Pachycrepis, [550]
Pachytylus cinerascens, [293], [297], [298], [299], [308];
P. marmoratus, [298];
P. migratorioides, [298];
P. migratorius, [298], [299], [308];
P. nigrofasciatus, [285], [298]
Packard, on cave-Myriapods, [34];
on air sacs of locusts, [283], [294];
on classification, [173];
on development of Diplax, [419];