276 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 9& 
TaBLE 10.—Counts made on subspecies of Thoracocharax maculatus 
Number of rays in anal fin 
Subspecies 
iii, 27 iii, 28 lii, 29 iii, 30 iii, 31 lii, 32 ili, 33 
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Genus CHARACIDIUM Reinhardt 
VOLADORITAS 
Characidium REINHARDT, Overs. Danske Vid. Selsk. Forh. Kjgbenhavn, 1866, 
p. 56, pl. 2, fig. 1-2. (Type, Characidium fasciatum Reinhardt.) 
Chorimycterus Corr, Amer. Nat., vol. 28, p. 67, 1894. (Type, Chorimycterus 
tenuis Cope.) 
Nanognathus BoULENGER, Bol. Mus. Zool. Anat. Comp. Univ. Torino, vol. 10, 
No. 196, p. 3, 1895. (Type, Nanognathus borelli Boulenger.) 
Poecilosomatops FowuEr, Proc. Acad. Nat. Sci. Philadelphia, vol. 58, p. 323, 1906. 
(Type, Characidium etheostoma Cope.) 
Jobertina PriuEGRin, Bull. Mus. Hist. Nat. Paris, vol. 15, pp. 149, 151, 1909. 
(Type, Characidium (Jobertina) interruptum Pellegrin.) 
Upon examination of the fishes of this general relationship from the 
Maracaibo Basin, I have observed certain features that caused me to 
ponder for some time over the generic relationships, as well as the 
validity of certain species, but I do not have available certain critical 
species that must be studied before the fishes of this genus are properly 
compared. In the National Museum are two of Liitken’s specimens 
from South America (U.S. N. M. No. 44950) of what I believe is the 
valid Characidium fasciatum Liitken. In coloration and in all re- 
spects they agree with his figures. I partially dried the lower jaw of 
one of these specimens and found a second row of minute teeth pro- 
jecting inward along the bases of the single row of larger teeth. 
Chorimycterus Cope is described as having two series of teeth in the 
lower jaw, but Fowler (1906, p. 325) says, ‘‘The presence of biser- 
ial mandibular teeth is entirely fallacious, as both of the cotypes 
before me have but a single series in the mandible.” JI could believe 
the latter statement if I knew how carefully the cotypes were ex- 
amined, but I am practically certain that Cope’s observations are 
correct, since these teeth are difficult to observe, especially when only 
a low-power hand lens is used. When the lower jaw is dried a little, 
the teeth are obvious. 
_ In substantiation of Cope’s observation, I have found that alli 
three species of Characidium collected by me have the two series of 
mandibular teeth and that they are somewhat prominent in the speci- 
mens from the Rio Chama and the Rio Torbes. No doubt all or 
at least many of the species now referred to the genus Characidium 
