird is 1349. The eighth bird, 
1616, was sent from Michigan by Professor Dexter. These eight 
birds vary in the proportion of male and female in their make-up, 
both as to external and internal structure, and behavior. It 
seems clearest to arrange them in a series from the most female 
at one end to the most male at the other end as the various 
features of structure and behavior are taken up, using the 
structure of the prmary sex organs as the basis for this serial 
arrangement. 
This study has been carried a little further and included other 
birds with abnormal sex behavior, but normal structure. That 
is, to complete the more female end of the series, we have studied 
several apparently normal hens that tread other hens. Of these, 
1422 was sent from West Virginia by Professor Atwood as a pos- 
sible hermaphrodite but has behaved normally in Maine. K134 
and M408 were two such birds reared at the Station plant and 
finally killed to study their anatomy and histology. 
