8 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 120 
94 mm); 14993, Manacapurd, 2 (59 and 60 mm); 14984, Pérto do 
Moz, 2 (47 and 51 mm); 14988, Tonantins, 3 (59 to 94 mm); 14997, 
Tabatinga, 2 (92 and 99 mm); 14985, Porto do Moz, 20 (37 to 48 mm); 
14994, Santarém, 10 (46 to 54 mm); 14998, Obidos, 4 (47 to 71 mm); 
14991, Jutahy, 5 (43 to 73 mm); 14992, Jutahy, 3 (39 to 41 mm); 
14987, Pérto do Moz, 5 (40 to 44 mm); 14977 to 14980, Tefé, 10 (51 
to 101 mm) ; 14977 to 14980, 14982 and 14983, Tefé, 6 (74 to 100 mm); 
14996, Santarém, 3 (385 to 46 mm); 14990, Villa Bella, 6 (36 to 41 
mm); 14999, Parad, 1 (54 mm); 14995, Santarém, 1 (44 mm); 14976, 
Monte Alegre, 6 (33 to 89 mm); 14981, Tefé, 10 (63 to98 mm). The 
following have CNHM numbers: 15254, Santarém, 1 (88 mm); 54371, 
Manaus, 4 (81 to 90 mm); 54233, Manaus, 1 (49 mm); 53847, Esse- 
quibo River, 2 (41 and 43 mm); 54370, Santarém, 3 (40 to 56 mm); 
53848, Essequibo River, 4 (44 to 47 mm); 15562, Peru, 1 (53 mm). 
The following have SU numbers: 36799, Pévas, 1 (62 mm); 36660, 
near Pévas, 1 (28 mm); 2205, Lower Amazon, 1 (59 mm); 36661, 
near Pévas, 2 (23 and 26 mm); 36797, near Pévas, 1 (37 mm); 54245, 
Santarém, 3 (45 to 57 mm); 60504, Pévas, 1 (75 mm); 36798, near 
Pévas, 3 (22 to 36 mm); 36659, near Pévas, 2 (37 and 46 mm); 36796, 
near Pevas, 3 (47 to 74 mm). 
P. scalare (Lichtenstein) is the common angelfish of aquarists. 
Since 1928, when Ahl described P. eimeker from the mouth of the 
Rio Negro in the Amazon basin considerable confusion has occurred 
as to the validity of that species. P. ewmekei was thought to average 
fewer dorsal and anal rays and fewer oblique rows of scales (Schultz, 
1953) and as indicated by Ahl (1928) and Ladiges (1949, Deutsche 
Aquar. Terr., year 2, no. 3, pp. 50-52); however, most of their 
counts were based on aquarium specimens, undoubtedly inbred strains 
in aquaria, which most probably did not represent the species com- 
plex of natural populations found in the Amazon basin. The counts 
recorded in tables 3 and 4 are based on specimens from definite 
natural localities and not on aquarium-reared material. 
The counts for the syntype of P. eimeker with XIII, 24 dorsal, 
VI, 26 anal, 10 pectoral fin rays, and 36 scale rows on the side fall 
nearly in the middle of the frequency distributions for Amazon speci- 
mens of P. scalare (tables 3 and 4). Thus, I conclude that P. eimeker 
is a synonym of P. scalare. 
The differences between the color patterns of P. scalare and P. 
dumerilii, discussed under the latter species and shown in plates 1 
and 3, should make identification easy; however, P. scalare and 
P. alitum cannot be distinguished on the basis of coloration. The 
chief differences are the greater number of soft dorsal and soft anal 
fin rays and the number of scales in P. altum (tables 3 and 4). P. 
altum has 27 to 31 soft dorsal rays whereas P. scalare rarely has 
more than 26. 
