ANNOTATED LIST OF THE SPECIES 159 
Henonemus macrops EKigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, III, 401; 
Jigenmann, 1918, Mem. Carnegie Mus., VII, 346, text fig. 22. 
Peru to Manacapurti 
15705, 1, 34 mm., Yurimaguas, Allen, November, 1920. 
Hitherto known only from the types, in the Vienna Museum. 
Genus 58: PSEUDOSTEGOPHILUS Eigenmann and Eigenmann 
Pseudostegophilus Eigenmann and EKigenmann, 1889, Proc. Cal. Acad. Sci., (2), II, 54; 
Eigenmann and Eigenmann, 1890, Occ. Papers Cal. Acad. Sci., I, 341; 
Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, III, 400; 
Eigenmann, 1918, Mem. Carnegie Mus., VII, 349. 
Type: Stegophilus nemurus Giinther 
Upper Amazon and Mamoré 
Differing from Henonemus in having the opercle provided with four or five 
spines directed caudodorsally; the interopercle with spines directed caudoventrally ; 
eye 3.5-5.0 in the head; separated from Homodiaetus by the deeply forked caudal 
fin. 
121. PSEUDOSTEGOPHILUS NEMURUS (Ginther) 
Stegophilus nemurus Giinther, 1869, Proc. Zool. Soc. London, 429, Peruvian Amazon. 
Pseudostegophilus nemurus Eigenmann and Eigenmann, 1889, Proc. Cal. Acad. Sei., (2), II, 54, 
Maranon or Ucayah; 
Eigenmann and Eigenmann, 1890, Occ. Papers Cal. Acad. Sci., I, 341; 
Eigenmann, 1918, Mem. Carnegie Mus., VII, 350, pl. xliv, fig. 5. 
Upper Amazon to Rio Mamoré 
15716, 1, 538 mm., Inahuaya, Rio Ucayali, Allen, August, 1920. 
15969, 2, 57 and 67 mm., Iquitos, Morris, 1922. 
Genus 59: ACANTHOPOMA Liitken 
Acanthopoma Liitken, 1891 (1892), Vidensk. Meddel. Naturh. Foren. Kj6benhavn, 53, fig., annectens; 
Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, III, 401; 
Eigenmann, 1918, Mem. Carnegie Mus., VII, 354, pl. xxxvil. 
Type: Acanthopoma annectens Litken 
Rio Huallaga, known only from the single type specimen 
Gill membranes united across the isthmus in a free fold, as in Stegophilus. 
Unhke Stegophilus, Henonemus and Pseudostegophilus in not having the gill- 
opening so greatly reduced. 
122. ACANTHOPOMA ANNECTENS Litken 
Acanthopoma annectens Liitken, 1891 (1892), Vidensk. Meddel. Naturh. Foren. Kjébenhavn, 53, 
fig., Huallaga; 
