Reference for Chullin 123:2

לא היה בקי בהן ובשמותיהן בסימן אחד טמא בשני סימנין טהור והוא שיכיר עורב

and their nomenclature any bird that has one characteristic [of cleanness] is clean; but to one who is not familiar with these birds and their nomenclature any bird that has one characteristic [of cleanness is unclean],<span class="x" onmousemove="('comment',' For it might be of the species of the peres or 'ozniah.');">²</span>

Jastrow

Jastrow