P. 31, line 6 from bottom: delete “human,” as Leidy really worked with Endamoeba blattÆ, parasitic in the gut of the cockroach.

P. 43, line 12 from bottom: for “John’s” read “Johns.”

P. 44, line 13 from bottom: for “Amoeba buccalis, Sternberg,” read “Amoeba buccalis, Steinberg.”

P. 46, line 13 from top: for “breath” read “breadth.”

P. 53, In footnote ¹, line 6 from bottom: insert “see” before Arch. f. Protistenk.

P. 75: To paragraph regarding development of the parasite in the fly’s salivary glands, add that the crithidial phase takes two to five days.

P. 111, line 8 from top: the date of Sangiorgi should be 1911.

P. 142, line 7 from top: insert “Genus.” before Eimeria.

P. 252, Insert heading “Family. OpisthorchiidÆ, Braun, 1901,” above “Sub-family. OpisthorchiinÆ, Looss, 1899.”

P. 351, description of fig.255, line 3: for “Thoma” read “Thomas.”

P. 471, line 15 from bottom: for “alcohol 100 parts” read “alcohol 100c.c.”

P. 472, line 11 from bottom: for “Or (2) 10 per cent. formalin,” read “Or (2) fix in hot 10 per cent. formalin.”

P. 493, line 21 from top: for “Conoy” read “Couvy.”

P. 589, line 2 from top: for “carnosa” read “carnaria.”

P. 620, line 15 from top: for “fo” read “of.”

P. 622, line 12 from bottom: delete comma after quantity.

P. 626, line 6 from bottom: delete comma after Mackie (1915).

P. 638: insert title “TREMATODES” above that of “Fascioliasis.”

P. 709, line 9 from bottom: omit second Pediculus capitis.

P. 748, line 8 from top: for “cytologica” read “cytological.”

P. 753, line 4 from bottom: for “Fercocercous” read “Furcocercous.”

P. 755 line 7: for “Oncocerca” read “Onchocerca.”