186 REPORT OF THE COMMISSIONER OF FISH AND FISHERIES. 
16. Genus et sp. incert. 
Psorosperms of Gobius fluviatilis, Leydig, 1851, Miiller’s Archiv., p. 223, name 
only; ib. of Gobio [error] fluviatilis Ludwig, 1888, Jabresber. d. rhein. 
Fisch-Vereins, 1888, p. 30. 
Habitat.—Body cavity of Gobius fluviatilis L.' (goby). 
17. Genus et sp, incert. 
Psorosperm of crocodile, Solger, 1877, Jahresber. schles. Gesellsch. f. Vaterl. 
Cultur, Liv, p. 45. 
Name only, with statement that it will be fully described elsewhere. 
Habitat.—m mucosa and muscularis of intestinal canal of “ croco- 
dile.” 
18. Genus et sp, incert. 
Psorosperm of Chondrostoma nasus, Leydig, Miiller’s Archiv., 1851, p. 222. 
No description or figure. 
Habitat.—Cysts in roots of tongue of Chondrostoma nasus L. 
19. Genus et sp. incert. 
Psorosperms of Leuciscus rutilus, Leydig, Miiller’s Archiv., 1851, pp. 222-3. 
No description or figure. 
Habitat.—White clumps of ‘‘psorosperms” in the heart (auriculo- 
ventricular valve) of Leuciscus rutilus; also in heart blood of samé fish. 
20. Genus et sp. incert. 
Psorosperms of Cyprinus tinea, Lieberkiihn, 1854, Bull. Acad. Roy. Belg., xx1, 
pt. 2, p. 22. 
No description. 
Habitat.—Scales of Tinca tinea L. (tench). 
21. Genus et sp. incert. 
Psorosperms of Cyprinus erythrophthalmus, Lieberkiihn, 1854, Bull. Acad. Roy. 
Belg., Xx, pt. 2, p. 22. 
Mention of occurrence only; no description. 
Habitat.—Subsquamous, on Leuciscus (Scardinius) erythrophthalmus. 
22. Genus et sp. incert. 
Psorosperms of Gasterosteus aculeatus, Hensen,? in Wittmack, 1875, Beitriige 
z. Fischerei-Statistik d. deutsch. Reichs, p. 190. 
Mention only; no description. 
Habitat.-—On Gasterosteus aculeatus L. (stickleback) near Kiel. 
23. Genus et sp. incert. 
Psorosperms of Lucioperca sandra, Heckel & Kner, 1858, Die Siisswasserfische 
der éstreichische Monarchie, Leipzig, p. 12; ib. Wittmack, 1875, Beitrige 
z. Fischerei-Statistik d. deutsch. Reichs, p. 190. 
Heckel and Kner say: 
Their gills are often beset with small cysts.filled with a gelatinous fluid (the so- 
called psorosperms) and in this condition they are regarded as unfit for food. 
1'The great similarity of name between the present fish and Gobio fluviatilis, and 
the presence of a species upon the latter in the same situation (body cavity, see p. 
243) suggests the possibility of an orthographic error. 
2 In response to an inquiry, Dr. Wittmack kindly informed me that Prof. Hensen’s 
observation is unpublished, having been made upon a statistical question sheet. 
