[595] Krabbe 1882.

[596] Baur 1901.

[597] Fünfstück 1902.

[598] Darbishire 1897.

[599] [See also p. 147.]

[600] Wolff 1905.

[601] See Chap. VII.

[602] Krabbe 1883 and 1891.

[603] Baur 1904.

[604] Sättler 1914.