MEMOIRS

OF THE

OAENEGIE MUSEUM

Vol. VII. ,, ^

No. 5.

THE PYGIDIID^, A FAMILY OF SOUTH AMERICAN CATFISHES.'

By Carl H. Eigenmann.

(Plates XXXVI-LVI.)

Introduction.

The Pygidiidm are a family of South American catfishes distinguished exter-
nally by the absence of an adipose fin and by the posterior position of the dorsal.
Most of them are even more readily distinguished by the i)resence of spines or
thorns on the opercle and interopercle, by twin barbels at the angle of the mouth,
and by the absence of all mental barbels. Other characters of the catfishes may be
present or absent, and by addition, subtraction, or modification of characters,
various subfamilies have been formed. A description of the characteristic struc-
tures is given on pages 276-279. The basal habit of all the members of the family
is that of burrowing. The oi)ercular and interopercular spines are an adaptation
to their habit of insinuation, which is at the root of the commensalism, parasitism,
and worse, to which some highly specialized members of the family are addicted.

Nematogcnys from central ( 'hil(>, the only representative of the XematoycnyiiKe,
is probably more nearly like the ancestors of the Pyyidiidw than the other living
representatives of the family. It recalls the SUurida: by having a pungent i)ect()ral
spine, serrated on its posterior margin, by ha\ing but one barl)el at the angle of the
mouth (the remaining subfamilies having two), by having a pair of mental barbels,

' Contribution from the Zoological Laboratory of Indiana University, No. 164.

259

260 MEMOIRS OF THE CARNEGIE MUSEUM.

and In^ the absence of opercular aiul interopercular spines, wliich are present in the
other subfamihes. Its dorsal is farther forward than in the other members of the
family, again in this resi^cct approaching the Siluridce. It resembles the rest of the
Pygidiidoc in lacking an adipose fin and in the case of some specimens by having
a nasal barbel. I am not able to speak with certainty of its air-bladder.^

The princii)al subfamily is that of the Pygidiince. In addition to the main
characteristics of the family, the members of the subfamily have a barbel on the
anterior nostril, the gill-membranes are free from the isthmus, the teeth are in
bands. The genera of the Pijgidiincc differ but little from each other. Eremo-
philus, found on the plains of Bogota, has lost its ventrals; Hatcheria, hving in the
Andes of Argentina and C'hile, has an elongate dorsal fin, Scleronema from the
Uruguay has modified maxillaries and maxillary barbels. The main genus, Pygi-
dium, with sixty-three species, is found everywhere in the mountains and sparingly
in the lowlands. It attains the highest altitudes and flourishes in Lake Titicaca,
where it is a food-fish of importance. The only food-fish at Bogota is the closely
related Eremophilus, "El Capitan." Seventy-one of the known species of the
family belong to the subfamily Pygidiince.

■ The genus P<ir!(iliiis may lie related to NcmaUH/ciiys, but it is more likely to be related to Phreato-
bius, Ihptapkrut!, MijujiUouti, Iji plurhaindin (for Lcplaglanis which is prc-occupied), etc. The only speci-
meu recorded has beeu lost.^'^/AlVtfoaJiciniS

^' 1. I'AKIOLIUS* Cope.

I'aridlius, C^oPE, Proc. Acad. Nat. Sci. Phila., 1871, p. 289.

Type. — Pariolius armillalus Cope.

Similar to Pygidium; no nasal barbel; a single barbel at the angle of the mouth; two pairs of mental
barbels; no armature on the opercles; gill-oiieuings wide; teeth brush-like; origin of the dorsal behind that
of the ventrals; anus under dorsal; anal short.

Little can be said about the rclationsliii) of this genus until its skull and air-bladder are examined.
It appears to be closely rehitetl to some members of the Piindoduuc. There are no specimens available for
examination. It is known only from the tj'i)e of the species, and that has been lost.

Habitat. — Basin of Peruvian Amazons.
Pariolius armillatus Cope, I. c. (Ambyiacu); Eigenm.\nn & Eigenmann, Proc. Cal. Acad. Sci. (2), II,
1SS9, p. 50; Occasional Papers Cal. Acad. Sci., I, 1890, p. 324; Proc. U. S. Nat. Mus., XIV, 1891,
p. 36; Eigenmann, Reports Princeton Univ. Exped. Patagonia, III, 1910, p. 398.

"Head fiat rounded, eyes small, superior, covered by the skin. Head 4.5 times in length to basis
of caudal fin. De])th at D. I. one-half length to basis pectoral fin; width of head two-thirds the same dis-
tance. Interorbital width 3. GO times in length of head. Maxillary and external mental barbels extending
beyond basis of pectoral; inner mental barbel one-half the same. Radii D. 7; P. S; V. 6; A. 11; caudal
acuminate. Skin entirely smooth."

* I am not sure of the origin of this generic name. Is it from the proper name Parioli, or from
TrapaioXifui = lo trick, hcncc a trickster or simulator, or from Trapd = with, and didXos = speckled'?

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 261

Nearest the Pyyidmice arc the Pareiodontince, which lack a nasal barbel. The
teeth are very peculiar and in a single series (See Fig. 21) and the gill-membranes
are attached. But one species is known. The Nematugemjinw, Pygidiince, and
Pareiodontince are free-living, and have a terminal or subterminal mouth and pointed
or incisor teeth.

The Stegophilinoe, Vandelliince, and Tridenlince differ widely from the members
of the above-mentioned subfamilies in structure and habit. They are all small or
minute; the mouth is inferior; the head flat below; the lower barbel at the angle of
the mouth is minute. The jaws are weak, the teeth absent or slender. The gill-
opening, in all but Acanthopoma, is greatly restricted, which, put in terms of habit,
means that the mouth is suctorial. Some of them are parasites, or commensals.

The Tridenlince differ in having the anal fin much longer than the others.
Nothing is known of their habits and they are so small (the largest known specimen
is but 27 mm. long) that it is a wonder that any of them have arrived in the bottles
of the naturalist.

In the Vandelliince the teeth are reduced to a minimum, and the rami of the
lower jaw do not meet in the middle. The differences between the genera are
minute, but well marked. The habits of these fishes, as well as those of the next
subfarnily, are discussed below.

The Stegophilinoe have a very large number of minute teeth in definite series
in both jaws. The rami of the lower jaw meet in the middle. The genus Acantho-
poma stands out in that its gill-membranes, while united, are free from the isthmus.
The genus, Henonemus, is well marked by the small number of opercular spines.
Ochmacanthus has numerous accessory caudal rays above and below, which make
the tail look hke that of a tadpole. The remaining genera, Stcgophilus, Homo-
dioetus, and Pseudostegophilus, might well be united. They differ from each other
largely in the position of the ventrals, the shape of the caudal, and in the number of
accessory rays.

Habits.

The habits, as well as the distribution, of various members of the Pygidiidce
have been derived from the general tendency of the catfishes to get under banks,
under logs, out of the way, and out of sight. This general tendency has been
modified into the specialized, insinuating habit of the Pygidiidw, for which the
opercular spines and the eel-like body arc adai)tations.

On the plains of Bogota the Indians secured the largest specimens of Eremo-
philus by thrusting their arms to the bottom of holes in the banks of streams.
At Honda I found one species buried in the sand in the bottom of the stream. It

262 MEMOIRS OF THE CARNEGIE MUSEUM.

would dart from its hiding place as I raked my fingers through the sand, to dart
into the sand again much like a lancelet or young lamprey, or to dodge under a
rock. Mr. E. B. WilUamson wrote me that he noticed another species clinging to
the vertical sides of a waterfall. It looked like a water- weed, but he found by
watching closely that every little while the sujiposed weed would move up the wall
a short distance, and by using his butterfly-net he secured specimens. It is this
habit assisted by the opercular spines that accounts for the fact that the species of
the genus Pijgidium are found in every mountain-stream.

The habit of insinuating themselves into crevices is undoubtedly also the
starting point of the habit of resorting to the gill-cavities and probably other organs
of larger fishes. There is a widely distributed belief among the Indians of the
Amazon Valley, that fishes called "C'andiru" enter the urethrse of bathers. Some
travelers who have had this habit reported to them have simply dismissed the matter
as absurd. Others have made attempts to identify the fish with results that have
not always been fortunate. The native name, Candiru, is applied to some fishes
{Cetopsis of the Cetopsidce) at least a foot long, and at least two inches thick, as well
as to minute slender fishes, species of Vandellia, which might enter the urethra
without violating the law that the greater cannot enter the less. The habit has
been attributed to the large Cetopsis, to Pareiodon, more moderate in size and yet
too large, and to some species of Vandellia and to Acanthopoma. It is, of course,
possible that the young of the larger Candiriis have the urinophilous habit. It is
also possible that the Indians consider the small Candiriis (species of Vandellia)
as the j'oung of the larger Candiriis, members of the genus Cetopsis, which according
to the classification adopted, belong to a different family. The habit is also phys-
ically possible for the species of Tridens, of Miuroglanis, of Paravandellia, Stego-
philus, Branchioica, and for some of the minute species or young of Pygidium.
However, these have not been indicated as being Candiriis. As far as I am able
to find, the first notice of the peculiar habit is given by Spix {Selecta Genera et Species
Piscium, 1829, p. viii) , who says of Cetopsis:

De alio pisce horainibus infesto nonnulla afferre debeo, quem Brasilienses Candiru, Hispani
ill proviiK'ia Maynas dcgentcs Canero mincupant. Singulari enim instinctu incitatur in ostia
cxLTctoria corporis humani intrandi, quae quum igitur in iis, qui in flumine lavant, attingit,
summa cum violentia irrepit, iheque carnem morsu appetens, dolores, imo vitse periculum affert,
Urinffi odore hi pisciculi valde alliciuntur, cjuain ob causani accolie intraturi flumen amazonum,
cujus sinus hac peste abundant, prseputium ligula constringunt, et a niingendo abstinent. Pertinet
hie i)iscis ad Cetopscos, quod tiepinximus, genus; at nescio, an descriptarum specieruiii (C.
candiru et C. ccecutiens) individua juniora, an tertise cujusdain speciei minoris individua crudeli
hoc instinctu a natura sint donata.

EIGENMANN: the PYGIDIID.E, a family of south AMERICAN CATFISHES. 263

I am indebted to Professor Selatie E. Stout for the following translation :

I should briefly mention another fish which is dangerous to man. The Brazihans call it
Candtru; the Spaniards in Maynas' call it Canero. It is impelled by a curious instinct to enter
the excretory openings of the human body. Whenever it comes in contact with these openings
of persons bathing in the stream, it violently forces its way in, and having entered, it causes
constant pain, and even danger of life, by biting the flesh. These fishes are greatly attracted by
the odor of urine. For this reason, those who dwell along the Amazon, when about to enter the
stream, whose bays abound with this pest, tic a cord tightly around the prepuce and refrain from
urinating. This fish belongs to Cetopsis, a genus which I have already described. Biit I do not
know whether it is the younger individuals of the two species which I have described (C candiru
and C. coecutiens), or whether a third species of smaller fishes has been given this cruel instinct
by nature.

The habit here described by Spix in reality belongs to fishes of which he did
not secure specimens.

In 1808, Domingo Vandelli, professor of natural history at Lisbon, sent Lace-
pede three small fishes, which he placed with the Loricariidce. They were described
by Valenciennes (Cuvier & Valenciennes, Hist. Nat. Poiss., XVIII, 1846, p. 386,
pi. 547) as Vandellia cirrhosa, and placed in their Esoces. Nothing was said of the
habits, and even the habitat of the specimens was unknown. The identification
of Vandellia with the urinophilous habit came later.

Castelnau in his Animaux d'Amerique du Sud, Poissons, 1855, saj'S of his
Trichomycterus pusillus = Pareiodon microps Kner:

Cette espece est, de la part des p^cheurs de I'Araguay, I'objet d'un pr^jug6 des plus singulicrs,
ils pr^tendent qu'il est trfe dangcreux d'uriner en riviere: car, disent ils, ce petit animal s'^lance
hors de I'eau et penetre dans I'urethre en remontant Ic long de la, colonne liquide.

As this species reaches a length of at least six inches and a corresponding thick-
ness, Castelnau was probably mistaken in the species acting in this remarkable
manner.

It seems that Paul Marcoy {Voyage a travers VAmerique du Sud, Vol. IT, p.
145-147) gives an account with a figure of a Candiru. I have not seen this book,
but Liitken says: "Etude de Candiru signerct med den Rejsendes Initialer, er en
fuldstandig Umulighed, hvad den saa skal forstille"(V'irfeHsA'. Meddel. Naturh.
Foren. Kjobenhaim, 1891, j). 60).

Lange "In the Amazon Jungle," p. 214, says:

In fact, throughout the Amazon this little worm-like creature, called the kandiroo, is so
omnipresent that a bath-house of a particular construction is necessary. The kandiroo is usually

' Probably Maind, an Igarap6 tributary to the Amazon, near the Rio Negro; or a province of Peru
with Moyobamba for its capital.

264 MEMOIRS OF THE CARNEGIE MUSEUM.

three to four inches long and one-sixteenth in thickness. It belongs to the himprcys, and its
particular group is the Myxinos or slime-fish. Its body is coated with a peculiar mucus. It is
dangerous to human beings, because when they are takinji a bath in the river it will approach
and with a swift, powerful movement penetrate one of the natural (ipeniiigs of the bod.y, whence
it can be removed only by a difficult and dangerous operation.

A small but hard and pointed dorsal fin acts as a barb and prevents the fish from being drawn
back. While I was in Reniatc de Males the local doctor was called upon to remove a kandiroo
from the urethra of a man. The man subsequently died from tiie hemorrhage following the
operation.

The Candiru does not belong to the lamiircys and its particular group is not
M^'xinos. The lamjireys are not found in the Amazon Valley. Its dorsal fin is
neither hard nor pointed, and hence cannot act as a barb to prevent the fish from
being withdrawn. The retrorse spines on the interopercle and opercle are the
obstacles which would prevent it from being withdrawn.

The question naturally arises: Is Lange more trustworthy in his account of
the habit than in his account of the structure and relationshi}) of the Candiri'i?

The only known specimen of Acanthopoma annectens, another Candiru, seems
to have been collected by Gustav Wallis. In an article, " Mittheilung von C. Miiller
iiber die Reise von Gustav Wallis" in Die Natur, Zeitung von P. Ule u. K. Miiller,
XIX, No. 23, p. 180, mention is made of the habits of presumably this species,
though it may have been drawn from the general report given the traveler concern-
ing the Candiri'i. Liitken quotes:

In diesen noch so wenig bekannten Owiissern, namentlich im Huallaga, beobachtete der
Rei.sende (G. AV.) einen Fisch, d(>n ich der Aufmerksamkeit der Wissenschaft ganz besonders
empfehlen will. ;Man neiint ilni dort den Candiru und fiirchtet ilm mit Recht ebensosehr fiir
lias Gebiet iles Wassers, wie man fiir das des Landcs die Moskitos und Ameisen fiirchtet. An
sich selbst ist cs nur ein kleines, kaum .75 Spannen langes Ding von welsartigem Korperbau,
mit breitem, abgerundeteni Kopfe, auf dem die beiden Augen ziemlich dicht neben einander licgen,
wiihrend die beiden Brustflossen flugelartig dicht untcr ihin sich ausbreiten und der iibrige
K<")r()ertheil keilformig zulauft. Den Riicken ziert eine dunklere Fiirbung mit undeutlich ver-
laufenden Flecken, so dass das Geschopfchen an sich selbst kaum irgendwie durch eine hervor-
ragende Eigenthtimlichkeit ausgezeichnet ist. Eine umso schrecklichere Plage ist es fiir den
Badenden, eine Art Blutegel niimlich, dor mit unglaublicher Schwimmfertigkeit jenem zu Leibe
geht, ihm iiberall schropfkopfahnliche Wunden beibringt und, wenn es ihm gelungen, sich dadurch
an dem Korper festzusetzeii, in der Wunde ein Nadellnindel ausspreizt, an dem er wie an Wider-
haken sich derart festklammert, dass er nur durch cine schinerzhafte Operation aus dem Korper
cntfernt werden kann. Diese Unart des Fisches ist umso grosser und gefiihrlicher als er am lieb-
sten die geheimsten Korpertheile aussucht; man erzahlt sich Fiille, die bei der Operation mit dem
Tode endeten. Ich werde dafiir Sorge tragen, dass dieser seltsame Fisch, den ich in Spiritus vor
mir habe, in die rechten wissenschaftlichen Hiinde gelangt und .seinen wissenschaftlichen Namen
empfjingt, den er noch nicht hat.

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 265

Boulcngor {Proc. Zool. Soc. London, 1897, p. 901) says of Vanddlia cirrhosa,
the urinophilous Candiru, par excellence:

The "Candyru," as the fish is called, is much dreaded by the natives of the Jurua district,
who, in order to protect themselves, rarely enter the river without covering their genitalia by
means of a sheath formed of a small coconut-shell, with a minute perforation to let out urine,
maintained in a sort of bag of palm-fibers suspended from a belt of the same material. The fish
is attracted by the urine, and when once it has made its way into the urethra, cannot be pulled
out again, owing to the spines which arm its opercles. The onlj^ means of preventing it from
reaching the l)ladder, where it causes inflammation and ultimately death, is to instantlj' amputate
the penis; and at Tres Unidos, Dr. Bach had actually examined a man and three boys with
amputated penis as a result of this dreadful accident. Dr. Bach was therefore satisfied that the
account given of this extraordinary habit of the "Candyru" is perfectly trustworthy. Mr.
Boulcnger further showed a photograph, taken by Dr. Bach, of two nude Indians wearing the
protective purse.

It is to be noted here that this evidence is only circumstantial. Dr. Bach did
not himself operate or help to operate to remove the Candiru and a much simpler
operation than amputation would be sufficient to remove it.

The literature on the evil repute of members of tlie Pygidiidoe has been re-
viewed by Pellegrin. In Bidletin Societe Philomathique dc Paris (10), I, 1909, pp.
101-104 [5-8 of the reprint], he says:

Le Dr. C. Jobert qui accomplit au Br^sil, en 1877, un voyage oil il rassembla des matdriaux
ichthyologiques considerables, a consacrd a la question ilu Candiru un memoire des plus docu-
mentes, ou il n'admet pas sans reserve les declarations du practicien amcricain cite par G. A.
Boulenger. ' Le Dr. Bach,' ecrit-il, ' n'a pas vu le petit Poisson in situ ; la chose est regrettable et,
cette fois encore, nous ne sortons pas du cercle de la Icgcnde.'

Toutefois, le Dr. Jobert rapporte les dires d'un m^decin tres esfime de Belem (Panl), le Dr.
Castro, qui lui afiirma avoir oxtrait do I'urcthre d'unc' lu'gresse un petit Candiru qui y avait
p^netre pendant la miction, alors qu'elle se baignait en riviere.

Mais ce qui fait le grand interet de I'article du Dr. Jobert, ce sont les renseignements qu'il
a pu lui-meme recueillir sur place au Bresil au sujet des Candirus.

Les Paraenses en distingueraieiit deux esp^ces, rune jietite, <iui s'introduirait dans I'urcthre
des baigneurs, I'autre de plus grande taille, ' trop grande pour tenter ces memes operations, mais
redoutable par les blessures qu'elle fait sur n'im]iorte qu(>lle partie du corps. On donne a cette
dernierc le nom de Candiru de Cavallo et les indigenes pretcnilent (lu'elle attaque les chevaux
pendant la baignade.' Au sujet de celle-ci il rapporte en outre les faits suivants:

'Un jour, t\ un Miilie enviion en aval de Para, je voulus me l)aigner sans souci des Candirus
qu'on m'assurait etre tres abondants en cet endroit. Je n'etais pas dans I'eau depuis cinq minutes
que je resscntis dans le region lombaire, au ventre, sur le cotes de la poitrine, comme de legers
coups de griffes qui se succedaient rapidemenl. V'oyant I'eau .se teinter de rouge autour de moi^
je me h^tai de regagner le rivage et je constatai que, dans le region on j'avais eprouve la sensation

266 MEMOIRS OF THE CARNEGIE MUSEUM.

de ces coups de griffc, le sang s'^chapiiait dc blessures en scarifications paralleles, qui eussent pu
etre attribuecs a un instrument, tant olios ^taient regulioros; olios constituaient dcs groupes de
5 a, 6 lignos, longues d'un oentimetre au plus ot tics rapprooh^^os; je n'ai pas cherche a apprecier
a profondeur, niais ces blossuros tres ^troites saignaiont abondanuiient.'

Les Poissons qui out attatiuo ainsi le Dr. Jobert a]5]iartionnent suivant nioi, incontestablement
au genre Vandellie, peut-etre menie k I'espece VandeUia Wieneri. Si Ton se rcporte a la descrip-
tion donncc plus haut do la liouchc et de I'appareil operculairo, on s'oxpliquora ainsi facilement le
fonctionncnicnt de ces divers organes; on comprondra aisoment quo la dcnii-couronne de dents en
crochet placde en avant de la bouche, dents susceptibles d'un certain degre d' erection et au nombre
de 5 0.6 principales produit ces scarifications paralleles, regidiere et en groupe de 5 a 6 lignes. Les
Opines interoporculaires du dessous do la tete, aussi un pcu eroctilos, pouvont ^galement, dans
une certaine niesurc, dechirer les t^>guments, mais elles doivent sourtout scrvir a la fixation.
Quant aux (Opines operculaires du dessus de la tete, elles me semblent plutot, ^tant donn^e la
direction de lour i)()intc, destin6es k facilitcr la progression de I'animal et a empecher tout recul
lors-qu'il s'engage dans un conduit ^-troit, par example entre les lamelles branchiales des Platy-
stomes.

Sans vouloir trancher la question de la penetration des Vandellies dans I'urethre, pour laquelle
je ne puis apporter des documents nouveaux, il me parait tout au moins demontre en rapprochant
les details anatomiques que j'ai pu constater sur les VandeUia Wieneri, des observations faites
sur lui-meme au Bresil par le Dr. Jobert, que les Candirus, v(5ritablos Poissons-sangsues, ne sont
pas, ainsi que le pensait Gunther, de simples commensaux des grands Silurides sur lesquels ils
vivent habituellement; leurs dents et leurs epines operculaires et interoporculaires permettent
non seulement de se fixer sur los branchies de leur bote, mais aussi de faire des blessures amenant
un 6coulomont de sang abondant qu'une disposition spcciale leur permot d'ingurgiter. Enfin a
retat libre, comme la constate le Dr. Jobert, les Vandellies ne craigncnt pas de s'attaquer k
I'Homme, dont elles percent los tc'guments, ce qu'ellcs font aussi certainement sur certains
Mammiferes domestiques. 11 y a lieu en terminant de noter que les dents volumineuses peu
nombreuses, on forme do crochets ac6res de la machoire sup^rieure, sont particulieres au genre
Vandollia, qu'elles sont absentes dans les genres voisins Stegophilus Rcinhardt et Acanthopoma
Liitkon, oil elles sont remplacees par une bande de tres nombreuses petites dents acerees.''

Les Vandellies representent done, chez les Silurides, le dernier terme de la specialisation en
vue d'un parasitisme des plus caractdrises.

That fishes found in the Amazon Valley and called Candirus are a nuisance
is certain. Whether the widely prevalent belief that the Candirii is tropic to
urine, and consequently has a tendency to enter the urethra, or whether the
Candirii's tendency to burrow leads it accidentally to enter the urethra, are all
matters that must for the present remain in debate. A very interesting subsidiary
question is, whether, if Candirus are tropic to urine they do not also enter the

^ While members of the SlegophlUni have bands of minute teeth uniform in size in the upper jaw
there are frequently a few elongate, slender teeth in the middle of the upper jaw, which are similar and
correspond to those of VandeUia.

eigenmann: the ptg.diid^, a family of south African catpishes. 267
urethra of aquatic mammals and of large fishes. Further study may demonstrate
that some s,Kc,es of C andinis have become parasitic in the bladders of large fishes
and aquafc mammals. These are all questions that may legitimately be taken
up by future expeditions.

The first of the commensals or parasites of this family to be described is the
StegopMus ^ns^d^osus of Reinhardt. Roinhardt secured aU of his specimens from
the gills of the giant catfish of the Rio das Velhas, a tributary of the Rio San Fran-
cisco. Haseman secured one specimen of this fish from the sandy island opposite
Januaria, near the mouth of the Rio San Francisco. The fish therefore miy and
does hve in the open as well as in the gill-cavities of larger fishes

The account of StegopMlus insidiosus Reinhardt, given by the author of the
genus and speces, which was published in 1858 (Cf. Nalurhi.tonsk Forenings
V^denskaM^ge Meddelelser, Copenhagen, 1858, reprint, pp. 1-19, Rl H) possesl
great interest. Professor Reinhardt having been repeatediv informed that a large
species of catfish, belonging to the genus Pseudiaty stomas and kno.^ by the natives ^ r^
as Sorub^n, protects its young by carr3ing them in its gills, determined, if possible

ZT '''''""'■ ^ ''''"'' '''"''''"" '^ ' '^^^*^°^ «^ ^^^ ^--^i- i« here

It deeply interested me to ascertain with exactness the circumstances under which this pecu-

se o t llTf ; *1" '':: -^-^ -^"^ *° ™^'°^ *'- ^'°-^ ^* ^^^ *- when they mal
use of It. I therefore offered the fishermen in the vicinity of La.oa Santa, where I was staying at
th time, a good sum if they would bring me a Sorubim with some of its young in the gill v tie'
Finally on February 27, 1852, a fisherman brought me one. in the gill of which he a d tlere
should be a ittle "young one." On examination I indeed found .thL a young fish wdlv an

httle fish looked so unlike the big one that I was astonished, and upon finding out that the 1
fish wa. a male I was strengthened in my doubt as to their relationship. Wh.Ji the sa e fi he

h fi,st, but .^a about three tunes longer, it became clear to me that these two small fishes
cud HI no wise be what it was claimed they were. On the other hand thev recalledTo me th"
picture I earned m my mind of a TricHcnyCeru. which I had obtained one ;ear pr l.slv r m
th Rio das Velhas under the name of Can^teja, or Ba^re .nolle. I natura.h. con lud d i at Z

^::z::^2r '"' 'ti ^'^'•^'' '^^ '-^^'^ - ^^^ ^--^ °^ ^^^« ^ambej! ^i

and houl d , T ;■"'"' '"■"'"■'"• ' ^""'^'^^'"'^•' ^° ^'« ^-^ '^bout this procedure,

and though did not obtain any confession from hun, I nevertheless had no .loubt that I had been
made the victim of a swindle. During the few weeks I still remained in Lagoa Santa bef r t irt-
mg on my homeward journey to Europe, nothing happened to induce me to think otl ^>^ i

comparison bet^veen the supposed young of the Sorubim and the Cambeja, I at once saw that I
had made a mistake m assuming that the former were the young of the hitter. Ji sZt th^se

268 MEMOIRS OF THE CARNEGIE MUSEUM.

so-called young of the Sorubim were the little fishes which I have had the honor of exhibiting to
the Sooioty. The whole matter became more involved and enigmatical to me, because it appeared
that the fisherman, if he had been really guilty of an intcndctl fraud, had for this purpose made
use of a fish which was so rare that I had never found it, although I had collected great quantities
of the various small fishes in the waters around Lagoa Santa; in fact a fish which I was forced to
conclude to be as difficult to obtain as the real young of the Sorubim. In 1854, when I again
visited Brazil, the solution of the riddle was one of my especial aims. Soon after I arrived at
Lagoa Santa in the latter part of November I indeed reached the solution mu(di more quickly
than I had expected, and in the following manner:

A person from (he vicinity of Lagoa Santa, but not the same one, who almost three years
liefore had brought me the first Stegophilus, came to the village on a Sunday in the middle of
December to attend mass according to the custom of the country. He brought with him on this
occasion a Sorubim, which before he went to church he sold to a Frenchman who had a shop in
the town. When mass was over he returned to get his pay, and watched the shopkeeper cut the
fish into pieces. He remarked that when the fish had been pulled out of the water there had been
five yoimg in its mouth, of which two had remained inside. The .shopkeeper looked and actually
found the remaining "j-oung," and was kind enough, as he knew the matter would interest me,
to immediately bring them to me and relate the circumstances.

At the very first glance at the so-called "young" I saw to my surprise that again Stegophili
had been brought inc as the young of the Sorubim. That deception should again be at the bottom
of the matter appeared in the highest degree improbable. It could hardly be thought of, except
upon the assumption that the person who had sold the last Sorubim was in collusion with the
fisherman who tluring my previous stay, three years before, had brought me the first two Steg-
ophili. How could it be explained that both had conceived the idea of passing off the very same
fish as the young of the Sorubim, and that a fish, which has no particular resemblance to the latter?
But, even if there had been collusion, would it not have been more likely that the first party con-
cerned would have come directly to me with his "Sorubim young, " instead of leaving it to be more
or less of a chance whether or not they should fall into my hands? Even if a trick, prearranged
to allay a possible suspicion, were thinkable, nevertheless it was hard to believe that under the
existing conditions the parties involved would have taken the time and the trouble to deceive me,
unless they had expected to reap advantage from their effort. If a trick had been planned in the
present case it was entirely aimless, as no pay was either asked, or given, for these last "young
Sorubim"; and neither the last person, nor any one else, came at a later date to offer me "Sorubim
young." There was therefore left for me no other alternative than to conclude that I had been
unjust in mj' suspicion in the case of the fi.sherman who on the occasion of my previous stay had
brought me the first Stegophili. In other words, this little fish in reality passes into and abides
in the gill-cavities of the Sorubim. Its presence there has through an easily explained mis-
interpretation on the part of the common people given rise in Minas to the story about the
Sorubim's care for its j'oung.

The second species, Branchioica hertonii, known to inhabit the gill-cavities of
larger fishes, is recorded in the present vokimc. It really belongs to the VandelUince.
One specimen was sent me several years ago by Sn. A. de W. Bertoni from Puerto

EIGENMANN: the PYGimiDiE, A FAMILY OF SOUTH AMERICAN CATFISHES. 269

Bertoni, Paraguay. Later he sent me two more specimens, all three having been
taken from the gills of a large characin, Piaractus brachypomus.

Ribeiro, of the National Museum of Rio de Janeiro, caught another very similar
member of this subfamily, Paravandellia, among the water-weeds of the stream near
San Luis de Caceres, in the Upper Paraguay basin.

With fishes as rare as these and as small as these, the question arises whether
two species are really different, or whether the described differences are due to the
fact that one worker uses a hand lens, and the other a binocular dissecting micro-
scope with an arc spot-hght. The results of the two instruments are comparable
to the effects produced by an old-fashioned cannon and a modern forty-two centi-
meter howitzer. BrancJiioica and Paravandellia may prove to be synonymous.

Distribution (Plates XXXVI-XXXIX.)

In considering the distribution of the fresh-water fishes of South America I
found, among other things {Proc. U. S. Nat. Mus., XIV, 1891, p. 18) "that genera
of many species usually have a wide distribution, and convcrsel}^ genera of wide
distribution usually have many six^cies." With one exception the number of
species of any genus of the Pygidiidm varies directly with the greatness of the area
over which it is distributed. Some genera consist of but one species, and that
restricted to but one, or a few neighboring locaUties. As far as known, Eremophilus
is all but confined to the plateau of Bogotd, Scleronema to the center of the Uru-
guay basin, Acanthopoma to a part of the Huallaga basin, Stcgophilus to the Upper
San Francisco basin, Paravandellia to the Upper Paraguay basin, Branchioica to
the Lower Paraguay basin. The genera with more than one species invariably have
a wider distribution. Homodia^tus, with two species, is limited to the lower and
central La Plata basin, Henonemus, with four species, to the Amazon basin, Hakh-
eria, with six species, to the Andes of central and southern Argentina and Chile,
and Pygidium, with sixty-three species, is found in all the mountain streams from
the Tuyra in southern Panama to central Chile and central Argentina, in the moun-
tain streams from Rio Grande do Sul to the Rio Sao Francisco, and sparingly in the
lowlands of Guiana and Brazil. The only exception to the general rule is Och-
macanthus, with three species, ranging from Guiana to Paraguay.

The Pygidiina; are mountain forms, and while they are found in lowlands near
the mountains, we fuid the optimimi in the plains of Bogota and in Lake Titicaca.
They are sometimes the last species to succumb in the struggle with adverse con-
ditions found in high altitudes, and they range further south (to latitude 47° 30' ),
than any other tropical American fishes.

270 MEMOIRS OF THE CARNEGIE MUSEUM.

The Stegophilmo', Vandellimce and Tridentince are essentially lowland forms,
although some species reach considerable elevations.

Chronology.

The first species of the Pygidiidce discovered was taken by Humboldt at Bogota,
and described in 1805 {Recueil d' Observations de Zoologie, etc., pp. 17-19, pi. VI)
as Eremophilus 7nutisii.

The habit of one of the species was next described by Spix in 1829, but attri-
buted to a member of another family. See page 262.

The most prominent genus was first described by Mej'en (Reise, I, p. 475,
Wiegm. Arch. Naturg., 1835, II, p. 269) as Pygidium. I have at diverse times
defended the name, Pygidium, as against the name Trichomydcnis and its varia-
tions.

The various generic names and their present equivalents are given in the fol-
lowing table :

Name Proposed. Proposed in Present Eipiivalent.

Eremophilus Humboldt 1805 Eremophilus Hundioldt.

Thrichomyderus Cuvicr it \'alenciennes 1805 Eremophilus HuinhoUlt.

Trichomyctcrus ValencicMines 1833 Pygidium Meyen.

Vandellia Cuvier & Valenciennes 1846 Vandellin Cuvier & Valenciennes.

Thrychomyderus Cuvier & Valenciennes 1846 Pygidium Meyen.

Thrichomyderus Girard 1855 Pygidium Meyen.

Pareiodon Kner 1855 Pareiodon Kner.

Ccutrophorus Kner 1855 Pareiodon Kner.

Stegophilus Reinhardt 1858 Stegophilus Reinhardt.

Astemoniyderus Guiclienot 1860 Pareiodon Kner.

Pariodon Giinthcr 1864 Pareiodon Kner.

Trachypoma Giebcl 1871 Eremophilus Humboldt.

Tridens Eigenmann & Eigenmann 1889 Tridens Eigenmann & Eigenmann.

Pscudostcgophilus Eigenmann & Eigenmann . . . .1889 Pseudosiegophilus Eigenmann & Eigenmann

Miuroglanis Eigenmann & Eigenmann 1889 Miuroglanis Eigenmann <& Eigenmann.

Acanthopoma Liitken 1891 Acanlhopoma Liitken.

Homodiatus Eigenmann & Ward 1907 Homodimtus Eigenmann & ^Vard.

Henonemus Eigenmann & Ward 1907 Henonemus Eigenmann & Ward.

Hatcheria Eigenmann 1909 Hatcheria Eigenmann.

Ochmacanthus Eigenmann 1912 Ochmacanthus Eigenmann.

Gyrinurus Ribeiro 1912 Ochmacanthus Eigenmann.

Paravandcllia Ribeiro 1912 Paravandellia Ribeiro.

Cobitoglanis Fowler 1914 Henonemus Eigenmann.

Urinophilus Eigenmann 1917 Urinophilus Eigenmann.

Branchioica Eigenmann 1917 Branchioica Eigenmann.

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 271

Location op the Types and Specimens in the Museums of the World.

The species are, for the most part, but little known. Over forty of the ninety-
five recorded species are kno\vn only from the types, which are widely scattered.
Ten or twelve of the types arc in Vienna, two are in Berlin, eleven or twelve in
Paris, eleven in London, one in Torino, Italy, two possibly in Munich, one in the
University of Leipzig, two in Copenhagen, three presumably in Santiago, Chile,
three in Buenos Aires, five in Rio de Janeiro, two in Cordoba, Argentina, one in the
Field Museum, two in the Philadelphia Academy of Sciences, eight in the Museum
of Comparative Zoology at Harvard, eight in Indiana University, twenty-four in
the Carnegie Museum, one in Princeton University. The Carnegie Museum po.S-
sesses forty-six species, Indiana University is next in line with thirty-two species,
and the Museum of Comparative Zoology comes third with twenty species.

The distribution of the known specimens in the various museums of the world
is given in the following table :

S

s

s

3
J^
tg

a
a

a

s
S

S

a

S

3
3

X

a
S
S
a

.1

i

s

a

2

a

.1
la

o

a

3

■a

iz;

a

a
S

3

"3

3

_o

1

a
6

a

a

>

"5

P

i

1

3

>

£

C3

3

O

c

s

S

<

a

a

s

a

1. Nemalogcnys inermis.

type

+

2. Scleronema opercula-

tum

3. Hatcheria palagonien-

type

sis^ •. . . .

type

?

+

+

4. Hatcheria maculata. . .

+

5. " titcomhi . . .

6. " areolatum. .

type

+

+

+

type

7. " burmeisteri.

+

type

8. " macrcei ....

9. Pygidium marmor-

type

+

alum

type?
type?

10. Pygidium palleum . . .

11- " tigrinum. . .

type?

12. " tcnue^

13. " corduvensis^

-1-

14. " ifpeguzzinii.

type

ir). " borellii-' ...

type

+

10. " eichornia-

rum

type

+

' Type in Princeton University.
' Types in C6rdoba, Argentina?
' Types in Mus. Univ. Torino, Italy?

272

MEMOIRS OF THE CARNEGIE MUSEUM.

A

o

n

^o

>.

C3

.a

3

o

a

9

3

s

.1

Oi

S

^a

"1

9
3
08

9

g

a

9

s

a

9

s

9

O

.1

en

■<

x

o

£

s

■s

a

9

9
IS

iz;

1

el

d

S
o
O

a

s

I

a

s

9

3

C

>

1

m

c

P

•a
o

(5

>
'a

2

ai

1

03

9

a

•3
a

a

17.

Pygidium riojanum . .

type

IS.

" helerodon-
lum

type

19.

Pygidium fuscum ....

type

20.

" eigenmanni

type

21.

" vittatum. . .

type

22.

" dispar ....

type

+

23.

" punclula-
luin

type

+

+

24.

Pygidium laczanowskii

type

+

25.

" rivulatutn .

type

+

+

+

+

26.

" poeyanum.

type

27.

fassli

type

28.

" barbouri . .

type

+

+

29.

" oroyw

+

type

+

+

30.

" quechuorum

type

31.

" lalicep^ . . .

type?

+

+

32.

" stellahim . .

+

type

33.

" chapmani .

+

type

34.

" tmnium^. . .

type?

+

+

35.

" caliense . . .

+

type

36.

" latidens . . .

type

37.

" mette

type

38.

" slramineum

+

type

39.

" unicolor. . .

type

40.

" kneri

type

+

41.

" meridcB . . .

type

+

42.

" bogotense . .

+

+

type

43.

Pygidium nigroma-
culaium

type

+

+

+

44.

Pygidium banneaui . .

+

type

45.

" spilosoma .

type

+

46.

" dorsostri-
alum

+

type

47.

Pygidium vemdosum.

type

48.

lalistri-
alum

type

+

+

type

49.

Pygidium striatum

+

50.

" regani ....

type

51.

" retropinne .

type

52.

" guianense .

type

53.

" conradi. . .

+

type

54.

" gracilior . .

type

55.

" amazoni-
cum

type

56.

Pygidium hasemaui. .

+

type

57.

" 7iigr icons. .

type

58.

'.' iheringi . . .

type

+

59.

" zonalum . .

type

60.

" proops....

type

+

61.

" paolence . .

type

62.

" reinhardti .

type

63.

" davisi

type

' Types possibly in Munich.

EIGENMANN: the PYGIDIIDiE, A FAMILY OF SOUTH AMERICAN CATFISHES. 273

s

a

a

CO

9

n

■E

0H

s

M

a

3
V
go

S

o,

a

o
O

a

s

64. Pygidium immacw-

latum

G5. Pygidium vermicu-

latum

66. Pygidium allernalum.

67. " goeldii

68. " brasiliense.

69. " ilatiayw . .

70. " Iriguttalum

71. " punclalis-
siynum

72. Pygidium minulum. .

73. " santa-ritw .

74. Eremophilus mulisii.

75. Parciodun microps . . .

76. Pseudostegophilus

nemurus

77. HomodicBlus anisitsi .

78. " macula-
ius

79. Henonemus macrops .

80. " pu7ictatus

81. " taxis-
tigma

82. Henonemus interme-

dius

S3. Stegophilus insidio-
sus"

84. Acanthopoma an-

nectens'"

85. Ochmacanthus ba-

Irachostoma

86. Ochmacanthus rein-

hardli

87. Ochmacanthus flabel-

liferus

88. Vandellia cirrhosa. . .

89. " plazai....

90. " wieneri . . .

91. " hasemani..

92. " sanguinea.

93. Paravandellia oxyp-

tera

94. Branchioica bertonii .

95. Tridcns mclanops.. . .

96. " brevis

97. Miuroglanis platy-

cephalus

type

type
type

type

type

+

type
?

type

type

type

type

type
type
type

+

+
type

type

+

+

+

type

+
+

type

+

+

+

type

+

type

type

+
+

type
type

type

+

type
+

+

type
type

+
type

type

+

+

+

+

+

+

+

type

+

type
type

+

' Types in Copenhagen.

'" Types in the collection of Professor Leuckhart.

274 memoirs of the carnegie museum.

Sources of the Material Examined.

In 1890 IVIrs. Eigenmann and myself published a revision of the Pygidiidce as
part of the general monograph on the Ncmatognathi of South America (Occasional
Papers California Academy of Sciences, Vol. I, 1890, pp. 316-347). Our account
was based on the material in the Museum of Comparative Zoology, which was col-
lected during the Nathaniel Thayer Expedition to Brazil, 1865-1866, during the
U. S. Naval Astronomical Exi:)edition to the Southern Hemisphere, across the Andes
from Lima, 1849-1852, during the Hassler Expedition at Santiago, Chile, and Callao,
Peru, and during Alexander Agassiz's Exi)edition of 1875 to Lake Titicaca. I have
freely drawn on this monograph, which describes some species, which have not been
duplicated.

From time to time Mr. J. D. Anisits and Sr. A de W. Bertoni have sent col-
lections to Indiana University from Paraguay, containing, among other things,
the types of Homodicetus and Branchioica. Similarly collections were sent from
Sao Paulo by Messrs. Hermann and Rudolph von Ihering.

The collections made by the late J. B. Hatcher for Princeton University were
received and reported upon by me in Vol. Ill of the Reports of the Princeton Uni-
vei"sity Expedition to Patagonia. *

Miss Lola Vance made a small but valuable collection, containing specimens
of Pygidium oroyce, near Tarma, Peru.

The Yale-National Geographic Society Expedition to Peru collected a few
specimens in the Urubamba Valley, which are being reported upon in the Bulletin
of the Museum of Comparative Zoology.

I collected several species in British Guiana, which were described in the
Memoirs of the Carnegie Museum, V, 1912.

Mr. Thomas Barbour collected Pygidium barbouri in the Beni River in Bolivia.

Several specimens, some of them new, were purchased for the collection of
Indiana University from W. F. H. Rosenberg, London.

By far the greater and most valuable collections were secured in Ecuador and
Colombia, and in Brazil, LTruguay, Paraguay and the Argentine.

The collections from Colombia were made by several field-parties. I collected
between Bogota and Buenaventura and at Istmina. Mr. Arthur W. Henn col-
lected between Buenaventura and Istmina. Mr. Henn also collected in the upper
valley of the Patia and southward in the Andes of Ecuador. Mr. Manuel Gon-
zales collected in Colombia along the routes from Bogota west to Honda, north
to Mogotes, and east to Barrigona, securing a wealth of material. Messrs. A. S.
Pearse, M. A. Carriker, Jr., and Alexander Grant Ruthven collected in the Sierra

EIGENMANN: the PYC.IDIIDyE, A FAMILY OF SOUTH AMERICAN CATFISHES. 275

Nevada de Santa Marta for the University of Michigan, and Mr. E. B. William-
son secured si)ecimens forme in the Sierra Nevada, and in other places in Colombia.

Mr. J. D. Haseman, who collected for the Carnegie Museum, secured many
species, especially between the Rio Sao Francisco and Buenos Aires, as well as in
the upper Paraguay' basin and in the Amazon.

At one time or another I have examined all of the seventy-one species pre-
served in American Museums, fifty-eight species in the Indiana University Museum
and the Carnegie Museum being under my immediate charge. Nine of the eigh-
teen known genera and forty-three of the ninety-five known species were described
by me during the course of my study.

I have attempted to collect what is knowTi of the members of the family. I
hope the result will help the next one who undertakes the study of the group and
stimulate the collection of additional specimens and facts of the commensal or
parasitic members of the family.

The Zoological Position of the Pygidiid^.

Phylum PISCES Artedi.

Class TELEOSTOMI Bonaparte.

SuPERORDER OSTARIOPHYSI Sagemehl.

Order PLECTOSPONDYLI Cope.

Family: PygidiidjE Eigenmann & Eigenmann.

Subfamilies :
Nematogenyin^e Gunther.
PYGiDiiNiE Eigenmann & Eigenmann.
Pareiodontin^ Eigenmann.
Stegophilin^ Gunther.
Vandelliin.<e Eigenmann.
Tridentin^ Eigenmann.

Synonymy.
= Siluroidei Trichomycleriformes Bleeker, Nederl. Tijdschr. Dierk., 1, 1863, p. 112.
> Siluridoe Opisthopterce GtJNTHER, Cat. Fish. Brit. Mus., V, 1864, p. 4 and p. 271.

< Siluridce Branchicoloe GDnther, I. c, p. 4 and p. 276.

= Trichotnycteridce Gill, Arrangement of Families of Fishes, 1872, p. 19.

< Pygidiidce Eigenmann & Eigenmann, Am. Nat., July, 1888, p. 649; Occasional

Papers Cahfornia Academy Sciences, I, 1890, p. 316.

< Pygidiidw Gill, Mem. Nat. Acad. Sci., VI, 1893, p. 132.

276 MEMOIRS OF THE CARNEGIE MUSEUM.

< Trichomycteridw Regan, Ann. & Mag. Nat. Hist. (8), VIII, 1911, p. 57.
= Trichomyderidcc Ribeiro, Archives do Muscu Nacional, XVI, 1912, p. 219.

Limits of the family PvcuDiiDiE. (Plates XL and XLI.)

Giinther, in his "Catalogue of the Fishes of the British Mu.scum," V, 1864, pp.
271 277, arranges the then known members of the Pygidiida' imder three "Groui^s,"
belonging to two of his eight Subfamilies of tho' SiluridcE. His seventh Subfamily,
the Silurida' Opisthoptcra', consists of his Fifteentli Group, the Nematogenyina
{HepUiplerus and Nematogenys) and the Si.xteenth Group, the Trichomycterina
{Trichomycterus (= Pygidiwn), Eremophilus, Pariodun). His Eighth Subfamily, the
Siluridce Branchicolce, consists of his Seventcentli Group, the Stegophilina {Stcgo-
philus and Vandellia).

The genus Heptaplcrus^^ included in his Fifteenth Group, was shown by us in
the American Naturalist, July,,18S8, p. 648, to "have no real affinity with the
Pygidiidw."

We do not now feel justified in joining the Cetop,siiur to the family.

The Pygidiida', as here understood, are the Pygidiime (exclusive of Pariolius
and the Stegophilinw of the family, as described by Eigcnmann & Eigenmann, in
the American Naturalist, July, 1888, and Occasional Papers of the California
Academy of Sciences, I, 1890. The species known at the time, thirty-six in number,
belonging to eight genera, were reviewed in the last named paper. The Cetopsince,
included in the pajjers mentioned, constitute a distinct family. Regan {An7i. &
Mag. Nat. Hist. (8), VIII, 1911, p. 574) has united the Pygidiime and Stcgophilince
in his Trichomycterina' of his Trichomycteridw = Pygidiida:. The famih' includes
the South American Nematognaths without an adipose fin, with the dorsal over or
behind the ventrals; i)osterior air-bladder obsolete; the anterior minute, in two
lateral parts, enclosed in bony capsules with a complete osseous floor, united to the
cxoccipital and epiotic bones proximally and to the suprascapula distally; neural
spine of the coalesced vertebrae very low, not as high as that of the vertebrae fol-
lowing them; parapophysis of the vertebrae following the capsule short; skull de-
pressed, entirely closed in front, without an open space between the osseous roof of
the mouth and the ethmoid; vomer and palatines weak, without teeth; clavicles
wide, scoop-shajied, meeting below. The place of the adipose fin sometimes occupied
in part by numerous accessory caudal rays; none of the fin-rays modified into
spines; nares remote from each other, the anterior one frequently provided with
a barbel; the maxillary ending in a short barbel; the lower lip usually ending in

" Related to Heptapkru^ is the genus Phreatobius, for an account of which sec t lie Appendix to this
paper.

e.cenmann: the pvc,d„d«, a famm.v „p sour,, amehkan cateishes. 277
anothor shorter barW just boneath the maxillary l,arl,ol; this lower labial barbel i,
somet,™es ve^- minute and has been ovorlookcl in di^eribing some s « 1 ^
//.™„«and ft„rfas,.„^^^^^^^ and in some species of other genera

Mental barbels, charaeterlstic of many Nematognaths, are lacking exeept in

n all but Ne.na,ooe.y. The o,«reles and interopercles to whieh the ^ iXare
attached are ereefle, and by fia-st erecting those on one side and then thojo th"
other, the fishes are able to "elbow" their way forward in narrow o,.ni„gr unde

Fa^theoT r ■'" ■"'"'' """^ "-^ '''""' »- ""-'*" l» ''^ward.'b tt
Vunddba the opercular spmes point obli<,uely upward and backward, the in ero,x,r
cular spmes downward and backward. mtcroiier-

All of the species secrete a copious ma^ of mucus, and the larger, ones are a.

SPSEUDOSTEGOPHILUS
1 HENONEMUS - 1^

5 HOMOD/ztTUS r-

kP/lRElODON

5ERE/V10PHILUS

hmac/inthus
/•JVandellia

•fliRINOPHILUS

ijParavanoellia

vnva

YrxYnrn Tr\

IfcBRANCHlOICA

4PYGIDIUM

/7Tr;de:ns

nn
/SMlURO&LANlS

primitive of the fa.nily. Tl.e l'u<SZ^^^7 ■^ T ^ '""""'^'"^""^ ='^« "-"louhtedly the most
wo lu.ve ti.e more l.igLy spe ialS ubft i c en ' ' :'''''''''T''' f""-- ''-•^'•'•■-l. Beyond these
nophilous VandMii,!:c. ^^^Mnih^., cuhu.natmg m the parasitic SUgophilinw and the uri-

278 MEMOIRS OF THE CARNEGIE MUSEUM.

slippery as the proverbial eel, which they resemble in other respects. The pectoral
gland is very large in the smaller species.

Key to the Subfamilies and Genera of the Pygidiid^.

a. One ixiir of nicntal barbels, no operculiir or interopercular spines; one barbel at angle of mouth; a
small nasal barbel; pectoral spine iiungeiit; dorsal over ventral.s. { Nemalogenyitur.)

I. Nematogenys Girard.
aa. No mental barbels; opercle and intcroi)ercle with spines; two barbels at angle of mouth; pectoral
spine not pungent.
b. A nasal barbel; mandible with considerable antero-posterior extent, teeth along less than half its
total length; teeth strong; anal short; no mental barbels; opercle and interopercle with
spines; two barbels at angle of mouth; free-living species, some of them of economic
importance. ( Pygidiince.)
c. Opercle with a long dermal flap; maxillary bone longer than the attacherl liarbel; teeth nar-
row incisors" pectoral without a filament; anal short. ..II. Scleronema Eigenmann.
cc. Opercle without a dermal tiap; maxillary very small.

(/. Uorsal long; caudal peduncle subtercte; anal usually entirely under the dorsal; outer

pectoral ray without a filament III. Hatcheria Eigenmann.

dd. Dorsal shorter; caudal peduncle compressed; anal partly or entirely behind the dorsal;
outer ray of the pectoral jirolonged or not.

e. Ventrals present IV. Pygidium Meyen.

ee. No ventral fins; otherwise like Pygidium V. Eremophilus Humboldt.

66. No nasal barbels.

/. Mouth subterminal, the teeth .strong, in a single series; gill-membranes united with isthmus;

anal short. ( Parciodontinw.) VI. Pareiodon Kner,

//. Mouth inferior.

g. Anal short, of 7-1 1 ra3's, its origin usually behind, rarely under that of the dorsal; lower
barbel at angle of mouth minute; eyes superior. Species small, some of them
commensals or parasites.
h. Mouth wide, teeth very numerous, in several very regular series; rami of the lower
jaw transverse, meeting, with teeth along its entire length; premaxillary large.
(Stegophilince.)
i. Accessory caudal rays few, not conspicuous; caudal not fan-shaped nor exces-
sively contracted at base; upper lip with fine, hair-like, movable teeth.
j. Gill-membrane confluent with the isthmus; gill-openings reduced to a
narrow slit in front of the pectoral.
k. Opercle with two spines. VII. . .Henonemus Eigenmann & Ward.
kk. Opercle with four to twelve spines.

I. Caudal deeply forked, the upper lf)be prolonged; eight or nine
spines on the interoi)crcle; color in bands; origin of ventrals
equidistant from caudal and angle of mouth.

VIII. Pseudostegophilus Eigenmann & Eigenmann.

11. Gaudal eniarginate or obliquely rounded, origin of ventrals

nearly equidistant from snout and caudal; color, if present, in

spots IX. Homodiaetus Eigenmann & Ward.

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 279

///. Caudal rounded; few accessory rays; origin of ventrals one-and-
a-half to twice as far from snout as from caudal.

X. Stegophilus Reinhardt.
jj. Gill-membranes united, free from the isthmus . . XI. Acanthopoma Liitken.
. u. Accessory caudal rays very numerous, the tail like that of a tadpcjle; base of
caudal very narrow; no hair-like teeth on the upper lip.

XII. Ochmacanthus Eigenmann.

hh. Mouth narrower, the rami of the lower teeth feeble, not transverse, not meeting in

the middle; teeth few, slender, pointed. ( VanilelUinae.)

m. A few depressible teeth in a single series in the middle of the upper jaw;

mandibles without teeth, or with a few excessively minute teeth on the

ends of the rami; caudal rounded or emarginate

XIII. VandeUia Cuvier & Valenciennes.

XIV. Urinophilus Eigenmann.

mm. A band of depressible teeth in the middle of the upper jaw; a series of much
smaller teeth laterad of the median band; no teeth on the mandible;

caudal forked, the upper lobe longer XV. Paravandellia Ribeiro.

mmm. Two series of depressible teeth in the -middle of the upper jaw; a single
series of much smaller ones laterad of the median series and a claw-like
tooth on the end of the maxillary'- of the median series; two short series
of teeth on the ends of the mandible; caudal subtruncate.

X\'I. Branchioica Eigenmann.
gg. Anal long, with fifteen to twenty-five rays, its origin in front of that of tlie dorsal; eyes
large, lateral; caudal rounded or emarginate. (Tridentinw.)
n. Opercular and subopercular patches of spines distinct ; head greatly depressed, the
eyes infringing on both the upper and lower surfaces of the head; mouth inferior;
a series of fine labial teeth and strong teeth in the jaws; gill-membranes united,
forming a broad free fold across the isthmus; opercle long, slender, ending in a
few thorns; interopercle with similar but smaller thorns.

XVII. Tridens Eigenmann & Eigenmann.
nn. Opercular and subopercular patches of spines confluent; head less depressed;
mouth subinferior; several series of strong teeth in each jaw; gill-membrane
broadly united with the isthmus, without a free margin.

XVIII. Miuroglanis Eigenmann & Eigenmann.

Genus I. Nematogenys''^ Girard.

Nematogenys Girard, Proc. Acad. Nat. Sci. Phila., 1854, p. 198,

Type. — Trichomycterus inermis Guichenot.

Origin of dorsal over or slightly in front of origin of ventrals, near middle of the
body; nasal barbels small; a single maxillary barbel at angle of mouth; a shorter
mental barbel below it; mouth wide, terminal; teeth in a broad band in each jaw;
gill-membranes narrowly joined to the isthmus; first pectoral ray spinous, with

" Possibly the premaxillary. See under the genus.

" viiiia, tA = thread, ykwi, ^ = jaw. In allusion to the maxillary barbel.

280 MEMOIRS OF THE CARNEGIE MUSEUM.

serrse on its posterior margin; anal short; fontanel extending to the base of the
occipital process, with a bridge ()V(>r posterior margin of the eye; opcrcle and inter-
oi)ercle unarmed.

This genus resembles memliers of the PitNcIodirue more than the other species
of the family, and is probably nearer the primitive stock of the family than the
following more highly specialized genera, if it is not a member of the Siluridcc.

Habitdt.—Vhik.

1. Nematogenys inermis (Guichenot). (Plate XLTI, figs. 1, 2.)
Native name "Bagre."

Trichomycterus inermis Guichenot, in Gay, Hist. Ghil. Zo(')l., II, 1848, p. 312;

1854, pi. IX, fig. 2 (Chile).
Nematogenys inermis Girard, Proc. Acad. Nat. Sci. Phila., 1854, p. 198; U. S. Nav.
& Astron. Exped., 1855, p. 240, pi. XXXII (Rio Maypu near Santiago);
GiJNTHER, Cat. Fish. Brit. Mus., V, 1864, p. 272; Philippi, Mb. Ak. Wiss.,
Berlin, 1866, p. 716; Eigenmann & Eigenmann, Proc. Cal. Acad. Nat. Sci.,
(2), II, 1889, p. 50 (Curico; Santiago); Occasional Papers Cal. Acad. Sci., I,
1890, p. 323 (Curico; Santiago); Proc. U. S. Nat. Mus., XIV, 1890, p. 36;
Delfin, Catalogo de los Peces de Chile, 1901, p. 29 (Central Provinces of
Chile); Eigenmann, Reports Princeton Univ. Expcd. Patagonia, III, 1909,
p. 246, pi. XXXI, fig. 2; 1910, p. 398, pi. XXXII, fig. 2.
Nemntogemjs nigricans Philippi, Mb. Ak. Wiss., Berlin, 1866, p. 716.
Nematogenys pallidus Philippi, I. c., p. 716.
Habitat. — Fresh-waters of central Chile.

Head 3.8-4.33; depth 0-7; D. 10; A. 11; P. I, 8; Br. 1 1 12; eye small, superior;
interocular little less than snout; caudal peduncle about as deep as body; origin of
dorsal one-fifth nearer snout than to base of middle caudal rays in specimens 120
mm. long, one-fifth nearer caudal than snout in specimens 260 mm. long; origin of
anal much behind the last dorsal ray; fins all rounded; caudal with numerous acces-
sory rays. Light brown, mottled with darker; a series of about five light areas
along the lateral line; fins speckled.

Genus II. Scleronema^^ Eigenmann. (Plate XXXVI.)

Scleronema Eigenmann, Proc. Am. Philos. Soc, LVI, Jan., 1918, p. 691.

Type. — Scleronema opercidatum sp. nov.

Allied to Pygidinm.

Ventrals nearer snout than to caudal; outer pectoral rays shortest, without a

" aK\-ripc,';= luird. cr/ia, t6 = tlircail, in alliisiim to the hard l>aso of the niaxillarj' barbel.

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 281

filament; opcrclc with a long dermal i\-dp; interopercular spines in a much more
restricted area than in species of Pygidium; accessory rays of the caudal inconspi-
cuous; maxillary barbel with a large osseous base (maxillary). Teeth very narrow
incisors; mouth wide, terminal.

In other respects like Pygidium.

Habitat that of the single species.

1. Scleronema operculatum Eigenmann. (Plate XLIV, fig. 1.)

Sderonema opercidalum Eigenmann, Proc. Am. Philos. Soc, LVI, Jan., 191S, ]). 691.
7077, C. M., type, one, 79 mm.; 7539 a-c, C. M. paratypes, 65-80 mm. Cacequy,

Uruguay basin. Feb. 1, 1909. Haseman.

Head 5.2-5.66; D. 12.5; A. 7.5 counting the rudimentary rays; P. 7; eye in
anterior half of the head ; interocular five times in the length of the head ; width of
mouth nearly half the length of the head.

Nasal barbel short, reaching just beyond posterior nares; maxillary barbel
reaching about half-way to the tips of the opercular spines, the bony base much
longer than the soft filament; a broad, free membrane above from near the anterior
nares to the tip of the osseous base of the barbel, a narrower membrane along the
outer edge of the base of the barbel ; six spines in the main row of the interopercle ;
opercular flap reaching to or beyond base of the last pectoral ray; pectoral about as
long as the head ; origin of ventrals about equidistant from the snout and from the
base of the middle caudal rays: ventrals reaching beyond the anus, not quite to the
anal, equal to the portion of the head behind the nasal barbels; origin of anal under
the posterior part of the dorsal, the distance from the base of its last ray to the
caudal four times in the length ; caudal narrow and long, equal to the length of the
head, its margin slightly oblique, rounded; origin of dorsal over iiosterior half of
ventrals, the distance from the first ray to the caudal 1.3 in its distance from the
snout.

Middle of sides with a series of large spots, similar spots along the back.

Genus HI. Hatcheria'"' Eigenmann. (Plate XXXVI.)

//aic/iOTa Eigenmann, Reports Princeton Univ. Exped. Patagonia, III, 1909, p. 248.

Type. — Hatcheria patagoniensis Eigenmann.

Origin of dorsal behind that of the ventral, which is near middle of the body;
nasal barbels large; two barbels of nearly equal size at the angle of the mouth; no
mental barbels; mouth terminal; teeth conic or narrow incisors, in a few series;

'^ In memory "f .1. H- Tlatelipr, le.ndrr of flic Princeton Univer^;ity K\|)e<litions to Patasonia.

282

MEMOIRS OF THE CARNEGIE MUSEUM.

gill-mombrane free or very narrowly joined to the isthmus; first pectoral ray not
continued as a filament; opercles and interopercles with numerous spines; dorsal

Fig. 2. A-C. Hatcheria patagonicnsis Eigenmann. .4. Skull from above. B. Opercular appar-
atus, etc., as seen from ai)ove when attached to the skull. C. The same spread out flat. D-E. Sclcro-
nema operculatwn Eigenmann. D. Skull from above. E. Opercular apparatus spread out flat. 1,
Premaxillary; 2, ethmoid; 3, lateral ethmoid; 4, nasal; 5, frontal; 6, sphenotic; 7, pterotic; 8, supra-occipi-
tal; 9, epiotic; 10, supraclaviclc; 11, parapophysis of coalesced vertebrae; 12, maxillary; 13, palatine; 14,
metapterygoid ; 15, ciuadratc; 16, pre-oi)ercle; 17, intcropercle; 18, oporclc; 19, hyomandibular; 20, man-
dible.

long, emarginate; caudal peduncle slender, the fin wider than the peduncle, with
few accessory rays; origin and end of anal under the long dorsal, except in H.
areolata.

Habitat. — In the mountain-streams of northern Argentina, central Chile, and
southward. Replacing the species of the genus Pygidium east of the Andes in the
south, and largely also west of the Andes. Its definite boundaries not known.

Key to the Species of Hatcheria.

a. Dorsal with fourteen to seventeen rays.

b. Origin of dorsal equidistant from tip of caudal and some part of the snout; D. 15; last ray of anal
under the last ray of the dorsal or very little farther forward.
c. Distance between anal and caudal 4.5 in the length; origin of ventrals nearer the caudal than
the snout; origin of anal nearer tip of caudal than head; origin of dorsal equidistant from

tip of caudal and posterior nares 1. patagoniensis Eigenmann.

cc. Distance between anal and caudal 3.75 in the length; origin of ventrals nearer snout than to
caudal; origin of anal nearer the head than tip of caudal; origin of dorsal equidistant from
tips of snout and caudal 2. maculata (Cuvier & Valenciennes).

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 283

66. Origin of dorsal equidistant from tip of caudal and occiput.

d. Last anal ray under the dorsal; D. 17 3. titcombi Eigenmann.

dd. Last anal ray behind the last dorsal ray; D. 14. . . .4. areolata (Cuvier & Valenciennes).
aa. Dorsal with twenty-one rays; anal entirely under the dorsal.

e. Ventrals nearer tip of caudal than snout .5. bunneisteri (Berg).

ee. Ventrals nearer snout than tip of caudal 6. macraei (Girard).

1. Hatcheria patagoniensis Eigenmann.
Hatcheria patagoniensis Eigenmann, Reports Princeton Univ. Exped. Patagonia,
III, 1909, p. 250 (Rio Blanco, at base of Andes, latitude 47° 30', longitude 72°
W.; the southernmost record of the family); I. c, 1910, p. 399.
Habitat. — Eastern slope of the Andes between latitudes 47° 30' and 31° 30'.
Mr. Haseman collected the following specimens :

7084, C. M., two, 66 and 82 mm. San Juan, Argentina. Feb. 25, 1909.

7085, C. M., six, 34-77 mm. San Juan, Argentina. Feb. 26, 1909.

11370 and 11371, I. U. M., four, paratypes, 94-120 mm. Rio Blanco: Hatcher.

Fig. 3. Hatcheria patagoniensis Eigenmann. From a paratype in Indiana University.

Head 5; depth 8; D. (13) 15; A. 6. Elongate, slender; caudal peduncle slender,
its depth nearly three times in the head, about four times in its length; upper
maxillary barbel reaching pectoral, lower maxillary barbel reaching to margin of
interopercle ; a broad lobe of skin joining base of lower maxillary barbel to the lower
lip; snout pointed, mouth narrow, its width 3.5 in head, equal to interorbital;
nasal barbels reaching beyond eye; width of head but Uttle less than its length;
greatest width of body behind the pectorals, 1.6 in the length of the head. Gill-
opening not extending forward to below eye; origin of dor.sal equidistant from tip of
caudal and posterior nares; base of dorsal equal to its distance from the caudal, its
free surface emarginate, the anterior lobe rounded, the posterior pointed; beginning
of last third of dorsal not much more than half as high as anterior lobe. Caudal
moderate, emarginate, its lobes rounded, .8 of the length of the head. Anal
broadly rounded, its last ray about under last ray of dorsal. Ventrals broad, their
middle under origin of dorsal, 1.5 in head, equal to height of anal. Base of pectoral
horizontal, closing edgewise to the body, its lower part folded when appressed, its
first ray sickle-shaped, slightly prolonged. Dark yellowish, more or less regularly
spotted with darker; dorsal, caudal, and pectorals irregularly blotched with black.

284 MEMOIRS OF THE CARNEGIE MUSEUM.

Some of the cotypes are more robust in body; in one the anal is blotched like the
caudal; in some the spots form regular series along the sides, leaving lighter stripes
between them.

2. Hatcheriamaculata (Cuvicr & Valenciennes). (Plate XLII, figs. 3-5.)

Trichnmyctcrua marulafus CuviER & Valenciennes, Hist. Nat. Poiss., XVIII,

1S4(), p. 493 (San lago); Guichenot, in Gay, Hist. Ghile, II, 1848, p. 311

(Chile); Gunther, Cat Fishes Brit. Mus., V, 1864, p. 273; Philippi, Mb.

Ak. Wiss. Berlin, 18(50, p. 716 (Chile); Delfin, Catalogo, de lo.s Feces de

Chile, 1901, p. 30.
Thrichomycterus maculatus Girard, Proc. Acad. Nat. Sci. Phila., 1854, ji. 199;

U. S. Naval & Astron. Exped. 1855, p. 243 (Rio Mapocho).
Pygidiian mandaimn Eigenmann & Eigenmann, Proc. Cal. Acad. Bci. (2), II,

1889, p. 51 (Rio Mapocho); Occasional Papers Cal. Acad. Sci., I, 1890, p. 329;

Proc. U. S. Nat. Mus., XIV, 1890, p. 36.
Halrhcrin mnculatn Eigenmann, Reports Princeton Univ. Exped. Patagonia, III,

1909, p. 249, pi. XXXIII, figs. 1, la and lb; 1910, p. 399.

Habitnt. — Pacific slope of Chile.

Head 5.33; depth 7.5; D. 15; A. 9. Elongate, somewhat compressed; head as
long as wide; caudal peduncle long and slender. Eye small, midway between tip
of snout and end of opercle. Lips and lower surfaces of the head thickly covered
with warts. Gill-openings not continued forward to below the eye, the membranes
joined to the isthnuis for a distance equal to one-third the width of the mouth.
Pectorals rounded, the first ray not produced; origin of dorsal in front of the vent,
but some distance behind the ventrals, equidistant from tip of snout and tip of
caudal, its last ray over the last ray of the anal. Caudal long, truncate. Anal
short and high, its height about equal to the length of the caudal, its distance from
the base of the caudal 3.75 in the length. Origin of the ventrals equidistant from
tip of snout and base of caudal, their tips reaching beyond the vent. Back and
sides marbled with light and dark brown; fins pale, immaculate.

3. Hatcheria titcombi Eigenmann. (Plate XLIV, fig. 2.)

Hatcheria titcombi Eigenmann, Proc. Am. Philos. Soc, LVI, Jan. 1918, p. 692.
Pygidium areolatum Evermann & Kendall {non Cuvier & Valenciennes), Proc.

U. S. Nat. Mus., XXXI, 1906, p. 86. (Rio Comajo, tributary of Lake Traful,

tributar.y to Rio LimaJ^)

Habitnt. — Eastern slope of the Andes in Argentina, Limay basin.
11110, I. U. M., one, 164 mm. Arroyo Comajo, J. W. Titcomb.

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 285

This specimen is one of those mentioned by Evermann and Kendall in the
paper quoted above. It differs from P. areolatum as described by Cuvier and
Valenciennes, whose specimen came from Chile, west of the Andes. The origin of
the dorsal is farther back, and its last ray is beyond the last ray of the anal.

Head 6.33; depth 6.5; D. 17.5 (3 and 14.5); A. 9.5, counting the minute im-
bedded rays in each case; P. 9; front margin of the eye in the middle of the head;
interocular a little over three times in the length of the head, oyo three in the inter-
ocular. Teeth verj' narrow chisels ; nasal barbel reaching to above first interopercular
sjiines, maxillary barbel to middle of opercular spines. Pectoral rounded, its first
ray not prolonged, nearly two-thirds the length of the head; origin of the ventrals
equidistant from snout and last fifth of the middle caudal rays; first anal ray under
the sixth dorsal ray, the last anal ray under the fourth from the last ray of the
dorsal; distance between anal and caudal 4.75 times in the length; origin of dorsal
equidistant from tip of caudal and middle of pectorals, its distance from the caudal
two times in its distance from the snout.

Sides without distinct markings; faint traces of longitudinal lines.

This specimen diiTers from a specimen of H. areolata in the Harvard IMu.seum,
in which the last dorsal ray is over the fourth ray of the anal. In a specimen of
areolata in the British Museum drawn by J. Green, the last dorsal VB,y is over the
penultimate anal ray.

4. Hatcheria areolata (Cuvier & Valenciennes).
Native name "Bagre."

Trichomycterus areolatus Cuvier & Valenciennes, Hist. Nat. Poiss., XVIII, 1846,

p. 492 (coast of Chile); Guichenot, in Gay, Hist. Chile, II, 1848, p. 309;

GtJNTHER, Cat. Fishes Brit. Mus., V, 1864, p. 274 (Chile); Philippi, Mb. Ak.

Wiss. Berhn, 1866, p. 714; Delfin, Catalogo de los Peces de Chile, 1901, p. 30.
Pygidium areolatum Eigenmann & Eigenmann, Proc. Cal. Acad. 8ci. (2), II, 1889,

p. 51 (Rio Mapocho, Chile); Occasional Papers Cal. Acad. 8ci., I, 1890, p. 330;

Proc. U. S. Nat. Mus., XIV, 1891, p. 36; ? Berg, An. Mus. Nac. Buenos Aires,

IV, 1895, p. 143 (Arroyo del Tala, Catamarca, Argentina).
Hatcheria areolata Eigenmann, Reports Princeton Univ. Exped. Patagonia, III,

1909, p. 251, pi. XXXIV, fig. 2; 1910, p. 399.
Thrichomycterus maculatus Girard, part; U. S. Naval and Astron. Exped., 1855,

p. 243 (Mapocho).

Habitat. — Pacific slope of Central Chile; ? Catamarca. Argentina.

It is doubftul whether the specimens mentioned by lierg, which had come from

286

MEMOIRS OF THE CARNEGIE MUSEUM.

east of the Andes, belong to H. areolala, the definitely known habitat of which is
the western slope of Central Chile.

Fiii. 4. Halchcria arcolnln (C". & V.) after Kifieiunaiin.
Zu(')l., 103 nun. Mapocho, Chile.

Fidiii ;x specimen in the Mus. Comp.

Head 5.75; depth 8.5; D. 14; A. 8. Elongate, subtercte. Lips and lower sur-
faces of the head thickly covered with small warts. Clill-openings continued for-
ward to below the eye, the membranes free from the isthmus. Upper maxillary
liai-bels reaching to the pectorals. Pectorals rounded, the first ray not prolonged;
origin of dorsal slightly in front of the vent, equidistant from tip of caudal and occi-
put, its last ray over the fourth ray of the anal. Caudal very slightly emarginate.
Distance of anal from the base of the caudal five times in the length. Origin of the
ventrals equidistant from tip of snout and middle of caudal; tips of the ventrals not
reaching the vent. Light brown, with purple longitudinal streaks.

5. Hatcheria burmeisteri (Berg.)

Pygidium burmeisteri Berg, An. Mus. Nac. dc Buenos Aires, IV, 1895, p. 128,

Lam. 2, fig. 1 (Rio Mendoza); Eigenmann, Reports Princeton Univ. Exped.

Patagonia, III, 1910, p. 400.
Trichomyderus burmeisteri Boulenger, Ann. & Mag. Nat. Hist. (7), IX, 1902, p.

336 (Palmira, Rio Mendoza, 900 m.).

Habitat. — Province Mendoza, Argentina, elevation 900 meters.

Known from the type and the specimen recorded by Boulenger.

Reaches a length of at least 260 mm.

Fig. 5. Halchcria hurmeislcri Berg. After Berg.

Head 7.5 (9 in total); depth 9 (10); D. 21; A. 7; P.IO; eye in the middle of the
head; nasal barbel reaching to the eye, maxillary barbel scarcely to gill-opening;
head much longer than broad, depressed; interopercular spines numerous; pectoral

EIGENMANN: the PYGIDIIDyE, A FAMILY OF SOUTH A.MERIC.\N CATFISHES. 287

ray scarcely produced, shorter than head; anal inserted under the eighth dorsal ray;
caudal emarginate, the upper lobe sUghtly produced and jjointed, the lower obtuse.
Color uniform.

6. Hatcheria macraei (Girard.)

Thrichomijcterus macrcei Girard, U. S. Naval and Astron. Exped., 1855, p. 245

(Uspullata, 7,000 feet).
Pygidium macrcei Eigenmann & Eigenmann, Proc. Cal. Acad. Sci. (2), II, 1889,

p. 51 (UspuUatuo*) ; Occasional Papers Cal. Acad. Sci., I, 1890, p. 328; Proc.

U. S. Nat. Mus., XIV, 1891, p. 36; Delfin, Catalogo de los Paces de Chile,

1901, p. 29.
Hatcheria macrcei Eigenmann, Reports Princeton Univ. Exped. Patagonia, III,

1909, p. 248, plate XXXII, figs. 1, \a and \h; 1910, p. 399.

Habitat. — Eastern slope of the High Andes of central Chile.
7458a-j, C. M., 24-113 mm. San Juan, Argentina, Feb. 25, 1909, Haseman.
7549a-/, C. M., 37-70 mm. Rio Colorado, March 5 and 6, 1909, Haseman.

Fici. 6. Hatcheria macraei (Girard). After Eigeumuuii. Iruin Mo. 8298, Mus. Comp. Zool.,
Uspullata, Chile.

Head 6.5; depth 7; D. 21 or 22, rarely 20 or 23; A. 10. Elongate, rather com-
pressed, especially backward. Head nearly or quite as broad as long, snout rounded ;
eye small, midway between tip of snout and end of opercle; none of the barbels
reaching the gill-opening. Gill-opening scarcely continued forward, joined to the
isthmus for a distance equal to half the width of the mouth. Pectorals obliquely
truncate, the first ray not produced in the type, or slightly produced in the si>eci-

* 7 A misprint for Uspullata? " UspuUatuo " is not found in gazetteers or on maps. Editor.

288 , MEMOIRS OF THE CARNEGIE MUSEUM.

mens collected by Haseman; origin of dorsal some distance behind ventrals, equi-
distant from occiput and tip of caudal in the type or from some portion of the snout
and tip of caudal in the specimens collected by Haseman; fourth or fifth dorsal ray
highest, then gradually decreasing in height to the last. Caudal emarginate, the
upper lobe pointed, the lower rounded; anal inserted about under the ninth dorsal
ray and terminating under about the seventeenth; ventrals inserted nearer tip of
snout than to tips of middle caudal rays, reaching to the vent or shghtly beyond.

Sides and back in the San Juan specimens profusely spotted, much less so in
the specimens from the Rio Colorado.

Genus IV. Pygidium'" Meyen.

Tricliuiiiijclcruii \'alenciennes, in Humboldt, Rec. d'Obs. Zool. et Anat., II, 1833,

p. 348 (nigricans) ; not Tlirichomyderus Cuvier and Valenciennes, in Humboldt,

of which it is a misspelling. Gijnther, Cat. Fishes Brit. Mus., V, 18G4, p.

272.

Thnjchomyderus Cuvier & Valenciennes, Hist. Nat. Poiss., XVIII, 1846, p. 485

(misspelled).
Thrichomyderus non Cuvier & Valenciennes, Girard, Proc. Acad. Nat. Sci. Phila.,
VII, 1854, p. 198; Girard, U. S. Nav. Astron. Exped., II, 1855, p. 242 (mis-
quoted).
Pygidiuin Meyen,'' Reise, I, 1S35, p. 474 [J'uscain).
Type. — Pygidium fuscum Meyen.

Skin naked; head depressed, nearly or quite as broad as long, its length
five or si.\ times in the length from snout to caudal; body terete, the caudal
peduncle compressed, deep; a nasal barbel as long as the head or shorter, on the
posterior edge of the anterior nares; two barbels at the angle of the mouth, the
upper, connected with the rudimentary maxillary, may reach to the tip of the

'^ TTvyibiov, TO = a thin rump = the tail nuicii com pressed.

"In "Archiv fiir Naturseschichtc von Dr. Ar. Fr. Aug. Wiegmann, Zweiter Band, Berlin, 1S35
(Part. 11), p. 2()9," the original description with addenda appears as follows:

"Einc neuc Gattung der Siluriden, Pygidium, hat Meyen (Reise, I, p. 475), nach cincni todten
Fische aufgcstellt, den or in einem klcinen Bache Peru's antraf.

"Char. gen. Corpus elongatum, caudam versus conipressuni. Cirri maxillares 4, nasales nuUi.
Pinna' pectorales ut pinna' abdominales du;r cum pinna anali circa auum positK. Pinna adiposa parva.
(Die einzigc Art P. fuscum ist 5^G" lang). Die Gattung bedarf einer genaucren Charakteristik; die
gegebenc ist dahin zu bcrichtigen, dass cirri nasales vorhanden sind, und die Riickenflosse Strahlen hat,
also koine Fettflosse ist. Die Gattung steht demnach nicht Malapterus, sondern ,Silurus nahe, unter-
scheidet sich von dicsem ilurch Zahulosigkeit des Vomer, (lurch ein operculum aculeato-serrcUum, und
durch die weit hintcn stehende Riickenflosse. Das Exemplar ist im Berliner Museum."

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 289

pectoral, but is usually shorter; no mental barbels; eye small, in the middle of the
head, or just in front of the middle, without a free orbital rim; interopcrcle with
numerous spines in several series, those of the outer series largest (in the very young
in a bunch as long as the opercular bunch, in the older in a much larger patch) ;
opercle with a bunch of similar spines; gill-membranes narrowly united with the
isthmus and usually with a narrow, free margin across it; mouth of moderate width,
terminal, the jaws with two or more series of chisel-shaped or conic teeth; no teeth
on lips or on the vomer; fins without spines, the pectoral short, the outer, simple
ray usually prolonged into a filament extending distinctly beyond the rays; ventrals
small, placed in the middle or considerably behind the middle of the body; anal
short, usually in- part below, more rarely behind, the dorsal; caudal short, broadly
rounded, truncate or slightly emarginate, accessory rays variable, sometimes very
conspicuous, sometimes much less so; origin of the dorsal between the vertical from
the origin of the ventrals and anal, always nearer the base of the caudal than to the
snout; the fin is low, rounded, short, with a variable number of rays up to twelve.
Cuvier & Valenciennes state that the first ray of the dorsal of P. nigricans is pro-
longed in a filament. Is this a lapsus digiti for first ray of the pectoral? The
dorsal and anal have from two to four minute accessory rays entirely hidden in the
thick skin in front of the evident portion of these fins.

The color may be uniform, or there may be one or three longitudinal stripes
or rows of spots, or large spots less regularly arranged, or numerous small spots
which may be discrete, or which may coalesce into vermiculations. There are no
distinct cross-bars. If the markings are longitudinally arranged, a series of spots
may be replaced by a stripe or nice versa in different individuals of the same species.

Some of the species are of very small size, the maximum recorded size is 350
and 390 mm. in P. rivulalum and P. taczanowskii from Peru.

The eggs reach 2.5 mm. in diameter.

The species differ from each other largely in the shape of the teeth, the length
of the barbels, the relative position of the dorsal, anal, and ventrals, and in the
color.

Distribution. — The members of the genus Pygidium belong ixirticularly to the
mountains, where they live in all waters from small rills to large lakes like Titicaca.
They are frequently found under rocks or buried in the muddy banks of streams.
They extend from Panama southward to C'hile and Patagonia, where they arc
replaced by the members of the allied genus Hatcheria. In favorable places they
descend to the sea, as at Jequetepec and Callao, and they are among the last or are
the very last to disappear in ascending the mountains, where they are associated

290 MEMOIRS <)P^ THE CARNEGIE MUSEUM.

with a few other mountain forms Uke Grundulus at Bogota, Astroblepus and Bry-
conamericus in the High Andes from Panama to Cuzco, and Oresteas in Lake Titi-
caca. The only fish found by Haseman in the headwaters of the Rio das Velhas
was a member of this genus. Species of Pygidiutn were found in the most elevated
places visited by Henn in Colombia and Ecuador. In Titicaca they are of con-
siderable economic importance, and on the plains of Bogota, the nearly related
genus Eremophilus is of prime economic importance. They are found in Guiana
and in the Amazon, but only as dwarfs. They also flourish in the mountain-
streams of southeastern Brazil, but the species do not reach the size of those in
Peru. Some of the species are found on both slopes of the Andes, but, unlike low-
land species of other fishes, which if found on both sides of the Andes, usually have
a very wide distribution, the species of the genus Pygidhmi all have rather limited
ranges. Many of them are restricted to a single small river and no river has many
species. In 1910 I said (Patagonia Report, p. 248), "There is no place on record
harboring more than one species of this genus." This statement requires modifica-
tion. While, so far as known, many basins contain but a single species, a number
of other smaller rivers, the Iguape for instance, contain several. Judging by its
wide distribution, both horizontally and vertically, the genus is probably one of
very long standing.

The species of the genus need a careful revision, but the descriptions usually
omit mention of the character of the teeth, and no collection contains any great
percentage of the total number of si)ccies described. Furthermore, judging from
the fact that they are abundant in all the high mountain-rills and even in lowland
rapids, and that from the stretch from Caracas along the eastern slope of the
Andes to Peru we have only the types of the species P. meridce, kneri, meice, and
dorsostriatum, the revision of the entire genus may be left in abeyance. The species
are grouped according to the areas from which they have been reported.

CHILEAN SPECIES

The species from Chile where the members of the genus Hatcheria have in part

replaced them, are P. marmoratum (Philippi), P. palleum (Philippi), and P.

tigrinum (Phihppi).'^

1. Pygidium marmoratum (Phihppi).

Trichomyderus marmoratus Philippi, Mb. Ak. Wiss. Berlin, 1866, p. 714; Eigen-
MANN & EiGENMANN, Occasional Papers Cal. Acad. Sci., I, 1890, p. 326;
Delfin, Catalogo de los Peces de Chile, 1901, p. 31.

" In addition to the three species described bj' Philippi, Pygidium nigricans (Cuvier & Valencien-
nes) is recorded from Chile by Gay. This is probably an error.

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 291

Pygidium marmoratum Eigenmann & Eigenmann, Proc. U. 8. Nat. Mus., XIV,
1891, p. 36; Eigenmann, Reports Princeton Univ. Exped. Patagonia, III,
1910, p. 399.
Habitat. — Chile.

Blackish gray, marbled with many black spots, as in punctatum; fins dark.
Depth 10.82; D. 10; A. 6.

2. Pygidium palleum (Philippi.)

Trichomycterus palleus Philippi, Mb. Ak. Wiss. Berlin, 1866, p. 715; Eigenmann &

Eigenmann, Occasional Papers Cal. Acad. Sci., I, 1891, p. 325; Delfin,

Catdlogo de los Peces de Chile, 1901, p. 30.
Pygidium palleum Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., XIV, 1891,

p. 36; Eigenmann, Reports Princeton Univ. Exped. Patagonia, III, 1910, p.

399.

Habitat. — Chile.

Light reddish; fins colorless; head 6.5 in total; D. 9-10; A. 6.

3. Pygidium tigrinum (Philippi).

Trichomycterus tigrinum Philippi, Mb. Ak. Wiss. BerUn, 1866, p. 714; Eigenmann

& Eigenmann, Occasional Papers Cal. Acad. Sci., I, 1890, p. 326; Delfin,

Catalogo de los Peces de Chile, 1901, p. 31.
Pygidium tigrinum Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., XIV, 1891,

p. 36; Eigenmann, Reports Princeton Univ. Exped. Patagonia, III, 1910,

p. 399.

Habitat. — Chile.

Light with reddish points; fins immaculate; head 6.5; depth 6.5 in total length;
D. 9 or 10; A. 6.

Members of the genus Pygidium have been recorded from the mountains of
Argentina, north of the latitude of Buenos Aires. South of this latitude species
of Hatcheria take their place.

Key to the species of Pygidium from Argentina and the Paraguay Basin

a. Teeth pointed (not cx.imined in teiuie).

b. Plain yellowish, eyes luid barbels black; head triangular; opercle and pre-opercle well armed;

body mucli compressed; D. 6; A. 5 4. tenue (Weyenbergh).

66. Back spotted, sides with a band.

c. Pectoral ray prolonged; head as wide as long, 4.66-5 in the length; eye very small, a little in
advance of middle of head, its diameter three in the interorbital; maxillary barbel reaching
pectoral; depth of caudal peduncle half its length; origin of dorsal behind the ventrals,
its distance from the caudal two and one-half in its distance from the snout; origin of

292 MEMOIRS OF THE CARNEGIE MUSEUM.

viMitrals o(iuiilist;iiit from siumt and tip of cauilal, or a little nearer the latter; caudal
trunciitc, or i^lightly eniarginate; olive above, more or less distinctly siiotted with brown; a
blackish band from opercle to the caudal; D. 8 or 9; A. (i .... 5. corduvense (Weyenbergh).
cc. Pectoral ray not prolonged; body and head tuberculate; head 6.5-7.5 in the length (with the
caudal); eye a little in advance of the middle of the head; maxillary barbel broad and short;
teeth minute, in many series; 6-S spines in the main row of the interopercle; tins small;
posterior part of dorsal over anal; caudal subtruncate or rounded; D. 3 + 8; A. 3 + 6.

('). spegazzinii Berg.

bbb. Back witii sjjots; no lateral band; maxillary barl)el reaching origin of the i)ectural or farther;

distance between origin of dorsal and caudal 2.5-3 in the distance between dorsal and

snout; origin of ventrals equidistant from snout and tip of caudal.

(/. Pectoral ray not prolonged; head 5.33-5.5; eye in middle of the head, 3 in interorbital; origin

of anal under end of dorsal; caudal truncate; D. 10; A. 7. Spots of back large, round.

7. borellii (Boulenger).

(/(/. Pectoral ray much prolonged; head si.\ times in the length; eye entirely in anterior half of

the head; origin of anal nearly under origin of dorsal; caudal rounded; back, sides, dorsal

and caudal densely spotted 8. eichorniarum Ribeiro.

(jrt. Teeth in part, at least, incisors; head as long as l)r()ad; barbels short; first pectoral ray prolonged.

e. Head 8.5 in the length with caudal; eye in anterior half of head, 1.5 in the interorbital; dorsal
obliquely truncate, its po.sterior third over the anal; caudal truncate; D. 2 + 9; A. 1+6; faint

spots _. 9. riojanum Berg.

ee.. Head six times in the length without the caudal; eye in middle of the head; thirteen .spines in the
main row of the interopercle; caudal emarginate; D. 4 + 6.5; X. 2 + 5.5; nasal barbel extending
to posterior margin of the eye 10. heterodontum Eigeumann.

4. Pygidium tenue'^ (Weyenbergh). (See fig. 7, p. 293.)
Trichomycterus tenuis Weyenbergh, Act. Acad. Nac. Cienc. Exact., Cordoba, III,

1877, p. 12, pi. Ill (Sierra de CY)rdoba, near Cruz del Eje); Eigenmann &

Eigenmann, Occasional Papers Cal. Acad. Sci., I, 1890, p. 326.
Pygidium tenue Eigenmann & Eigenmann, Proc. U. S. Nat. Mas., XIV, 1891,

p. 36; Eigenmann, Reports Princeton Univ. Exped. Patagonia, III, 1910,

p. 399.

Habitat.— li\o Prime ro, Cordoba.

Yellow, eyes and barbels black; head triangular; opercle and pre-opercle well
armed. Body much compressed; D. 6; A. 5.

5. Pygidium corduvense (Weyenbergh).
Trichomycterus cunluoensis ^^'eyenbergh, Act. Acad. Nac. Cienc. E.xact. Cordoba,
III, 1877, p. 11, pi. Ill (Rio Primcro); Eigenmann & Eigenmann, Occasional

" Berg (An. IMus. Nac. Buenos Aires, IV 1895, p. 144) makes this a synonym of Halcheria areolata.
Boulenger (Boll. Mus. Zool. Anat.Comp. Univ. Torino, XII, 1897), contends that Weyenbergh is right
in placing it near P. dispar.

EIGENMANN: the PYGIDIID/K, a family of south AMERICAN CATFISHES. 293

Papers Cal. Acad. Sci., I, 1890, p. 320; Boulengeu, Boll. Mus. Zool. Anat.
Comp. Univ. Torino, XII, 1897 (Caiza).

Fig. 7. Pijgidlum tame (Weyoiil)crf!;li). After Wuvt-iibfigli.

Pygidium corduvense Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., XIV, 1891,
p. 36; Eigenmann, Reports Princeton Univ. Exped. Patagonia, III, 1910,
p. 399.

Fiu. 8. Pygidium corduvense (Weyenbergh). After Weyeubergli.

294 MEMOIRS OF THE CARNEGIE MUSEUM.

Habitat. — Sierra do Cordoba, near Cruz del Ejc, Aroentina; Caiza, Bolivian
Chaco.

The following is from Boulengcr's description of specimens up to 62 mm. long:
" Head 4.66-5; D. 8-9; A. 6; eye three times in interorbital, a little nearer snout
than to opercle; maxillary barbel reaching pectoral; caudal peduncle twice as long
as high; distance between origin of dorsal and caudal two and one-half times in the
distance between dorsal and snout; outer pectoral ray prolonged; origin of ventrals
equidistant from snout and tip of caudal, or a little nearer the latter; caudal trun-
cate, or slightly emarginate. A dark lateral band."

6. Pygidium spegazzinii Berg.
' Pijgidiwn .spegazzinii Berg, An. Mus. Nac. Buenos Aires, V, 1897, p. 267; Eigen-

mann. Reports Princeton Univ. Expcd. Patagonia, III, 1910, p. 399.

Habitat. — Rio de Cachi, Province de Salta, northern Argentina, 2,500-2,800 m.

Known only from the types, 29 specimens, the largest of which is 95 mm., in
the National Museum of Buenos Aires.

Head 6.5-7.5 in the length with the caudal; D. 11 (3 + 8); A. 9 (3 + 6); eye
much nearer snout than to edge of opercle; nasal barbel extending beyond the eye,
maxillary barbel short and broad; gill-membrane without free margin at the middle;
teeth in many series; interopercular spines few, in three or four rows, the sixth to
eighth in the lower row moderate in size ; opercular spines also few and minute ; body
verrucose; pectoral obliquely rounded, its first ray not prolonged; anal inserted
under i^osterior part of dorsal; caudal sublTuncate or rounded.

7. Pygidium borellii (Boulenger).
Trichomyderus borellii Boulenger, Boll. Mus. Zool. Anat. Comp. Univ. Torino,

XII, 1897 (Mission d'Aguairenda; Tala; Lesser); Ann. & Mag. Nat. Hist.

(7), IX, 1902, p. 336 (Pahnira, Rio Mendoza).
Pygidium borellii Eigenmann, Reports Princeton Univ. Exped. Patagonia, III,

1910, p. 400.
Pygidium schmidti Berg, An. Mus. Nac. Buenos Aires, V, 1897, p. 266 (Rio de

Belen, Prov. Catamarca, Argentina); Eigenmann, I. c, p. 399.

Habitat. — Mission d'Aguairenda, Bolivian Chaco; Tala and Lesser, Province
Salta, northern Argentina; Rio de Belen, Province Catamarca, northern Argentina;
Palmira.

Reaching a recorded length of 110 mm.

Head 5.35-5.5; D. 10; A. 7; eye very small, in middle of the head, three times
in the interorbital; bod}' compressed, caudal peduncle one and one-half times as

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 295

long as high; maxillary barbel reaching pectoral; origin of anal under end of dorsal;
distance of origin of dorsal from caudal two and one-half to three in its dis-
tance from the snout; pectoral ray not prolonged; origin of ventrals equidistant
from tips of snout and caudal; caudal truncate; sides and back with large dark
spots.

8. Pygidium eichorniarum (Ribeiro). (Plate XLIV, fig. 3).
Trichomycterus eichorniarum Ribeiro, Comm. Linhas Telegraphicas Estrategicas

Matto-Grosso ao Amazonas, Annexo, 5, 1912, p. 27 (C^aceres).

Habitat. — U])per Paraguay.

Evidently allied to P. riojanum, pi'oups, and metce.

Known from the types, two specimens, the larger 44 mm., and
7556a-c, C. M., 24-30 mm. Caceres, May 27, 1909. Haseman.
7557rt & b, C. M., 33-43 mm. Caceres, May 23, 1909. Haseman.
7558a, C. M., 42 mm. San Francisco, Rio Jauru, Paraguay basin, June 10, 1909.

Haseman.
7559a, C. M., 32 mm. Bastos, Rio Alegre, eight miles south of Villa de Matto-
Grosso, June 26, 1909. Haseman.
7560a-c, C. M., 39-41 mm. San Antonio, Rio Guapore, plantation of Maciel,

July 31-Aug. 11, 1909. Haseman.

Head 5-5.75; D. 9-10; A. 8; P. 6; posterior margin of eye shghtly in advance
of the middle of the head; eye about 1.5-2 in the snout, 5.5-6.5 in the head, about
equal to the interorbital; maxillarj^ barbel reaching to axil or middle of pectoral;
nasal barbel to the tip of the opercular spines or the axil of the pectoral; teeth
conical, a very narrow band of but two or three irregular series; origin of ventrals
equidistant from tip of snout and tip of caudal; origin of anal under, or but slightly
behind, the first dorsal ray; distance from base of last anal ray to base of caudal
about six times in the length; distance from origin of dorsal to base of caudal two
and three-quarters in its distance from the snout; caudal rounded, accessor}' rays
moderate; first pectoral ray much prolonged, with its filament nearly equal to the
length of the head.

General color of P. brasiliense, back and sides profusely spotted; caudal rays
with numerous spots, dorsal and anal less profusely spotted.

9. Pygidium riojanum Berg.
Pygidium riojamim Berg, Ann. Mus. Nac. Buenos Aires, V, 1897, p. 269; Eigen-
MANN, Reports Princeton Univ. Exped. Patagonia. HI, 1910, p. 399.
Habitat. — Arroyo in the Gordillera dc la Rioja, northern Argentina.

296 MEMOIRS OF THE C.\RNEGIE MUSEUM.

Known from the type, a specimen 85 mm. loiiii', in the National Museum at
Buenos Aires.

Head 8.5 in the length witli the caudal; D. 9 (2 + 7); A. 7 (1 + 0); eye 1.5 in
the snout, 1.5 in interorbital, 2.5 in jwsterior part of the head; nasal barbel scarcely
extending beyond the eye ; maxillary barbel scarcely to end of opercle ; gill-membrane
with scarcely a free margin; interopercular spines in two or three series, medium in
size; \vcih small, in irregular series, anterior ones larger, their tips broader; fins
small: first pectoral ray prolonged; anal under last third of dorsal; caudal truncate.

10. Pygidium heterodontum Eigenmann. (Plate XLIV, fig. 4.)
Pygidium heterodoiihim Eigenmann, Proc. Am. Philos. Soc, LVI, Jan., 1918, p.

G92.
13832, I. U. M., 83 mm., 9, Rio INIendoza, Palmira, Argentina, 900 m. Purchased

from Rosenberg.

Palmira is probably the southernmost locality on the eastern slope of the
Andes from which species of this genus have been taken.

Head six times in length, as long as broad; D. 10.5 (4 + 6.5) ; A. 7.5 (2 + 5.5);
P. 9; eye in middle of the head, interocular 3.5 in the head; teeth in three series in
each jaw, those of the outer row narrow incisors, of the second row much smaller
incisors and of the third row conic. Head much depressed, interopercular spines
numerous, thirteen in the last row.

Nasal barbel extending to the posterior margin of the eye, maxillary barbel to
the base of the opercular spines; first jiectoral ray scarcely produced, equal to the
portion of the head behind the posterior nares; origin of ventrals midway between
opercle and caudal, reaching to the vent; origin of anal under posterior part of the
dorsal, the distance between its last ray and the base of the middle caudal ray 4.4
in the length; depth of the caudal peduncle 2.5 in its length; caudal narrow, cmargi-
nate, a little more than five in the length; origin of dorsal midway between the tip
of the caudal and the occiput, over the tip of the ventrals, its distance from the
caudal 1.75 in its distance from the snout.

A faint lateral band and obscure spots or marblings.

The members of the genus Pygidium reach their largest size and greatest
economic importance in Peru. The Carnegie Museum has no specimens from this
region, excejit P. oroyce Eigenmann & Eigenmann. To the key below should be
added P.fuscum INIeyen, the type of the genus.

Key to the Speties of Pyc.idium from Peru and Western Bolivia.
a. Pectoral ray prolonged.

b. Dorsal entirely in front of the ;in,il.

c. Caudal truncate or roiuidod. •

EIGENMANN: the PYGIDIID/E, a family of south AMERICAN CATFISHES. 297

d. Uniform brown, darkest on the back; head flat above; width of head less than its length;
barbels scarceij' extending beyoiul tlie eyes, which are in the middle of the head; a
jjroad band of villiforin teeth in each jaw; first pectoral ray but slightly prolonged;
origin of dorsal equidistant from tip of caudal and nares, over posterior edge of base of
ventrals; last ray of the dorsal over the origin of the anal; caudal rounded, distance
between anal and caudal 4.5 in the length; ventrals nearer tip of snout than to tip of

caudal; head 'i; dcptli "i.tKi; 1). 10; A. 9 12. eigenmanni (Boulenger).

(111. Head and body witli dark sjjots; a dark lateral stripe; head as broad as long; barbels
etpial to eight-tenths the length of the head; snout slightly sh<jrter than the postor-
liital part of the head; outer jieotoral ray as long as the head, longest branched ray
three-quarters as long; origin of dorsal in advance of the vent, its distance from the
base of the caudal one and one-half times in its distance from the snout; origin of anal
slightly behind the last dorsal ray; caudal truncate; distance between anal and
cauilal 4. .5 in the length; head ().2.5; D. with six, A. with four branched rays.

l.'i. vittatum (Regan).
cc. Caudal eniarginate.

e. Back and sides profusely spotted; head longer than broad; barbels not quite reaching gill-
openings; origin of ventrals equidistant between tiji of snout and tip of caudal;
head 5.2-5.66; D. 12; A. 9 or 10.
/. Sides, back, dorsal, and caudal with large spots; spots as large as, or larger than, the
eye, smallest on the head; origin of dorsal equidistant from tip of caudal and
anterior margin of eye; distance between anal and caudal five or six times in the

length 14. dispar Tschudi.

//. Spots mi.cli smaller than the eye; origin of dorsal equiuis^tant from tip of caudal and
a pi}int between occiput and anterior margin of the eye; distance between anal

and caudal 6-6.5 in the length 15. punctulatum (Ctivier & Valenciennes).

cc. Back and sides unspotted; maxillary barbel reaching past origin of pectoral; origin of
dorsal varying with age; origin of ventrals a little nearer snout than to tip of caudal;
distance between anal and caudal five times in the length; head 4.66-5.5; eye minute,
in adult a little behind the niidillc of the head; teeth conic.-"

16. taczanowskii (Steindachner).
bb. Dorsal in part over the anal.

g. Accessory caudal rays conspicuous; caudal rounded; outer row of teeth narrow incisors;
maxillary barbel reaching edge of pre-opcrde; origin of dorsal equidistant from tip of
caudal and a point between occiput and posterior nares; distance between caudal and
anal 4.4-4.5 in the length; head 4.5-5.5; D. 13; A. II.

17. rivulatum (Cuvier & \'alenoiennes).

gg. As under g, but "dilTering in its large, dark blotches." IS. poeyanum it'ope).

ggg. Accessory caudal rays not evident; caudal emargin.-itc; tcctli cji.ic; head 4.66; depth 7;
D. 8; A. 6; eye in middle of the head; head longer than wide; nasal barbels reaching
posterior margin of the eye; maxillary barbel to the gill-o])ening; distance between dorsal
and caudal about 2 in its distance from the snout; distance between anal and caudal 5.5.

19. barbouri Eigenmann.
gggg. Acccs.sory caudal rays not conspicuous, the caudal truncate; teeth conic; head 4.85; depth

'" The male of diapnr as figured liy Tsehudi agrees with this.

298 MEMOIRS OF THE CARNEGIE MUSEUM.

6; D. 9; A. 7; ej'e in midille of the head; head a little longer than wide; nasal barbels
reaching lateral end of head, maxillary barbel a little beyond origin of pectoral.

20. fassli Steindachncr.
aa. Pectoral ray not prolonged; end of dorsal about over the middle of the anal; caudal rounded; head as
long as wide; sides and back with irregular spots.
h. Eye moderate; origin of the dorsal over or in front of the vent, equidistant from eye and tip of

caudal or nearer the latter; head 5.75-6; D. 12; A. 10 21. oroyae Eigeninann.

hh. Eyes very minute; origin of the dorsal in front of the vent, nearer the eye than the tip of the
caudal; head 5; U. 8; A. 6 or 7 not counting the hidden rays; a dark lateral line.

22. quechuonim Steindachner.

11. Pygidium fuscum Mcyen.
Pyyidium fuscuin ^Ieyen, Reisc, I, 1835, p. 475; Wiegmann's Arch., 1835, II, p.
269; EiGENMANN & EiGENMANN, Occasional Papers Cal. Acad. Sci., I, 1890,
p. 325; Proc. U. S. Nat. Mus., XIV, 1891, p. 36; Eigenmann, Reports Prince-
ton Univ. Exped. Patagonia, III, 1910, p. 399.
Habitat. — Peru.

Very little is known about this species. It was imperfectly described by Meyen.
Fortunately the type which was found dead in some stream in Peru, is in the Berlin
Museum (fide Tschudi, Fauna Peruana, Ichthj'ologie, 1845, p. 21). Tschudi
tells us that fiiscmn is specifically distinct from his own sj^ecies dispar. This and
the original description is all we know about the species.

12. Pygidium eigenmanni (Boulenger).
Pygidium knerii Eigenmann & Eigenmann {non Steindachner), Occasional Papers

Cal. Acad. Sci., I, 1890, p. 335 (Cumbaca).
Trichomycterus eigenmanni Boulenger, Boll. Mus. Zool. Anat. Comp. Univ.

Torino, XIII, Dec. 2, 1898, substituted for P. knerii Eigenmann & Eigenmann,

non Steindachner.
Pygidium eigenmanni Eigenmann, Reports Princeton Univ. Exped. Patagonia,

III, 1910, p. 400.

Habitat. — Cumbaca. Location on map not known.

Boulenger based his eigenmanni on the description of P. knerii Eigenmann &
Eigenmann, which, according to Boulenger, was based on a specimen distinct from
knerii. The species is known from the description of a specimen 110 mm. long from
Cumbaca, collected by the Thayer Expedition and now at Cambridge, Mass.

Head 5; depth 5.66; D. 10; A. 9. Elongate, compressed; head greatly de-
pressed, flat above, the eyes entirely superior; width of the head less than its length.
Barbels scarcely extending beyond the eyes, which are equidistant from tip of snout
and end of opercle. A broad band of vilUform teeth in each jaw. Pectoral rounded,

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 299

the first ray slightly prolonged. Origin of dorsal above posterior edge of base of
ventrals, equidistant from tip of caudal and nares, the last ray over origin of anal.
Caudal rounded, its distance from the anal 4.5 in the length. Ventrals nearer tip
of snout than tip of caudal. Uniform brown, darkest on the back.

13. Pygidium vittatum (Regan).
Trichomijderus vittatus Regan, Ann. & Mag. Nat. Hist. (7), XII, 1903, p. 623 (Col-
lected bj' Ockenden).
Pygidium vittatum Eigenmann, Reports Princeton Univ. Exped. Patagonia, III,
1910, p. 400.

Habitat. — Marcapata Valley, eastern Peru.
Known from the types, 78 mm. long, in the British Museum.
Head 6.25; D. 6 (branched); A. 4 (branched); head as broad as long; diameter
of eye 2.33 times in the interocular width, which is 3.5 in the length of the head.
Snout slightly shorter than the postorbital part of head. Barbels equal to eight-
tenths the length of head. Dorsal originating in advance of the anal opening, the
the distance from its point of origin to the caudal one and one-half times in the
distance from the former to the tip of the snout. Anal originating slightly behind
the vertical from the last dorsal raj", the distance from the base of its last ray to
the caudal four and one-half times in the total length. Longest branched ray of
pectoral three-fourths the length of the simple outer ray, which is as long as the
head. Ventrals extending six-tenths of the distance from their base to the origin
of the anal. Caudal truncate. Head and body with dark spots; a dark longi-
tudinal stripe along the middle of the side.

14. Pygidium dispar Tschudi. (Plate XLV, fig. 5.)
Pygidium dispar Tschudi {partim), Faun. Peruana, IchthyoL, 1845, p. 22, pi. 3,
upper figure. (Eastern slope of the Peruvian Andes at an altitude of 14,000
ft.); Eigenmann & Eigenmann, Proc. Cal. Acad. Sci. (2), II, 1889, p. 52
(Callao); Occasional Papers Cal. Acad. Sci., I, 1890, p. 335 (Callao); Proc.
U. S. Nat. Mus., XIV, 1891, p. 36; Pellegrin, Bull. Soc. Zool., Paris,
XXIX, 1904, p. 91; Starks, Proc. U. S. Nat. Mus., XXX, 1906, p. 770 (Eteri,
Peru); Poissons des Lacs des Haut Plateaux dc I'Amer. Sud, 1907, p. 17 (Lake
Titicaca); Eigenmann, Reports Princeton LTniv. Exped. Patagonia, III, 1910,
p. 400.

Habitat. — High Andes of eastern and western Peru, down to Callao and Eteri.

The P. dispar recorded by Ribciro from the Rio Iporanga of southeastern

Brazil is a different species. Tschudi saj's the species is abundant in the highland

300 MEMOIRS OF THE CARNEGIE MUSEUM.

between the two chains of the Cordilleras, but on the eastern slope only. It is
(luite possible that Tschudi had two species and that the unspotted male he figured
is the taczanowskn of Steindachner. The specimens recorded by Pellegrin arc
im)]ia1)ly /-'. rimdatum.

Head 5.2; D. 12; A. 9. Elongate, compressed, the depth everywhere less than
the length of the head. Head longer than wide by more than a diameter of the eye.
Eye moderate, four times in the interocular, equidistant from tip of snout and end of
opercle. None of the barbels reaching (juite to tlie gill-opening. Ciill-openings
continued forward to l>eIow the eye. Pectorals oliliquely rounded, the first ray
produced in a filament. Origin of dorsal equidistant from tip of caudal and anterior
margin of the eye, the whole fin in front of the anal and behind the ventral fins.
Caudal emarginate. Distance of anal from base of caudal six times in the length.
Origin of ventrals midway between tip of snout and tip of caudal.

Reddish brown; sides, back, dorsal and caudal fins with large dark spots,
those on the head sniall(>st; lower surface plain.

1."). Pygidium punctulatum (Cuvier & Valenciennes). (Plate XLV, fig. 4.)
Trichomycterus jnmctulalus Cuvier & \'alenciennes. Hist. Nat. Poiss., XVHI,

1846, p. 488 (Lima); Liitken, \'elhas Flodens Fiske, 1875, p. 137 (Callao).
Pyqidium dispar punctulatum Eigenmann & Eigenmann, Proc. Cal. Acad. Sci.

(2), II, 1S80, p. 52 (Rio Reniac, near Lima); Occasional Papers Cal. Acad.

Sci., I, 1890, p. 33G (Rio Remac, largest ISO mm.); Proc. U. S. Nat. Mus.,

XIV, 1890, p. 36.
Pygidium punctulatum Starks, Proc. U. S. Nat. Mus., XXX, 190G, p. 771" (Callao);

Eigenmann, Reports Princeton Univ. Exped. Patagonia, III, 1910, p. 400.
Trichomycterus punctatus Cuvier & Valenciennes, /. c, p\. 552.

Habitat. — Rio Remac, Peru.
4234, I. U. M., one, 145 mm., a female with empty ovary. Callao.

From the Harvard collections.

Head 5.33-5.66; D. 12; A. 10.

Teeth conic, in about five series in the middle of the jaws.

Origin of dorsal equidistant from tij) of caudal and somewhere between occiput
and anterior margin of eye; distance of anal from base of caudal 6-6.5 in the length.

16. Pygidium taczanowskii (Steindachner). (Plate XLVI, figs. 5-8.)
f Pygidium disjxir T.schi'di (in part). Fauna Peruana Ichthyol., ]"». 22, pi. 3 (lower

figure) .
TrichomyctcruH taczanowskii Steindachner, Flussf. Siidam., IV, 1882, p. 22, pi.

IV, figs. 1-16 (Rio de Huambo; Rio de Tortora).

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 301

Pygidium taczanowsHii Eigenmann & Eigenmann, Proc. Cal. Acad. 8ci. (2),

II, 1889, p. 52; Occasional Papers Cal. Acad. Sci., I, 1890, p. 338; Proc. U. S.
Nat. Mus., XIV, p. 37; Eigenmann, Reports Princeton Univ. Exped. Patagonia,

III, 1910, p. 400.

Habitat. — North and central Peru, between the Andes.

Head in specimens 110-113 mm. 5-5.5; in a specimen 390 mm. 4.75; D. 9-10;
A. 7; P. 9; width of head 1.2 in its length, snout 2-2.33; interorbital 3-3.33, nasal
barbels 1-1.25 in the head, in small specimens, 1.4 in larger specimens, maxillary
barbels 1.21-1.25, lower barbels 1.6-2; width of mouth two times in the length of
the head ; anterior margin of eye slightly in front of the middle of the head in smaller
individuals, in the middle in the larger; teeth brush-like; opercular and interopcr-
cular spines numerous, in several series, mostly concealed; origin of dorsal variable,
moving back with age, in a specimen 110 mm. its origin much nearer gill-opening
than to caudal; in specimens 390 mm. 1.22 nearer middle caudal rays than tip of
opercle; origin of ventrals in "specimens up to 210 mm. almost directly under the
origin of the dorsal, in a specimen 390 mm. half the length of the head farther
forward; the origin of the anal in front of the end of the dorsal in small specimens,
under it in the specimen 390 mm. long; first jiectoral ray jM-olonged, its length 1-1.37
in the length of the head. Without spots, bands, or stripes.

17. Pygidium rivulatum (Cuvier & Valenciennes). (Plate XLV, figs. 2, 3.)

Trichomycterus rivulatus Cuvier & Valenciennes, Hist. Nat. Poiss., XVIII,
1846, p. 495 (Guasacona); GtJNTHER, Cat. Fishes Brit. IMus., V, 1864; Cope,
Proc. Amer. Philos. Soc, XVII, 1877, p. 46 (Lake Titicaca); Pellegrin,
Bull. Soc. Zool. Paris, XXIX, 1904, p. 91; Poissons dcs Lacs des Hants
Plateaux, de I'Am. Sud., 1907, p. 17 (Rio de Pazna, lac Poopo).

Pygidium rivulatum Eigenmann & Eigenmann, Proc. Cal. Acad. Sci. (2), II, 1889,
p. 51 (Cuzco; Moho and Puno, Lake Titicaca); Occasional Pajiers Cal. Acad.
Sci., I, 1890, p. 330, Proc. U. S. N. Mus., XIV, 1891, p. 36; Starks, Proc. U. S.
N. Mus., XXX, 1907, p. 771 (Lake Titicaca); Eigenmann, Reports Princeton
Univ. Exped. Patagonia, III, 1910, p. 399.

? Trichomycterus incw Cuvier & Valenciennes, /. c, 490 (Rio Guatanai at Cuzco).

Trichomycterus gracilis Cuvier & Valenciennes, I. c, 497 (Rio Azangaro near
Guasacona; Rio Guatanai near Cuzco; Rio Pontezualo near Coroico; Lake
Compucila near Cuzco); Cope, Proc. Amor. Philos. Soc. XVIT, 681, 1S77
(Tinta).

Trichomycterus barhatida Cuvier & \'alenciennes, /. c, 498 (Guasacona; Rio
Pontezualo near Coj-oico).

302 AfEMOIRS OF THE CARNEGIE MUSEUM.

Trichomycterus pentlandi Castelnau, Anim. Nouv. Am. Sud.,49, pi. XXIV, fig. 1,

1855 (Lake communicating with the Ucayale).
Trichomycterus pictus Castelnau, Anim. Nouv. Am. Sud., 59, pi. XXIV, fig. 2.

1855 (Lake Titicaca).
Trichomycterus dispar Gunther (partim), Cat. Fishes Brit. Mus., V, 273, 1864
(Lake Titicaca; Rio de Pontezualo; Andes de la Paz; Guasacona; Rio de Azan-
garo); Garman, Bull. Mus. Comp. Zool. Ill, 275, 1875 (Lake Titicaca).
?Pellegrin, Bull. Soc. Zool. Paris, XXIX, 1904, p. 91; Poissons des Lacs des
Hauts Plateaux de I'Am. des Sud., 1907, p. 7 (Lake Titicaca).
Trichomycterus pardus Cope, Proc. Acad. Nat. Sci., Phila., 1874, p. 132.

Habital. — High Andes of Peru, about Cuzco, Titicaca, Jequetepeque, etc.
13833, I. U. M., one, 93 mm. Tirapata, eastern Peru. 13000 ft. From Rosen-
berg.
13750, I. U. I\I., one, 145 mm. Ollantaytambo. E. Heller.

Teeth in about five series in the middle of the jaws, those of the outer series
narrow incisors, those of the innermost row conic.

Head 4.5-5.5; depth 3.75-6.5; D. 13; A. 11. Tail compressed, head depressed,
about as wide as long; eye equidistant from tip of snout and end of opercle. Nasal
barbels reaching to the posterior margin of the eye, longer in the young. Upper
maxillary barbel about to edge of pre-opercle. Mouth wide, more than. one-third
the length of tlii^ head. Pectoral rounded, the first ray prolonged in a short fila-
ment, except in the very young. Origin of dorsal equidistant from tip of caudal
and a point between occiput and posterior nares, its posterior portion always over
the anterior half of the anal. Accessory rays of the caudal very numerous, their
division from the true caudal rays marked. Caudal always rounded, its distance
from the anal 4.5-4.4 in the length. Color of largest specimens dark reddish brown,
sides with fine white or silvery spots and vermiculations. Specimens from 100-
200 mm. greatly variable, grayish or dark brown, with darker markings; sometimes
the ground color predominating, sometimes only forming reticulations between the
dark markings; young with an interrupted dark band along the sides.

18. Pygidium poeyanum (Cope).

Trichomycterus livulatus Cope {non Cuvier & Valenciennes), Proc. Acad. Nat. Sci.

Phila., 1874, p. 132 (Arequipa).
Trichomycterus poeyanus Cope, Proc. Am. Philos. Soc, 1877, p. 47.
Pygidium poeyanum Eigenmann & Eigenmann, Proc. Cal. Acad. Sci. (2), II, 1889,

p. 50; Occasional Papers Cal. Acad. Sci., I, 1890, p. 326; Proc. U. S. Nat. Mus.,

EIGENMANN: the PYGIDimyE, A FAMILY OF SOUTH AMERICAN CATFISHES. 303

XIV 1891 p 36; Eigenmann, Reports Princeton Univ. Exped. Patagonia,
III, 1910, p. 399; Fowler, Proc. Acad. Nat. Sci. Phila., 1915, p. 229 (note on

type).

^abita^— Arequipa. , ., , r^ i

This species named by Cope without any sort of description is said by Fowlor
to be " close to rivulatum, differing in its large dark blotches."

19. Pygidium barbouri Eigenmann.
Pygidium barbouri Eigenmann, Reports Princeton Univ. Exped. Patagonia, III,

1910, p. 400; Ann. Carnegie Mus., VII, 1911, p. 214, pi. XXXII.

Habitat.— Beni River, eastern Bolivia.
12566 I U M , 37 mm. and 2465a-6, C. M., two, cotypes. Rio Bern, tropical

eastern BoUvia. Obtained by Mr. Thomas Barbour at La Paz, Bohvia, from

the Beni River.

This species has conical teeth.

Fig. 9. Pygidium barbouri Eigenmann. Mtcr Eigenmann, Annals Carnegie Museum. VII,
pi. XXXII.

Head 4.66; depth 7; D. 8; A. 6; eye 3 in snout, 7 in head, 2.5 in space between
the eyes. Width of head equals its length behind the posterior nares, the body
tapering to the caudal; nasal barbels reaching to posterior margin of the eye, the
longer maxillary barbel scarcely to the gill-opening when laid straight back. Teeth
minute, in bands. First pectoral ray prolonged, not as long as the head; dorsal
subtruncate, none of its rays prolonged; distance of origin of dorsal from caudal 2.6
in the length; origin of anal from base of middle caudal rays 3.75 m the length;
caudal cmarginate; accessory rays not evident; ventrals not reaching the short,
scarcely rounded anal. A dark median band from the gill-opening to the tip of the
middle caudal rays, a light stripe above it; the back chocolate.

20. Pygidium fassli Steindachner.
Pygidium fassli Steindachner, Anz. K. Akad. Wiss. Wien, 1915, No. XVII, p. 200
(Rio Songo, Province North Yungas, Bolivia).

304 MEMOIRS UF THE CARNEGIE MUSEUM.

Head 8.77; depth 6; D. 9; A. 7; P. 9; teeth pointed, m several irregular series;
head a little longer than broad; eye in middle of head; nasal barbels reaching about
to lateral end of head, maxillary barbels a little beyond origin of pectoral. First
))ectoral ray moderately elongate; caudal truncate; origin of anal behind the vertical
from the middle of tl»e dorsal, half a head nearer to ba.se of middle caudal rays than
to the lateral margin of the head; snout rounded. Body velvety with minute
tubercles. Upper part of head, back, and sides light chocolate with darker spots in
tolerably regular rows; a dark lateral band, the spots above it larger than the others,
those of the uppermost rows sometimes confluent. Fins unspotted.

21. Pygidium oroyae Eigenmann & Eigenmann.

I'ygidiuHi uroijiv EiciENMANN & Eigenmann, Proc. Cal. Acad. Sci. (2), II, 1889,
p. 51; Occasional Papers Cal. Acad. 8ci., I, 1890, p. 334 (Pochachara, Oroyo
River); Proc. U. S. Nat. Mus., XIV, 1891, ]). 36; Eigenmann, Reports Prince-
ton Univ. Exped. Patagonia, 111, 1910, p. 399; Evermann & Radcliffe,
Bull. 95, U. S. Nat. Mus., 1917, p. 35, pi. IV, fig. 2 (Oroyo).
Habitat. — Rios Oroj'O and Perene, central Peru.

5792, C. M., eighteen, 24-90 mm. Spring supplying water to Tarma, Peru.
Lola Vance.

Fni. 10. Pygidium oroya; Eigenmann & Eigeninanii. After Kvciiiiann it Radcliffe.

Head 5.75-6; depth 5.75-8; D. 12; A. 10-11; P. 10. Head about as long as
wide; none of the barbels reaching the gill-opening; teeth all pointed; gill-membrane
narrowly joined to the isthmus, with a narrow, free margin. Pectoral shorter than
head, fan-shaped, the first ray not prolonged. Dorsal inserted over or sHghtly
behind the vent, its last ray ov(>r or behind the middk; of the anal, its origin equi-
distant from anterior margin of eye or occiput and tip of caudal, its distance from
the base of the caudal 1.5 in its distance from the snout. Caudal broadly rounded,
its distance from the anal 4-4.75 in the length. Ventrals extending to or beyond
the anus, their origin alwut midway between tip of snout and tip of caudal or nearer
the former. Chocolate brown; sides, back and unpaired fins with irregular groujjs
of dark points; traces of a dark lateral line in the young.

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 305

22. Pygidium quechuorum Stoindachner.
Pygidium quechuorum Steindachner, Anz. Ak. Wiss. Wien, 1900, p. 207 (Arequipa)
Denksch. Ak. Wiss. Wicn, LXXII, 1902, p. 137 (49 of separate), pi. IV, fig.
3-3a (Rio Chile, Arequipa); Eigenmann, Reports Princeton Univ. Expcd.
Patagonia, III, 1910, p. 400.
Habitat. — Rio Chile at Arequipa, Peru.

Fig. 11. Pygidium quechuorum '6i<iuida,chimv. .\ftcr Steindachner.

Known from the types, five specimens, 51-64 mm. long, in the Vienna Mu.seum.

Head about 5; depth 5.66-5.75 in total length; eyes very minute; intcrorbital 3
in the head, snout 3; width of head equals length of head or only very little less;
first pectoral ray not prolonged, the fin 1.5 in the head; maxillary barbel to some
part of the interorbital spines; origin of ventrals almost exactly in the middle;
origin of dorsal about equidistant from base of caudal and pectoral; origin of anal
behind the dorsal ; caudal rounded or subtruncate ; upper parts marbled ; a narrow,
diffuse lateral band, which is sometimes faintly interrupted.

Key to the Species of Pygidium from Venezuela, Colombia, Panama, and Ecuadou.
a. Teeth incisors, apparently conic in the very young;.

h. Last dorsal ray over the last anal ray; distance between last anal ray and base of niiildle uaiulal
ray about 2.28 in its distance from the snout; distance between last anal ray and base of middle
caudal rays five and one-half in the length; obscure spots about as large as the eye evenlj' dis-
tributed over back and siile.->, no lateral band 23. laticeps (Kner)

.66. Last dorsal ray over the anal.

c. Sides with a lateral band or nearly CDufluent series of sjiots.

d. Maxillary barbel extending beyond base of last pectoral ray; origin of ventrals equidis-
tant between caudal and some part of the opercular spines; ilistance between anal
and caudal four and one-half to four and three-fourths in the length; distance between
origin of dorsal and i)ase of caudal ai)out two in its distance from the snout; a narrow

lateral band, a variable number of small spots 24. steilatum I'^igenmann.

dd. Ma.xillary barbel extending little beyond origin of the pectoral or shorter; a dark baud or
series of spots below and another above the median band.
e. Origin of ventrals equidistant from caudal and middle of pectoral; distance between
anal and caudal five in the length; distance between origin of dorsal and caudal
a little more than two in its distance from the snout .... 2."). chapmani Eigenmann.
ec. Origin of ventrals nearer head than caudal; distance between anal and caudal five
to five and one-half in the length; distance between origin of do/sal and caudal
one and four- fifths to two in its distance from the snout. .20. tsnium (Kner).

306 MEMOIRS OF THE CARNEGIE MUSEUM.

cc. Sides with numerous spots, those along the middle line not forming a band; origin of ven-
trals equidistant from caudal and base or middle of the pectorals; distance between the ■
anal and caudal four and three-tenths to five in the length; distance between origin of the
dorsal and the caudal one and three-fourths to one and four-fiftlis in its distance from

the snout 27. caliense Eigenmann.

ccc. Sides plain; maxillary barbel extending beyond the axil; origin of ventrals equidistant from
caudal and pre-opercle; distance between anal and caudal five and one-half in the length;
distance between origin of dorsal and caudal two in its distance from the snout; origin of
anal a little in advance of the middle of the dorsal. See also kneri.

28. latidens Eigenmann.
aa. Teeth sharp-pointed, conical or recurved conical.^'

/. Origin of ventrals nearer to caudal than to tip of pectoral filament, the distance between the ven-
trals and caudal two in the distance from the snout; distance between origin of dorsal and
caudal two and two-fifths in its distance from the snout. Sides densely covered with small

spots with only vermiculating light lines between them 29. metae Eigenmann.

//. Origin of ventrals nearer to tip of jiectoral filament than to caudal, usually much further forward.
g. Sides plain.

h. Origin of dorsal nearly over origin of the ventrals, nearer the eye than the tip of the
caudal; distance between origin of dorsal and caudal 1..5 or less in its distance from

the snout, head 4.5-5.33 in the length 30. stramineum Eigenmann.

hh. Origin of dorsal above or a little in advance of the vent, its distance from the caudal
1.8 in its distance from the snout; head six times in the length; caudal subtruncate;

barbels as long as head 31. unicolor Regan.

hhh. As under h, caudal emarginate, barbels reaching considerably beyond origin of pec-
toral 32. kneri (Steindachner).

hhhh. Origin of dorsal distinctly behind the origin of the ventrals, much nearer the tip of the

caudal than the eye striatum. No. 41, which see.

g(j. Sides irregularly spotted, more rarely a lateral band, the spots along the middle of the sides
rarely in a distinct series; caudal rounded.
i. Maxillary barbels very slender, reaching to the middle of the pectoral rays; eye entirely
in the anterior half of the head; origin of dorsal eciuidistant from tip of caudal and

opercle; sides and back with moderate-sized dark spots 33. meridae Regan.

ii. Maxillary barbels not reaching to the middle of the pectoral; eye in middle of the head.

j. Origin of dorsal, on an average, slightly nearer to the caudal than to the eye; dorsal

inclusive of the rudimentary rays most frequently 12.5; head a little longer than

wide; distance between dorsal and caudal 1..5-1.7 in its distance from the snout;

sides and back with Numerous large spots, rarely in rows, the spots largest in the

larger specimens 34. bogotense Eigenmann.

jj. Origin of dorsal nearly equidistant from tip of caudal and snout; D. 11.5 or 12.5;
head as wide as long; distance between dorsal and caudal 1.4-1.52 in its distance
from the snout; sides and back in the largest with numerous irregularly arranged
spots about the size of the eye, the spots larger and less numerous in the young.
Sometimes nearly plain, sometimes with a lateral stripe.

35. nigromaculatum (Boulenger).
ggg. Sides with distinct longitudinal bands or rows of spots; caudal emarginate, truncate, or
truncate-rounded.
" Not examined in unicolor, kneri, and retropinne.

EIGENMANN: the PYGIDIID.E, a family of south AMERICAN CATFISHES. 307

k. Caudal oiiuirgiiiatc; origin of dorsal ciiuidistant from tip of caudal and opcrcle or pre-

operclc, its distance from the caudal 1.5-l.S in its distance from the snout; head five in

the length; sides and back with numerous dark spots, those along tlie middle of the

sides forming a distinct row, sometimes confluent along the anterior half of the bodj'.

36. banneaui Kigenmann.
kk. Caudal truncate or rounded.

I. Dorsal, anal, antl caudal truncate; origin of dorsal equidistant from tip of caudal and
pre-operele, its distance from the base of the middle caudal rays 1.0 in its distance
from the snout; sides with a faint l)road band, oversown like the i)ack with spots

about the size of the eye 37. spilosoma Regan.

II. Dorsal and anal rounded.

m. Lateral band above the middle; ma.xillary barbels extending to the a.\il.

71. Cauilal truncate-rounded; origin of dorsal equiilistant from tip of caudal
and eye or nasal barbel, its distance from the caudal about 1.4 in its dis-
tance from the snout; the lateral band or row of spots above the middle,
from the upper part of the gill-opening to above the middle of the caudal.

38. dorsostriatum Eigenmann.

nil. Barbels very short, about reaching the eye; origin of dorsal equidistant

from tip of caudal and opercle, a faint lateral band, sides reticulated,

first pectoral ray not prolonged 39. venulosum Steindacliner.

mm. Lateral l)aud, if present, in the middle of the sides.

o. Origin of dorsal equidistant from tip of caudal and nasal barbel, its
distance from the base of the middle caudal raj's about 1.4 in its
distance from the snout; a lateral band increasing in width to the
caudal; middorsal area dark, a dark stripe between the lateral stripe
and the dorsal stripe in front of the dorsal.

40. iatistriatum Kigenmann.
uo. Origin of tlorsal equidistant from tip of caudal and a point between the
midiUc of the pectoral and the pre-opercle, its distance from the
middle caudal rays 1.8-2 in its distance from the snout.
p. Maxillary barbel reacliing a little beyond the axil or shorter; color
very variable, ])Iain, or with one to three lateral stripes; origin of
the dorsal typically ecpiidistant from tip of caudal and midille of

pectoral rays 41. striatum Meek & Hildebrand.

Pl>. Maxillary barbel reaching to near the end of the lower pectoral ray,
longer tluiu tlie head; origin of dorsal equidistant from tip of caudal

and opercular spines 42. regani Kigenmann.

ouu. Distance between origin of dor-sal and caudal 2.2-2.4 in its distance from
the snout; head as broad as long; eye in the middle of the head; distance
between base of last anal ray and the caudal 5.4 in the length. An
indistinct darker stripe along the middle of the side and traces of some
darker spots 43. retropinne (Regan).

23. Pygidium laticeps (Knor).
Triclioinijdcru^ laticeps Knek, Sb. Aciul. Wis.s. Miinclu'ii, 1SG3, p. 228; Kner &
STEiNDACHNER,Abhaiidl. K. Bayer. Akad. Wiss., II. CI., Vol. X, Part I, 1864,

308 MEMOIRS OF THE CARNEGIE MUSEUM.

p. 54 (western slope of Andes of Ecuador); Gunther, Cat. Fishes Brit. Mus.,
V, 18G4, p. 274.
Pyyidium laticeps Eigenm.^nn & Eigenmann, Proc. Cal. Acad. Sci., II, 1889, p. 51;
Occa.sional Papers Cal. Acad. Sci., I, 1890. p. 334; Proc. U. S. Nat. Mus., XIV,
1891, p. 36; EiGENMANN, Reports Princeton Univ. Exped. Patagonia, III,
1910, p. 399.
Habitat. — ^Western slope of the Andes of Ecuador.

13811, I. U. M., one, 79 mm. Below Paramba, Prov. Imbabura, Ecuador. 2600
feet. Henn.

13812, I. U. M., 7094a-rf, C. M., seventy-one, largest 89 mm. Mindo. Henn.
Head 5-5.2; D. 10.5; A. 8.5; P. 7.

G. 12. Pi/gidiuiii laticeps (Kner & Stelndacluier). After Kiier & Steiudachner.

The barbels in the specimens average a little longer than in the specimens of
P. tcenium from Llanos. Distance between last anal ray and base of middle caudal
ray about 5.5 in the length; distance between origin of dorsal and base of middle
caudal rays on an average 2.28 in its distance from the snout; the last dorsal ray over
the last anal ray, the two fins coterminous.

Teeth: Incisors in two series in each jaw.

Dark brown, with obscure spots, about the size of the eye, evenly distributed
over the sides and back. No trace of a lateral band in any of the specimens. •

In the very small the last anal ray is a little back of the vertical from the last
dorsal ray, and the color is uniform.

24. Pygidium stellatum Eigenmann. (Plate XLVII, fig. 1.)

7097, C. M., type, 78 mm. Quebrada Sarjento. Gonzales.

7098a-c, C. M.; 13814, I. U. M., paratypes, 65-85 mm. Quebrada Sarjento.
Gonzales.

7096O-C, C. M.; 13815,1. U. M.,five, 45-86 mm. Quebrada Guamal. Gonzales.

7099f;-b, C. M.; 13816, I. U. M., five, 37-55 mm. Quebrada Guadual. Gonzales.

7100O-I, C. M.; 13817, I. U. M., seventeen, largest 50 mm. Rio Guaduas. Gon-
zales.

13807, I. U. M., three, 31-50 mm. (Quebrada Cristalina, 28 kilom. above Puerto
Berrio, 1000 ft. E. B. Wimam.son.
Head 5.5-6; D. 10.5; A. 7.5; P. 7; eye in middle of the head, or very shghtly in

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 309

front of the middle; interocular three times in the head; teeth broad incisors, in two
series.

Nasal barbels extending to the tip of the opercular spines or a little further,
maxillary barbels usually beyond base of last pectoral rays; pectoral narrow, the
filament longer than the head; origin of ventrals equidistant from base of middle
caudal rays and some part of the opercular spines, the tips of the ventrals reaching
vent; origin of anal under anterior half of the dorsal, the distance between the base
of the last anal ray and the base of the middle caudal rays 4.5-5 in the length;
caudal rounded, 5 to 6.5 in the length; origin of dorsal about equidistant from tip
of caudal and opercle, its distance from the base of the middle caudal rays about two
times in its distance from the snout.

A narrow, dark lateral stripe, a variable number of dark spots, smaller than
the eye, above the band and below it on the tail.

The specimens from Cristalina have the lateral band very broad, the maxillary
barbels reaching to the middle of the pectoral.

25. Pygidium chapmani Eigenmann. (Plate XLVII, figs. 2, 3.)

Pygidium chapmani Eigenmann, Indiana University Studies, No. 16, dated Sept.,
issued Dec. 23, 1912, p. 18. (Boquia.)

4817, C. M., type, 106 mm.; paratypes, 4818a-2, C. M.; 12678, I. U. M., Boquia.
Eigenmann.

7091a-6, C. M.; 13805, I. U. M., 4, 78-118 mm. Rio Dagua at Caldas. Eigen-
mann

Habitat. — Upper Cauca Valley.
Head 5-5.75; D. 10.5; A. 7-8.5; P. 7; interocular 3.5 in the head; eye in middle

of the head; width of head equal to its length in the young, narrower in the adult.

Teeth in 75 mm. specimens long and very narrow chisels, in smaller specimens less

distinctly chisel-shaped, in 65 mm. specimens long and smaller, conical.

Nasal barbels extending to base or near tip of opercular spines; maxillary barbel

just beyond origin of pectorals.

Fig. 13. Pygidium chaymani Eigenmann. Type, 106 mm., C. M. No. 4817. Boquia.

310 MEMOIKS OF THE CAKNEGIE MUSEUM.

Pectoral narrow, the outer ray about equal to the head in length; origin of the
ventrals about eciuidi.stant from base of caudal and middle of i)ectorals, the tips
at or slightly beyond anus; origin of anal below middle or posterior part of the
dorsal, the distance between the base of its last ray and the middle caudal rays
five and one-third in the length; caudal distinctly rounded, about six and one-half
in the length; origin of dorsal over tip or middle of the ventrals, its distance from
the base of the middle caudal rays about two in its distance from the snout.

Smallest specimens with a black lateral band, a series of spots above and below

it in the older, the band breaking up into a series of spots in specimens over sixty

millimeters long. Th(> oldest specimens dark with ol^scure darker spots and mot-

tlings.

26. Pygidium tsenium (Kner).

Trichomycterus toenia Kner, Sb. Akad. Wiss. Miinchen, 1863, p. 228; Kner &
Steindachnek, Abhandl. k. Bayer. Akad. Wiss., II. CI., vol. X, part I, 1864,
p. 52 (western slope of Andes of Ecuador); GIjnther, Cat. Fishes Brit. Mus.,
V, 1864, p. 274.

Pygidium toenia Eigenmann & Eigenmann, Proc. Cal. Acad. Sci. (2), II, 1889,
p. 51; Occasional Papers Cal. Acad. Sci., I, 1890, p. 334; Proc. U. S. Nat.
Mus., XIV, 1891, ]). 36; Eigenmann, Reports Princeton Univ. Exped. Pata-
gonia, III, 1910, p. 399.
Habitat. — Western slop(> of the Andes of Ecuador and southern Colombia.

13813 I. U. M., 7095rt-d, C. M., forty-two, 31 111 mm. Los Llanos, southern
Colombia. INIarch 8, 1913. Arthur Henn. .

Fui. 14. Pi/gidiiim Urnitim (Kner). After Kner & Steindachner.

Head 5.2-5.6; D. 9.5 or 10.5; A. 8.5; P. 7; eye in the middle of the head, inter-
orbital three in the length of the head.

Nasal barbel reaching to the opercular spines, the maxillary barbels to the
pectoral; outer pectoral ray with its filament a little shorter than the head, the rays
about equal to the head without the snout ; ventrals reaching the vent, their origin
equidistant between base of middle caudal rays and opercular spines; origin of
anal under anterior half of the dorsal, the distance between the base of its last ray
and the middle caudal rays about five in the length ; caudal rounded, five and five-

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 311

tenths to six and fivo-tonths in the length; origin of dorsal over tips of ventrals, its
distance from the base of the middle caudal rays one and eight-tenths to two in its
distance from the snout.

Teeth in the largest specimen narrow chisels, three rows in the premaxillary and
the middle of the mandible. In the young the teeth are more nearly conical.

Color variable ; a dark band from the opercle to the middle caudal rays, some-
times in ])art, or as a whole, replaced by a series of large spots; an irregular series
of irregular spots half way between the lateral band and the ventrals and anal, this
series more rarely replaced by a band ; a band or a series of spots between the lateral
band and the mid-dorsal line ; a mid-dorsal band ; small spots sometimes intersjiersed
among the larger ones.

27. Pygidium caliense Eigenmann.-'-
Pygklium caliense Eigenmann, Indiana University Studies, No. 16, p. 18, dated

Sept., 1912, issued Dec, 1912.
4819, C. M., type, 53 mm. Cali. C. H. Eigenmann.

Head 4.88-5.75; D. 10.5 or 11.5; A. 9.5 or 10.5; P. 7; eye about in middle of
the head interocular 3.5-4 in the length of the head.

Fig. 15. Pygidium caliense Eigenmann. Type, 4S10, Caiii. Miis., .">.'5 mm. Cali.

Nasal barbels extending to base or end of opercular spines, very little shorter
in the type ; maxillary barbel extending to the end of the opercular spines or beyond
the origin of the pectorals; pectoral rays about equal to the length of the eye and
the post-orbital part of the head, the filament extending for more than half the
length of the fin beyond the tip of the divided rays on one side in the largest speci-
men, nearly as long as the head, shorter in other specimens; origin of the ventrals
equidistant from base of middle caudal rays and base or middle of the pectoral
rays, reaching just beyond the vent; origin of the anal about under the middle of
the dorsal, the distance between the base of its last ray and the base of the middle
caudal ray four and one-third to five in the length; caudal rounded, five and one-
half to six and one-half in the length ; accessory rays large, numerous; origin of dorsal

-■- Tiie head in the figure is a little too .short.

312 MEMOIRS OF THE CARNEGIE MUSEUM.

over middle of the ventrals, its distance from tlie middle of the caudal one and
three-fourths to one and eight-tenths in its distance from the snout.

Sides and back in the young with black spots, the middle ones of the sides
larger and forming a more or less regular series in the young and half-grown; in the
largest sjiecimen the caudal peduncle and base of the caudal are profusely covered
with spots smaller than the eye, the spots larger, less numerous and less conspicuous
forwards.

Teeth round-tipped incisors in the largest, more jiointed but distinct incisors
in the middle-sized specimens; the teeth of the t\']:)e narrow, pointed incisors.

28. Pygidium latidens Eigenmann. (Plate XLVII, fig. 4.)
Pygidium latidens Eigenmann, Proc. Am. Philos. Soc, LVI, Jan., 1918, p. G93.
13801, I. U. M., one, 53 mm. Small creek near the mouth of Rio Calima, north of

Buenaventura. May 7, 1913. Henn.

Head 5.5; D. 9.5; A. 7.5; P. 7; posterior edge of eye in advance of the middle of
the head; interocular 3.5 in the head.

Nasal barbel extending beyond the tips of the opercular spines; maxillary
barbel extending beyond the axil, longer than the head; pectorals broad, as long
as head without snout; pectoral filament equal to the distance from the snout to the
axil; ventrals not nearly reaching anus, their origin equidistant from the base of
the middle caudal rays and the interopercle; origin of anal about under middle of
the dorsal, distance between base of the last ray and the middle caudal rays five
and a half in the length; caudal rounded, about six in the length; accessory rays
well developed ; origin of dorsal over anus, its distance from the middle caudal rays
two in its distance from the snout; gill-membrane free to below the anterior spine
of the interopercle, without a free membrane across isthmus; both jaws with two
series of thin, chisel-shaped teeth.

Color plain, without spots or stripes.

29. Pygidium metae Eigenmann. (Plate XLVII, fig. 5.)
Pygidium 7netce Eigenmann, Proc. Am. Philos. Soc, LVI, Jan., 1918, p. 694.
13770, I. U. M., one, 78 mm. Barrigona. March, 1914. Manuel Gonzales.

Head 6.3 in the length; D. 10.5; A. 9.5, counting the rudimentary rays; P. 6;
width of head nearly equal to its length; eye entirely in the anterior half of the
head, snout 2.75 in the head, interocular 3.5. Teeth conic.

Nasal barbels reaching to tip of opercular spines, maxillary barbel slightly
beyond origin of pectorals; pectorals small, equal to the postorbital portion of the
head, the first ray with its filament equal to the head, origin of ventrals much nearer

EIGENMANN: the PYGIDIID.E, a family of south AMERICAN CATFISHES. 313

base of middle caudal rays than to tip of pectorals, their tips reaching the anal;
origin of anal under fourth dorsal ray (second fully developed ray), the distance
between the base of its last ray and the base of the middle caudal rays six times in
the length; caudal rounded; origin of dorsal over tip of ventrals, its distance from
the base of the middle caudal rays two and two-fifths times in its distance from the
snout.

Sides and back densely covered with spots about the size of the eye.

30. Pygidium stramineum Eigcnmann. (Plate XLIX, fig. 1.)
■ Pygidium stramineum Eigenmann, Proc. Am. Philos. Soc, LVI, Jan., 1918, p. 694.
7101, C. M., type; 13818, I. U. M., paratype, 46 and 50 mm. Quebrada del

Mango, Santander. Gonzales.
7089a, C. M., paratype, 35 mm. Quebrada del Maradat (?) Santander. Gonzales.
7090a-c, C. M., 13804, I. U. M., paratypes, seven, largest 45 mm. Quebrada da

Densino, Santander. Gonzales.
7102a-/i, C. M.; 13819, I. U. M., fifteen, largest 60 mm. Quebrada Deocamante,

Santander. Gonzales.
7103a-&, C. M.; 13826, I. U. M., four, the largest 67 mm. Quebrada de Zuarta,

Santander. Gonzales.
7104, C. M., one, 41 mm. Quebrada de La Honda, Santander. Gonzales.

Head 4.5-5.33; D. 10.5; A. 8.5-9.5; P. 9; posterior margin of eye in the middle
of the head; interorbital three in the length of the head; teeth bristle-like, in about
three series.

Nasal barbels reaching base of opercular spines or bej^ond origin of pectorals,
maxillary barbels to tip of opercular spines or axil; pectoral filament about equal to
the length of the head, the rays equal to the length of the head without the snout;
origin of ventrals equidistant from the base of the middle caudal rays and a point
between the axil and a httle in front of the operclc (and the tips of the opercular
spines in the type), tips of the ventrals slightly behind the vent; origin of the anal
behind the vertical from the base of the last dorsal ray or under the posterior half
of the dorsal, the distance between the base of the last anal ray and the middle
caudal rays 4.5—5 in the length, accessory caudal rays very large and numerous;
caudal rounded, six and a half times in the length ; origin of dorsal over the origin
of the ventrals, or but slightly behind this point, always nearer the eye than the tip
of the caudal, sometimes equidistant from tip of snout aiul tip of caudal, its dis-
tance from the base of the middle caudal rays one and a half or less in its distance
from the snout.

Uniform straw-colored in alcohol.

314 MEMOIRS OF THE CARNEGIE MUSEUM.

31. Pygidium unicolor Regan.
Pyfjidium unicolor Regan, Ann. i^' Mag. Nat. Hist. (8), XII, Nov., 1913. (Con-

doto.)

Habitat. — San Juan basin.

The following is the original description of Regan:

" Depth of body 7 in length, length of head G. Head as broad as long. Diam-
(>ter of eye 12 in length of head or 3 in interoeular width; eyes well in advance of
middle of head, close behind nostrils. Barbels as long as head. Dorsal 8-9, with
5 or 6 branched rays, rounded; oiigin above or a little in advance of vent, I5 as far
from end of snout as from base of caudal. Anal 7, with 4 branched rays; origin
below last rays of dorsal. Pectoral filament i to as long as head, branched rays f
length of head. Pelvics covering vent. Caudal subtruncate. Coloration uni-
form.

"Two specimens, 80 and 85 nun. in total length, from the Condoto (Spurrcll)."

32. Pygidium kneri (Hteindachner). (Plate XLVI, figs. 1,2.)
Trichomycterus knerii Steindachner, Ichthyol. Beitr., XII, 1882, p. 21, pi. V,

figs. 1-la.

Habitat. — Canelos, Rio Bobonaza; Rio Zamora, eastern slope of Ecuador;
Rio Meta, eastern Colombia.
13907, I. U. M., one, 155 mm. Barrigona, Rio Meta. Gonzales.

Head 5.7; depth 6.3; D. 10; A. 10 including the rudimentary rays; eye 9 in the
head, interoeular 3, snout 2.3; eye in middle of the head.

Nasal barbel extending a httle beyond gill-opening, as long as the head; maxil-
lary barbel reaching to near tip of the shortest pectoral raj'^; first pectoral ray with
its filament a Utile longer than the head, the rays about equal to the part of the
head behind the nasal barbels; origin of ventrals equidistant from base of middle
caudal rays and the eye; origin of anal under last dorsal ray; caudal truncate when
half expanded, slightly rounded or emarginate when fully expanded or compressed,
its middle rays equal to the length of the head; dorsal rays coterminous when de-
pressed; distance of origin of dorsal from base of middle caudal rays 1.6 in its dis-
tance from the snout; depth of caudal peduncle about 1.5 in its length, which is
five in the length.

Slightly darker above, without spots or streaks.

Steindachner's description and figure give the following variation from the
above.

"Head 5.25-5.6G; depth 6.75-7.5; D. 9; A. 7; eye 5-6 in the head; snout 2.5;
interoeular 2.66-3.75; width of the head 1.33 1.4 in its length.

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 315

"Nasal barbels reaching to gill-opening, maxillarj- barbel considerablj' beyond
origin of pectoral; upper pectoral ray prolonged; origin of the dorsal behind that
of the ventrals, its last ray over or a little in advance of the first anal ray; caudal
slightly emarginatc in the figure, said to be "schwach convex" in the text. Choco-
late brown, thickly peppered with somewhat darker, very small, irregular spots or
points."

33. Pygidium meridae Regan. (Plate XLIX, fig. 2.)
Pygidhim meridcc Regan, Ann. & Mag. Nat. Hist. (7), XII, Dec, 1903, p. 624

(Merida and from Rio Albireggas above Merida, 3500 meters), Eigenmann,

Reports Princeton Univ. Exped. Patagonia, III, 1910, 399.

Habitat. — Cordillera of Merida, Venezuela.
13771, I. U. M., one, 99 mm. Merida. Purcha.sed from Rosenberg.

Head 6 [-7]; D. 10.5 [6-7 branched rays]; A. 9.5 [4 or 5 branched rays]; P. 8;
eye in front of the middle of the head; interocular contained three and one-third
in the length of the head [3], snout two and one half times.

Nasal barbel reaching a little beyond the eye; maxillary barbel \evy slender,
reaching about to middle of the pectorals, longer than the head [as long or nearly as
long as the head]; outer pectoral ray equals length of maxillary barbel, the pro-
jecting filament being half as long as the rest of the fin [one and one-third times as
long as head] ; origin of ventrals equidistant from base of middle caudal rays and
posterior portion of head, the ventrals reaching the vent; origin of anal- below
penultimate dorsal ray; distance between last anal ray and the middle caudal rays
four and three-fourths in the length [four and two-thirds to five times]; caudal
rounded [truncate], six and a half times in the length; origin of the dorsal on the
vertical from a point just in front of the vent, over tip of ventrals; distance between
origin of dorsal and base of middle caudal rays one and three-fourths times in its
distance from the snout [one and two-thirds to one and four-fifths].

No lateral band; traces of dark spots.

The characters found by Regan are given in brackets.

34. Pygidium bogotense Eigenmann. (Plate XLIX, figs. 3, 4.)
Pygidium. bogotense Eigenmann, Indiana University Studies, No. 16, p. 18, dated
Sei)t., issued Dec. 23, 1912. (Madrid; diapinero.)
Habitat. — Plains of Bogota and northward.
4820, C. M., type; 4821, C. M.; and 12679 I. U. M.,paratypes, two hundred thirty-
nine, largest 80 mm. Puente de Supa, beyond Chapinero, north of Bogota.
Eigenmann.

316 MEMOIRS OF THE CARNEGIE MUSEUM.

4834, C. M.; 12680, I. U. M., paratypes, six. Madrid, plains of Bogota. Eigen-

mann.
University of Michigan, 94 mm. Mountains, 4,000 ft., Guira River, Santa Marta.

July 18, 1913. A. S. Pcarse.
University of JNlichigan, 66 and 68 mm. Small stream, San Lorenzo, Santa Marta,

4,500 ft. July 8, 1913. A. S. Pearse.
7087a-c, C. IM., 13802, I. U. M., five, largest 52 mm. Rio Piedras, Santander.

Gonzales.
7457, C. M.; 13845, I. U. M., five, largest 55 mm. Quebrada da Charda. San-
tander.
7088, G. M., 13803, 1. U. M., twenty-six, largest 80 mm. (Label illegible^" Puchada?

de la Porguira? de Norte Zipa Quira? ") Gonzales.
13800, I. U. M., 85 mm. Mill-stream, (yincinnati (twenty miles from Santa

Marta), Golombia. Dec. 31, 1916, 4,500 feet. E. B. Williamson.

Head 5.25-6; D. 10.5 in two specimens, 11.5 in four, 12.5 in eight, 13.5 in two;
A. 10.5; P. 8; center of the eye very little in front of the middle of the head; inter-
ocular about three in the length of the head; head but little longer than wide; teeth
conical, in three or four irregular series.

Nasal barbel extending to tip or base of opercular spines; maxillary barbel
extending to the base of the opercular spines or beyond the base of the pectoral;
pectoral rays about as long as the head behind the nasal barbel, pectoral filament
about as long as the head ; origin of ventrals equidistant from base of middle caudal
rays and tip or base of the opercular spines, tips of ventrals extending to or very
slightly beyond the vent; origin of anal under one of the last three dorsal rays or
just behind the vertical from the last one; distance between the base of the last anal
ray and the middle of the caudal ray four and three-fifths to five in the length;
caudal rounded, six to seven in the length; accessory caudal rays numerous and
large ; origin of dorsal over origin or posterior half of the ventrals, equidistant from
tip of caudal and eye,^^ its distance from the base of the middle caudal rays one and
five-tenths to one and seven-tenths in its distance from the snout.

-' In this specimen the origin of the dorsal is over the origin of the ventrals. In the specimens from
the plains about Bogota examined in this regard, only one had the origin of the dorsal a little further
forward, a number had it equidistant between the tip of the caudal and a point some distance behind the
eye. In tlie specimens from the Santa Marta Mountains, the origin of the dorsal is a little further for-
ward. These specimens approach nigrumacidalum, to which they ought perhaps to be referred. It is
certain that the largest specimens referred to nigrumaculatum from Santa Marta belong to a species dif-
ferent from those found on the plains of Bogotd. It is possible that P. hogoteme is also found in Santander
and Santa Marta, but it is also possible that the halfgrown of P. bogotense are indistinguishable from the
half-grown of P. vigromaaihitum, nnrl that the specimens from Santander and Santa Marta are really the
latter species.

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 317

Sides and back with numerous irregular spots, larger in the larger specimens,
sometimes referable to distinct series. The spots arc smaller in the specimens from
Santander.

35. Pygidium nigromaculatum (Boulenger). (Plate XLIX, fig. 5.)
Trichomycterus nigromaculatus Boulenger, Ann. & Mag. Nat. Hist. (5), XIX,

1887, p. 349 (Andes of Colombia).
Pygidium nigromaculatum Eigenmann & Eigenmann, Proc. Cal. Acad. Sci. (2),

II, 1889, p. 52; Occasional Papers Cal. Acad. Sci., I, 1890, p. 336; Proc. U. S.

Nat. Mus., XIV, 1891, p. 37; Eigenmann, Reports Princeton Univ. Exped.

Patagonia, III, 1910, p. 400.

Habitat— Andes of Colombia, especially Sierra de Santa Marta and Santander.
No. ? , University of Michigan, two, 138 and 165 mm. Small stream, San

Lorenzo, Santa Marta Mountains (4,500 ft.). Sept. 9, 1912. M. A. Carriker.
No. ? , University of Michigan, two, 118 and 150 mm. Same place, Jan.

16, 1913. M. A. Carriker.
No. ? , University of Michigan, one, 73 mm. Same place, July 8, 1913.

A. S. Pearse.

No. ? , University of Michigan, eight,-* largest 55 mm. Same place, July

9, 1913. A. S. Pearse.

No. ? , one, 115 mm. Locality?

13837, I. U. M.; 7447o-6, C. M., four, largest 93 mm. Quebrada de la Raya,
Santander. Gonzales.

7448a-6, C. M., two, the larger 45 mm. Quebrada Capitanejo, Santander. Gon-
zales.

7449a-c, C. M.; 13838, I. U. M., six, largest 68 mm. Quebrada de Cobarachior,
Santander. Gonzales.

Description of the Species from San Lorenzo.

The characters given by Boulenger are in brackets.

Head 5.24-5.75 [6.5 in total]; D. 11.5 or 12.5; A. 9.5; P. 9; eye in middle of
the head; interocular 3 in the length of the head; width of head equal to its length
[longer than the distance between snout and a line connecting the tips of the two
bunches of opercular spines]; teeth conical [pointed, recurved].

Nasal barbels extending to the tips of the opercular spines or to the base of the

" These specimens are so distorted that it is difficult to refer them to their proper place. The
origin of the dorsal seems to be equidistant from the tip of the caudal and the front of the eye. There
are traces of longitudinal bands.

318 MEMOIRS OP THE CARNEGIE AIUSEUM.

last pectoral ray; maxillary barbels extending to the base of the last pectoral ray
or a little bej'ond; pectoral broad, rounded, the filament equal or nearly equal to
the length of the head ; origin of the ventrals very little nearer base of middle caudal
rays than eye, their tips reaching the vent or very little bej^ond it; origin of anal
under the penultimate dorsal ray [anal entirely behind the dorsal], the distance
between its last ray and the middle caudal ray four and one half to five in the length ;
caudal rounded, about six in the length; accessory caudal rays not conspicuous;
origin of dorsal over the anterior two-thirds of the ventrals; origin of dorsal nearly
equidistant from tip of snout and tip of caudal, its distance from the base of the
middle caudal rays on an average 1.4 in its distance from the tip of the snout.

Sides and back in the largest with numerous irregularly arranged spots about
the size of the eye, the spots larger and less numerous in the young, much as in
P. bngotense.

In the specimens from La Raya, Santander, the dorsal and ventrals are a Httle
farther back, the ventrals equidistant from base of middle caudal rays and tip of
opercular sjiines, the distance between the dorsal and the middle caudal rays 1.52
in its distance from the snout. The anal is entirely behind the dorsal. The origin
of the dorsal is equidistant from the ej'e and the tip of the caudal. Plain or but
faintly spotted.

Specimens from Capitanejo resemble those from La Raya.

Some of the specimens from Cobarachior seem to be t3q:)ical bogotense, while
others approach the specimens from La Raya and P. latistrialum from Pinchote.
/■•. boyoiense, typical of the plains of Bogota, grades into P. nigromaculatum of
Santa ]\Larta in Santander and Santa Marta.

36. Pygidium banneaui Eigenmann. (Plate XLVIII, fig. 1.)
Pygidmm banneaui Eigenmann, Indiana University Studies, No. 16, dated Sept.,
issued Dec. 23, 1912, p. 19.
Habitat. — Streams near Honda, Colombia.
4815, C. M., type; 4816a-^, C. M., 12677, I. U. M., paratypes, eighty-nine speci-
mens, the largest 44 mm. Bernal Creek, near Honda. Eigenmann.
7456a-6, C. M.; 13844, I. U. M., four, 3.5-41 mm. Guaduas? Gonzales.

These specimens might be considered the young of some of the other species if it
were not for the fact that one specimen, 34 mm. long, contains eggs over a milli-
meter in diameter, which must be nearly mature.

Head 5.33-5.5; depth 5.5-7; D. 10.5 or 11.5; A. 7.5 or 8.5; P. 8; eyes slightly
in advance of the middle of the head; interocular three and five-tenths in the length
of the head; teeth conical.

EIGENMANN: the PYGIDIIDvE, a family of south AMERICAN CATFISHES. 319

Nasal barbels reaching to the tips of the opercular spines, maxillary barbel to
near the middle of the pectoral; upper pectoral ray prolonged in a filament, as
long as the head or a little longer; ventrals reaching the vent, their origin about
equidistant from snout and tips of middle caudal rays; origin of the anal under the
middle of the dorsal, the distance between the last ray and the middle caudal rays
4.5-5 in the length; caudal distinctly emarginatc, about five in the length; origin
of dorsal a little nearer tip of caudal than eye, the distance between the origin of
the dorsal and the caudal 1.4-1.66 in its distance from the snout.

Specimens 18 mm. long have a black line from the nasal barbel to near the tip
of the middle caudal rays, accented in places; in specimens 20 mm. long the line is
accented more strongly, appearing to be breaking up into spots; there are also
spots on the back; in older specimens the line becomes diffuse; with growth a dis-
tinct series of spots develops along the middle of the back in front of the dorsal,
and another series between these and the lateral series; in the largest the sides and
back are profusely spotted, the spots varying in size and arrangement.

In the specimens from Guaduas the barbels are a little shorter and the dorsal a
trifle farther forward. The color markings are less profuse than in the type.

37. Pygidium spilosoma Regan. (Plate XLVIII, fig. 2.)
Pyyidium spilosoma Regan, Ann. & Mag. Nat. Hist. (8), XII, Nov., 1913, p. 468.

(Rio Sipi and Rio Tamana.)

This species from the Pacific drainage of central Colombia is known from tlu'ce
specimens 130-250 mm. long, described by Regan, and 7092, C M., 97 mm. Cor-
dova on the Rio Dagua. Eigenmann.

In the following description, Regan's data are given in brackets.

Head 6 [to 6.75]; depth 7 [to 8]; D. 11.5 [9, with 6 branched raysj; A. 9.5 [7,
with 4 branched rays] ; P. 8 ; eye very little in front of the middle of the head ; interocu-
lar 3.5 in the length of the head [2.5-3] ; head longer than wide, tapering forward, the
space between the nasal barbels 6.5 in the length of the head. Teeth minute, conical.

Nasal barbels extending to the base of the opercular spines, the maxillary barbel
to their tip [to basal part of pectoral] ; i)cctoral rather narrow, tlie upper part trun-
cate, the filament equal to the head; origin of the ventrals eciuidistant from base of
middle caudal rays and the tip of the oi)ercular spines, a little too far forward in the
figure, origin of the anal under the middle of the dorsal [a little behind end of dorsal],
the distance between the base of its last ray and the base of the middle caudal rays
5 in the length; caudal truncate, six and one-fourth in the length; dorsal obliquely
truncate, origin of dorsal over posterior half of the v(>ntrals, its distance from the
base of the middle caudal rays 1.6 in its distance from the snout.

320 AfEMOIRS OF THE CARNEGIE MUSEUM.

An obscure, diusky band along the middle of the sides; sides and back with
obscure spots about the size of the eye.

38. Pygidium dorsostriatum Eigenmann. (Plate XLVIII, fig. 3.)
Pijgidium dorsostriatum Eigenmann, Proc. Am. Philos. Soc, LVI, Jan., 1918, p.

695.
7093a-t, C. M.; 13810, I. U. .M., four, 18-7G mm., the largest the typo. Villavi-

cencio. Manuel Gonzales.

Distinguished by the eccentric, dark, lateral band.

Head 5; D. 12.5 (of which 4 minute); A. 9.5; P. 9; center of eye very little in
advance of middle of the head,-^ interocular three in the head. Teeth conic.

Nasal barbels extending to, or but slightly beyond, origin of pectoral; maxillary
barbel to the a.xil, equal to the length of the head; pectoral filament equal to the
length of the head, the longest ray equal to the length of the head behind the nasal
filament ; origin of ventrals equidistant from base of middle caudal rays and base or
tip of the interopercular spines, ventrals nearly reaching the anal; origin of the anal
under the last quarter of the dorsal, the distance between the base of its last ray
and the base of the middle caudal rays about 4.5 in the length; caudal rounded, six
and five-tenths to seven times in the length; the first rudimentary dorsal ray over
the base of the ventrals, its distance from the base of the middle caudal ray equal
to its distance from the tip of the opercular spine, 1.47 in its distance from the snout.

A dark band or row of spots from just above the gill-opening to the base of the
upix^r caudal lobe; a few spots below the band in the front half of the body in the
larger specimen.

This descrii)tion is based on the two larger specimens, 68 and 77 mm. long.
The two smaller specimens, 18 and 21 mm. long, are uniform in color.

39. Pygidium venulosum Steindachner.
Pygidium venulosum Steindachner, Anz. K. Akad. Wiss. Wicn, 1915, Xo. XVII,

p. 199 (Paramo de Cruz Verde, Eastern Cordilleras, Colombia, 3,000 M.)

Habitat. — Eastern Andes of Colombia.

I have not seen this species.

D. 10 or 11; A. 10; P. 8. Caudal peduncle greatly compressed. Caudal
rotmded; eye very small, a very little in front of middle of head. Barbels short,
about reaching eye; origin of anal under middle of dorsal; origin of dorsal equidistant
from tip of caudal and lateral margin of head; teeth pointed. First pectoral ray

^' In the plate the eye is placed too far forward; the anterior margin should be where the posterior
margin is.

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 321

not prolonged. Lateral band above middle of sides; back and sides with dark
reticulations on a lighter background.

40. Pygidium latistriatum Eigcnmann. (Plate XLVIII, fig. 4.)
Pygidium latistriatum Eigenmann, Proc. Am. Philos. Soc, LVI, Jan., 1918, p. 696.
7450, CM., type. 46 mm. Quebrada do Pinchote, Santander. Gonzales.

Head 8 mm., length to base of caudal 39 mm.; width of head 6 mm., interocular
2.5 mm., eye a little in front of the middle; distance from snout to origin of dorsal
23 mm., to its last ray 27 mm.; distance between origin of dorsal and base of middle
caudal rays 16 mm., distance from snout to origin of ventrals 22 mm., to origin of
anal 28 mm., distance between base of last anal ray and base of middle caudal
rays 9 mm., maxillary barbel 9 mm., nasal barbel 7 mm., length of outer pectoral
ray with its filament 8 and 9 mm., the divided rays 5 mm., D. 8.5; A. 6.5, not count-
ing the imbedded rays in either case; upper caudal rays 8 mm.; lower caudal rays
about 6.5 mm. Accessory caudal rays numerous.

A lateral band from above the opercle to the middle of the caudal, increasing
in width backward; mid-dorsal line dark; a dark stripe in front of the dorsal between
the lateral stripe and the mid-dorsal stripe.

It is possible that some of the specimens under P. nigromaculatum belong here.

41. Pygidium striatum Meek & Hildebrand.
Pygidium striatum Meek & Hildebrand, Field Mus. Publ., No. 166, Zool., Ser. X,

Dec, 1913, p. 78 (Rio Cana); Publ. 191, Zool., Ser. X, Dec, 1916, p. 266 (Rio

Cana), Tuyra Basin, Panama.

Habitat. — Colombia from Santander to the Rio Dagua in west central Colombia
and the Rio Tuyra in Panama.

I have been able to examine the types and the following specimens :

Catalog Numbers.

Number of

Spei'iiuens.

^^Sf,n*!'" ' Locality. Collector.

7113o-i, C.M. 13S20 I.U.M

7114a-6, C.M., 13S21 I.U.M

7115a-6, CM., 13822 I.U.M

710.5 C.M.,. .

41
5
4

2

,5

20

l(i

<J

1

79 largest Quebrada Sarjento
33-60 (iuebrada Alhan
41-61 Quebrada de la Ropera,

Santander
35 and 71 ' Quebrada do la llato,

Santander
.58 largest Guadual
,50 largest Villef a^
60 largest San Gil, Santander
43 largest Rio Guaduas
39 (Jucbrada ("lianiisal
45 1 Caldas, Rio Dagua

Gonzales.
Gonzales.

Gonzales.

710f)a-?;, G.M., 13S23 I.U.M

710.Sa-/l-, CM., 13,S24 I.U.M..

710!)a-i, CM., 13S2.5 I.U.M

7111a-(/, CM., 13S2S I.U.M

?7112, CM

Gonzales.
Gonzales.
Gonzales.
Gonzales.
Gonzales.

( Jonznlp,;

13829 I.U.M

1

Eigenmann.

Head 5-6; D. 10.5 or 11.5; A. 8.5 or 9.5; P.8; eye very little in advance of the

322 MEMOIRS OF THE CARNEGIE MUSEUM.

middle' of llic head, iuterocular 3.5 to 4 in tlie lengtli of tiic licad; tlie widtli of the
head equal to its length behind the nasal barbels.

Nasal barbels about reaching the tip of the opercular spines, the maxillary
barbels sometimes to the axil; first pectoral ray with its filament about equal to the
length of the head, the rays equal to the length of the eye and postorbital portion
of the head or a little longer ; origin of the ventrals equidistant from the base of the
middle caudal rays and some point in the basal half of the pectorals, their tips
i-caching the vent in the young, falling short in the adult; origin of anal under the
miildle of the dorsal, the distance between the base of the last ray and the base of
the middle caudal ray five to five and one-half in the length; caudal rounded, six in
the length; origin of the dorsal over some point in the last half of the ventrals,
equidistant between tip of caudal and middle of pectorals or a little farther forward,
its distance from the base of the middle caudal rays 1.8-2.2 in the length.

Sides and back spotted, the spots usually confluent into a narrow median lateral
liand and into a narrow band above and below the median band. The very young
with a narrow black lateral band without other markings.

The above description applies jjarticularly to the types and some of the speci-
mens between Honda and Facatativa, Nos. 7113, 7114, 7106, and some specimens
from Santander, No. 7105.

From these typical specimens the following variations were noted. In the
specimens fioni Villeta, No. 7108, also on the line between Honda and Facatativa,
the caudal is truncate with rounded outer edges, the origin of the dorsal is equi-
distant between the tip of the caudal and the operclc or a httle farther forward.
Home of these specimens are more distinctly spotted than the typical striatum,
approaching P. hanneaui.

In the specimens from Ciuaduas, also along the line l^etween Honda and
Facatativa, and in those from San Gil, No. 7109, the position of the dorsal agrees
with its position in those from Villeta, ('. c, it is in front of the typical position. In
these, the most conspicuous marking is a black lateral band in which the spots are
not recognizalile. In some of those from San Gil, the band above the median band
is also prominent, but it can sometimes be seen that both it and the median band
are made up of series of spots. A small specimen from Chamisal, No. 13831, is
nearly like them. The origin of the dorsal is median between the tip of the caudal
and the base of the opercular spines, the barbel extends nearly to the middle of the
jjectoral; a narrow black lateral stripe, otherwise plain light.

The specimens from La Ropera are more profusely covered with small spots,
their longitudinal arrangement inconsi)icuous.

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 323

In the specimen from Caldas, No. 13829, the origin of the dorsal is equidistant
from the tip of the caudal and the opercular spines. The spots along the middle
of the sides are conspicuous, but not confluent.

To this species probably also belong the following specimens.
7451a, C. ]\I., 13839, I. U. M., 3, largest 60 mm. Quebrada de la Pclada, San-

tander.
7452a, C. M., 13840, I. U. M., 2, larger 41 mm. Quebrada de la Callegona, San-

tander.
7453a-6, C. M., 13841, I. U. M., 3, largest 61 mm. Rio Mogotes, Santander.
7454a-c, C. M., 13842, I. U. M., 6, largest 63 mm. Quebrada de Horizonte, San-

tander.
7455a-d, C. M., 13843, I. U. M., 8, largest 67 mm. Quebrada de Suescum, San-

tander.

These are like the typical specimens of fitriatum described above, but lack all
color markings, being uniformly pale.

Very close to striatum if not identical with it, is P. regani.

42. Pygidium regani Eigenmann. (Plate XLVIII, fig. 5.)
Pygidium regani Eigenmann, Proc. Am. Philos. Soc, LVI, Jan., 1918, p. 696.
? Pygidium taenia Regan {non Kner & Rtcindachner), Ann. & Mag. Nat. Hist.

(8), XII, 1913, p. 469 (Rio Sipi and Rio Tamana).

Habitat. — San Juan basin.
13772, I. U. M., one, 55 mm. Tado, Rio San Juan. Purchased from Rosenberg.

Head 6; D. 10.5; A. 8.5; P. 8; eye in middle of the head, interorbital four
times in the length of the head.

Nasal barbel as long as the head, reaching beyond axil of pectoral; maxillarj-
barbel reaching to near the end of the lower pectoral ray, considerably longer than
the head; outer pectoral ray as long as the head; origin of ventrals equidistant from
base of middle ray and tip of opercle, not quite reaching to the vent; origin of an'^1
under posterior half of dorsal, the distance from the base of the last ray to the
middle caudal ray contained five and one-lialf times in the length; caudal six times
in the length; origin of dorsal equidistant from tip of caudal and opercular spines,
over posterior third of the ventrals, its distance from the middle caudal ray one
and four-fifths in its distance from the snout.

A dark streak from opercular spines to middle of caudal; faint spots above and
below the lateral stripe.

324 MEMOIRS OF THE CARNEGIE MUSEUM.

Table ok Measurements.

Length over all 55 mm.

Length to base of caudal 47 mm.

Length of head to tip of opercular spines S mm.

Distance of origin of dorsal from snout 30 mm.

Distance of origin of dorsal from middle caudal raj's 17 nmi.

Outer pectoral ray S mm.

Maxillary barbel 11 mm.

Nasal barbel 8 mm.

Length of eye 1 mm.

Length of snout 3.5 mm.

Interocular distance 2 mm.

This species is very similar to dridtuin, and may be a synonym of it.

43. Pygidium retropinne (Regan).
Trichomyclerus retropinnis Regan, Ann. & Mag. Nat. Hist. (7), XII, Dec, 1903,

p. G24 (headwaters of Magdalena east of Papaganat, St. Augustine, Andes of

Colombia, 5,000 ft.).

Habitat. — Headwaters of the Rio Magdalena.

"Length of head 5§ times in the total length. Head as broad as long. Diam-
eter of eye about 4 times in the interocular width, which is 3.33 times in the length
of the head. Snout as long as the postorbital part of head. Barbels equal to
about .8 the length of head. Dorsal with six branched rays, originating above or
slightly behind the anal opening, the distance from its i)oint of origin to the caudal
2.4 times in the distance from the former to the tip of the snout. Anal with 4
branched rays, originating below the anterior third of the dorsal, the distance from
the base of its last ray to the caudal 5.4 times in the total length. Longest branched
ray of the pectoral, .66 the length of the simple outer ray, which is equal to t the
length of head. Ventrals not quite reaching the anal opening. Caudal truncate-
rounded. Brownish, with an indistinct darker stripe along the middle of the side
and traces of some dark spots."

"Total length 80 mm."

"A third specimen, 30 mm. in total length, which I have purposely excluded
from the above diagnosis, has a well-marked broad longitudinal stripe on each side.
In it the longest branched ray of the pectoral is t the length of the outer simple ray,
and the distance from the origin of the dorsal to the caudal is 2.2 times in the dis-
tance from the former to the tip of the snout."

Key to the Species of Pygidium from the Amazon to the Essequibo.
From the vast lowland area (jf the Amazon, Orinoco, and (Uiiana but few species are known.
o. Origin of the dorsal in front of the vertical from the origin of the anal; maxillary barbel reaching tip

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 325

of opercle; snout about 2.5 in the head; nasal barbel reaching not quite to the tip of the maxil-
lary barbel; head nearly as wide as long; eye just in front of middle of the head.
b. Head 6 in the length; the first pectoral ray witii its filament equals the length of the head; sides
and back with numerous spots, each larger than the eye, in about five series between the dorsal
and anal; origin of dorsal equidistant from tip of caudal and eye ... .44. guianense Eigenmann.
bb. Head 5 in the length; first pectoral ray with its filament eciuals the length of the head without the
opercle; uniform yellowish-brown above, lighter below, top of head marbled; origin of dorsal

nearer tip of caudal than eye 45. conradi Eigenmann.

aa. Origin of anal under origin of dorsal.

c. Head 6 in the length; maxillary barbel reacliing tip of pectoral; upper parts obscurely spotted;
origin of dorsal equidistant from tip of caudal and middle of pectoral; eye in anterior half of

head 40. gracilior Eigenmann.

cc. Head 7 in the length; maxillary barbel reaching middle of pectoral; eye entirely in anterior half

of tlie head, nearly equal to the interocular and to the snout. . .47 amazonicum (Steindachner).

ccc. Head 5.5 in the length; maxillary barbel reaching tip of last interopercular spine; eye entirely in

anterior half of the head, considerably less than the interorbital or the snout; opercular and

interopercular bunch of spines alike 48. hasemani Eigenmann.

44. Pygidium guianense Eigenmann. (Plate L, fig. 1.)
Pygidium guianense Eigenmann, Ann. Carnegie Mus., VI, 1909, p. 11; Eigenmann,

Reports Princeton Univ. Exped. Patagonia, III, 1910, p. 400; Mem. Carnegie

Mus., V, 1912, p. 212 (Aruataima Cataract above Holmia.)

Habitat. — Upper Potaro River, British Guiana.
1003, C. M., tj^pe, 77 mm. Aruataima Cataract. Eigenmann.

Head 6; depth equals head in length; D. 9; A. 7; eye 4 in snout, 9.5 in head;
head nearly as broad as long; maxillary barbel reaching to tip of opercle; teeth in
bands of about four irregular series; origin of anal under middle of dorsal; dorsal
fulcra e-xtcnding forward to near the dorsal; caudal rounded; first pectoral ray pro-
longed in a filament nearly as long as the rest of the ray; round dark spots everj^-
where, except on belly and lower surface of head; caudal dusky, the margin light.

45. Pygidium conradi Eigenmann. (Plate L, fig. 2.)
Pygidium conradi Eigenmann, Mem. Carnegie Mus., V, 1912, p. 212 (Amatuk and

Waratuk Cataracts).

Habitat. — Lower Potaro River, British Guiana.
2212, C. M., 41 mm., type. Amatuk Cataract. Eigenmann.
11710, I. U. M., 34 mm., paratype. Waratuk Cataract. Eigenmann.

With the characters given in the key.

The teeth conic.

326 MEMOIKS OF THE CARNEGIE MUSEUM.

46. Pygidium gracilior Eiscnniiinii. (Plate L, fig. 3.)
Pygidiuni gracilior Eigenmann, Mem. Carnegie Mus., V, 1912, p. 213 (Erukiii).

Habitat. — Lower Potaro River, Briti.sh CJuiana.
1730, C. M., 27 mm., type. Erukin. Eigenmann.

Head 6; depth 9; D. 8; A. 6; eye about 2 in the snout; interorbital a little
greater than snout, snout 3 in tiic liead.

Slender, head as broad as long; maxillary barbel reaching tip of pectoral; nasal
barbel to origin of pectoral; outer pectoral ray prolonged, about equal to the head
in length. Origin of the anal under origin of dorsal; distance from origin of dorsal
to origin of caudal 3.5 in the; length; length of caudal 5 in the length.

All upper parts obscurely spotted.

47. Pygidium amazonicum (Steindachner). (Plate XLVI, figs. 3, 4.)
TricJiomyclerus aniazonicus Steindachntir, Flussf. Siidam., IV, 1882, p. 29, pi. VI,

figs. 4-4a (Cudajas).
Pygidium amazonicum Eigenmann & Eigenmann, Proc. Cal. Acad. Sci. (2), II,

1889, p. 53; Occasional Papers Cal. Acad. Sci., I, 1890, p. 338; Proc. U. S. Nat.

Mus., XIV, 1891, p. 37; Eigenmann, Reports Princeton Univ. Expcd. Pata-
gonia, III, 1910, p. 400.

Habitat. — Amazon, at Cudajas.

This species is known from the type, a specimen 60 mm. long.

Head a little over 6, equal to the depth; D. 8; A. 7; P. 6; eye entirely in front
of the middle of the head; interorbital a little greater than the eye; width of head
nearly equal to its length.

Head greatly depressed, caudal peduncle strongly compressed; nasal barbels
reaching nearly to gill-opening; maxillary barbel to the end of the first third of the
upper pectoral ray, lower barbel to the base of the pectoral; dorsal and anal opposite
each other; ventrals very short, 2 in the head; caudal rounded; upper pectoral ray
nearly equal to the head.

Chocolate brown, with faint darker spots on the caudal iDeduncle; rays of dorsal
and caudal dotted with violet.

48. Pygidium hasemani Eigenmann. (Plate L, fig. 4.)
Pygidium hasemani Eigenmann, Ind. Univ. Studies, No. 20, March, 1914, p. 48.
5238 and 5239, C. M., type and paratypes, many, largest under 18 mm. Santarem.

Haseman.

Habitat. — Amazon at Santarem to Bolivia.
76023, C. M., about 16 mm. San Joaquin. Sept. 4, 1909. Haseman.

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 327

Head 5.5; D. 7 or 8; P. 6. Eye in anterior half of the head, about five times
in the length of the head, less than the snout, about two times in interorbital. Teeth
conical, in a single series; maxillary barbel extending to the tips of the interopercular
spines; axillary glands large; opercular and interopercular bunches of spines similar,
separate from each other; gill-membranes united, free from the isthmus; pectoral
very narrow, about equal to the head in length, the first ray prolonged; origin of
dorsal over origin of anal, its distance from the base of the caudal two in its distance
from the eye or occiput, equidistant from tip of caudal and middle of pectoral;
origin of ventrals nearer snout than tip of caudal; caudal rounded, merging into
the large accessor}- rays.

Translucent, with many chromatoi)hores; dusky spots on the back from a short
distance in front of the dorsal to the caudal ; a dark bar across ba.se of caudal ; dark
spots, similar to those of the back, from between ventrals and anal to the caudal; a
series of minute spots along the middle of the sides; a small spot on opercle, another
on the interopercle, a dark line forward from the eye; a minute spot on base of
ventrals.

Species from Southeastern Brazil.

The mountain brooks of southeastern Brazil from Rio Grande do Sul to the
Rio San Francisco harbor a number of species. One of these, P. iheringi, has
broad incisors, a number arc knowii to have pointed teeth, while the rest, nigricans,
niinutum, goeldii, itatiaycv and punctatissimum, I have not been able to examine.
They have the following distribution :

P. mimitum Southern Rio Grande.

P. nigricans Santa Gatherina.

P. davisi Rio Iguassu, southern Sao Paulo.

P. proops Ribeira, southern Sao Paulo and Rio Parahyba.

P. iheringi Ribeira, Santos, and Sapina, Sao Paulo.

P. paolence Northern Sao Paulo.

P. goeldii Parahyba basin.

P. vermiculatinn Parahyba basin.

P. imviaculatum Parahyba basin; Sao jMatheos; Goyaz.

P. brajiliense ? Rio Grande do Sul, ? Rio Ribeira; Rio das Velhas; Rio Doce.

P. itatiayce Parahyba basin.

P. triguttatum Parahyba basin.

P. rcinhardti Burmier, into Rio das Velhas.

P. alternatiim Rio Doce.

P. punctatissimum Araguay.

P. santce-ritcc Rio Preto.

328 MEMOIRS OF THE CARNEGIE MUSEUM.

Key to the Species of Pygidium found in Southeastern Brazil.
a. First dorsal ray prolonged in a filament; barbels scarcely reaching the edge of ej-e; back uniform

blackish, lower parts light; D. 11; A. 10; P. 9 49. nigricans (Cuvier & Valenciennes).

aa. First dorsal ray not prolonged; teeth incisors; origin of dorsal equidistant from tip of caudal and a
point between the eyes and nasal barbels.
b. First pectoral ray not prolonged, or with onlj- a trace of a projection; first anal ray behind the

dorsal; sides and back with numerous spots 50. iheringi Kigenmann.

bb. First pectoral ray usually prolonged; first anal ray under the dorsal; markings conspicuous.

51. zonatum Kigenmann.
aaa. First dorsal ray not prolonged; teeth conical.-*

c. Origin of the dorsal nearer to the tip of the caudal than to the head, or sometimes equidi.stant
between tip of caudal and occiput in P. paolence.
d. Origin of the anal under the second dorsal ray, last dorsal ray over middle of anal; origin of
vcntrals nearly equidistant from tip of caudal and snout; eye in anterior half of the head,

near the posterior nares; head 5. .5-6; D. 9; A. 7-9 52. proops (Ribeiro).

(Id. Origin of the anal under the middle of the dorsal, last dorsal ray over third anal ray; origin
of vcntrals nearer to tip of caudal than to tip of the snout; eye just in front of the
middle of the head; head six times in length.
e. D. 8.5; A. fi.5; many faint .spots, a dark streak along the middle of the sides, another

above it 53. paolence Kigenmann.

ee. D. 9.5; A. S.5; a broad lateral bantl with serrate edges; a series of spots below it and

another above it 54. reinhardti Kigenmann.

ddd. Dorsal opposite the space between ventrals and anal. (See No. 59 goeldii.)
cc. Origin of the dorsal equidistant between the tip of the caudal and some point near the eye."
/. Pectoral ray without a filament; origin of ventral nearer snout than tip of caudal; origin of
anal under posterior part of dorsal; color variable; D. 7; .\. 5..55. davisi Haseman.
//. First pectoral ray usually jirolonged as a filament.

g. Color plain; anal behind the dorsal; origin of ventral nearer snout than tip of caudal;
caudal very slightly emarginate; eye in the middle of the head; D. 11.5-13; A. 9.5-

10.5 56. immaculatum Eigenmann & Kigenmann.

gg. Variously marked.

h. Origin of the anal under posterior half of the dorsal.

i. Origin of the dorsal over the origin of the venlrah; origin of the ventrals nearer
tip of caudal than ej'e; ventrals reaching anal; D. 8.5; A. 8.5; eye in middle
of he.ad; sides and back profusely covered with confluent spots, leaving the
ground-color in irregular vermiculations. See also puctalissimum.

57. vermiculatum Kigenmann.
it. Origin of the dors.il behind the origin of the ventrals.

j. Sides and back with large spots, sometimes alternating across the back;
origin of ventrals equidistant from snout and middle of caudal; dis-
tance between origin of dorsal and caudal about 1.5 in distance of
dorsal from the snout; caudal subtruncate; D. 10.5-11.5; A. 7.5 or S.5.

58. alternatum Eigenmann.
^' Mot examined in P. mivutum, nigricans, goeldii, and punctatixsimum.
" Not examined in P. goeldii.

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 329

jj. With ill-tlefined spots; origin of vcntrals equidistiuit from snout and tip
of caudal; caudal rounded; distance between origin of dorsal and
caudal twice in its distance from the snout; D. 10; A. 7.

59. goeldii (Boulenger).

jjj. With small spots and vermiculations; origin of ventrals equidistant from

snout and tip of caudal; distance between origin of dorsal and caudal

1.66-1.75 in distance of dorsal from the snout; D. 10.5 or 11.5; A. 7.5

or 8.5 60. brasiliense (Rcinhardt).

jjjj. A dark lateral band, spots above and below it; origin of vcntrals a little
nearer snout than to tip of caudal ; distance between origin of dorsal and
caudal I.S in distance of dorsal from the snout; caudal truncate.

()1. itatiayse (Ribeiro).
hh. Origin of the anal behind the vertical from the last dorsal ray, the dorsal ojjposite
the space between the ventral and anal, its origin equidistant from snout and
tip of caudal, or nearer one or the other; origin of ventrals nearer the snout than
to the tip of the caudal; intcropcrcle with aI)out seven spines in a bunch similar
to that of the opercle; a series of dots along the middle of the sides, another along

the back and another between the two 62. triguttatum Eigenmann.

ccc. Origin of dorsal equidistant from tips of snout and caudal; pectorals witliout filaments; dorsal
entirely in front of the anal.
k. Sides and back with minute dark specks and vermiculations between them; origin of dorsal

ov£r origin of ventrals 63. punctatissimum (Castelnau).

kk. Pale brown above with three longitudinal series of squarish brown blotches; origin of dorsal

over middle of ventrals; head 4.5 in the length G4. minutum (Boulenger).

cccc. Origin of dorsal nearer snout than to tip of caudal.

I. Nasal barbels not quite reaching eye, maxillary barbel little beyond posterior margin of the
eye; dorsal entirely in front of anal; sides with large blotches. Head four times in the
length; a long patch of interopercular spines; pectoral ray not prolonged.

65. santae-ritae Eigenmann.
II. Nasal barbels reacliing beyond origin of eye; pectoral ray prolonged.

m. Interopcrclc with a long patch of sjiines; pectoral ray prolonged. (See P. alkrnalum,
No. 56.)
mm. Interopercle with about seven thorns in a patch .similar to that of the opercle; end of
dorsal over anus; pectoral ray much prolonged. (See P. iriguttalum, No. 60.)

49. Pygidium nigricans (Cuvier & Valenciennes.)
Trichomycterus nigricans Cuvier & Valenciennes, Hist. Nat. Poiss., XVIII,
1846,. p. 494; ? Gay, Hist. Chile, 1848, p. 311 (Chile); Gunther, Cat. Fishes
Brit. Mus., V, 1864, p. 274 (copied); Ribeiro, Fauna Brazilicnse, Peixes,
IV (A), 1912, p. 220.
Pygidium nigricans Eigenmann & Eigenmann, Proc. Cal. Acad. Sci. (2), II, 1889,
p. 53; Occasional Papers Cal. Acad. Sci., I, 1890, p. 338; Proc. U. S. Nat. IMus.,
XIV, 1891, p. 37; Eigenmann, Reports Princeton Univ. Exped. Patagonia,
III, 1910, p. 400.

330 MEMOIRS OF THE CARNEGIE MUSEUM.

Habitat. — Santa Cathcrina, Brazil.

^'alcncionncs's description of the only specimen known, 140 mm. long, is very
brief, and I am afraid that it is in part misleading.

"D. 11; A. 10; P. 9; barbels short, scarcely reaching beyond the eyes; caudal
pedimcle short and deep; caudal small, truncate, 'le premiere rayon de la dorsal
alonge en fil.'

"Back uniform blackish, lower parts light."

50. Pygidium iheringi Eigenmann. (Plate L, fig. 5.)
Piigidium iheringi Eigexm.^nn, Proc. Am. Philos. Soc, LVI, Jan., 1918, \). 697.
Trichomycterus punctulatus (nan Cuvier & Valenciennes) Ribeiro, Arkiv. for

ZoiJlogie, IV, No. 19, 1908 (Iporanga). •
Trichomyctenis dispar {non Tschudy) Ribeiro, Kosmos, V, 1908, and Fauna Brasi-

liense, IV (A), 1912, p. 222 (Rio Iporanga, Sao Paulo).

Habitat. — Sao Paulo in coastal streams and the Parana basin.
7071, C. M., two, 151-lCO mm. Sapina, Sao Paulo. July 3, 1908. Haseman.
10785, I. U. M., four, 140-161 mm. Santos. Von Ihering, the largest the t>i3e.

Allied to P. punctati.'isinunn from the Araguay.

Head 4.5-5 in the length; D. 11.5 or 12.5; A. 7.5 or 8.5 counting the two rudi-
mentary raj'S in each case; P. 8; width of head equal to its length behind the nasal
barbel; eye in middle of the head, interorbital 3.5-4 in the length of the head.
Teeth incisors with slightly expanded tips, in bands of four or five series.

Nasal barbels reaching about to middle of eye, axillary barbel to above middle
of opercle; pectoral rounded, very little longer than snout and eye, the first ray not
prolonged or with only a trace of a projection ; distance between origin of ventrals
and eye a little gi-eater or less than that between origins of ventrals and middle
caudal rays; the ventrals as long as the snout, not nearh' reaching vent, nearly
halfway to the anal; origin of anal on, or behind, the vertical from the base of the
last dorsal ray; distance between bases of last anal raj' and middle caudal rays five
or a little over five in the length; caudal slightly rounded, seven to seven and a
half in the length; dorsal low and long, the distance between its origin and the base
of the middle caudal ray about one and a third in its distance from the snout, its
first ray over posterior half of the ventrals.

Sides and back with numerous spots, smallest over pectorals, largest over
dorsal, rarely coalescent.

51. Pygidium zonatum sp. nov. (Plate LI, fig. 1.)
7.596, C. M., a, the type, 62 mm., b and c, paratypes, 50 and 55 mm. Agua Quente.
Nov. 27, 1908. Ha.seman.

EIGENMANN: the PYGIDIIDiE, A FAMILY OF SOUTH AMERICAN CATFISHES. 331

7595, C. M., paratype, 60 mm. Cubatao, seven miles west of Santos, Sao Paulo,

Brazil. Aug. 1, 1908. Haseman.

In all but the teeth and color very similar to P. davisi.

Head 5; depth 6-6.5; D. 10; A. 7 or 8; P. 7 or 8; eye three times in the snout,
seven to seven and one-half times in the head, two times in the intcrocular, exactly
in the middle of the head or a little in front of it; posterior nares more than an or-
bital diameter from the eye; three rows of narrow incisors in each jaw. The teeth
of the paratypes nearly conical.

Maxillary barbel reaching to near tip of last interopercular spine or to tip of
opercular spines, the nasal barbel but little shorter; head pointed, but little longer
than broad; gill-openings extending forward to below the anterior interopercular
spines. First pectoral ray but slightly, if at all, prolonged, its length with the
filament equal to the head without the opercular spines; origin of ventrals about
equidistant from the snout and the middle of the caudal; origin of anal mider
penultimate, or fourth from last, dorsal ray; distance between liases of last anal ray
and middle caudal rays four and one-half to five in the length; caudal truncate;
origin of dorsal over last third of the ventrals, its distance from the base of the mid-
dle caudal rays 1.5-1.75 in its distance from the snout.

Color-markings coarse and conspicuous. In No. 7595 C M., five obscure
bars across the back in front of the dorsal, shghtly emphasized at their lower ends
on the middle of the sides; three similar bars behind the dorsal; a dark fine from
anterior to posterior nares. In the specimens from Agua Quente a dark lateral
band broken toward the caudal in the smallest. Back and lower part of the sides
with conspicuous spots.

52. Pygidium proops (Ribeiro). (Plate LI, fig. 2.)
Tricomyderus proops Ribeiro, Kosmos, V, 1908, fig. 4; Fauna Brasiliensc, Peixes,
IV (A), 1912, p. 221, pi. XL, fig. 1.

Habitat. — Ribeira de Iguape, southern Siio Paulo, Brazil, and Rio Parahyba.
Known from the types, and from
7593, C. M., one, 60 mm. Agua Quente, Ribeira Basin. Nov. 27, 1908. Hase-
man.
7598, C. M., one 32 mm. Sao Joao da Barra, Rio Parahyba. June 22, 1908.
Haseman.

Head 5.5-6; depth 7; D. 9; A. 7-9; P. 7; posterior margin of eye slightly in
advance of the middle of the head, diameter of eye two times in the snout, six and
one-half in the head, over one and one-half in the interorbital; posterior nares close
to the eye, their posterior margin on a line with (he anterior margin of the eye;

332 MEMOIRS OF THE CARNEGIE MUSEUM.

teeth conical, in very narrow bands; nasal barbels reaching to the base, maxillary
barbels to the tips of the opercular spines; first pectoral ray not prolonged, pectoral
equal to the Iciigtii of the head without the snout; origin of ventrals equidistant

♦.•-•,,••», .. . ■;j.'»»,:»^ ■ .

Fi«. If). Pi/gidium proiipK (Rili^o). No. 75it:5 CM. EWWr^

from tip of snout and tip of caudal; origin of anal under second or third dorsal ray;
distance between last ray of anal and base of caudal five and one-third times in
the length; caudal rounded; distance between origin of dorsal and caudal two and
one-half times in its distance from the snout.

Back, sides, dorsal and caudal densely spotted.

The above description is based on the specimen from Agua Quente and Ribeiro's
account; the smaller specimen from the Parahyba has:

Head 5; depth 8; D. 10; A. 9; P. 5; first pectoral ray considerably prolonged;
origin of ventrals equidistant from tip of caudal and pre-opercle. Sides and back
finely marbled, a faint dusky, lateral fine, and another above it. Its prolonged
first pectoral ray and narrow pectoral, with but five rays indicate a distinct variety,
which may be called parahybw, var. nov.

53. Pygidium paolence Eigenmann. (Plate LI, fig. 3.)^*
Pygidium paolence Eigenmann, Proc. Am. Philos. Soc, LVI, Jan., 1918, p. 698.

Very close to Trichomycterus proops Ribeiro.
7081, C. M., type, 68 mm. Alto da Scrra, Rio Tiete, Sao Paulo. July 25, 1909.

Haseman.
7597, C. M., paratype, 61 mm. Rio Paranahyba bridge. Aug. 15, 1908. Hase-
man.

Head 5.33-6; D. 8.5; A. 6.5-8 not coimting hidden rudiments, D. 10.5 and
A. 8.5 with the rudiments; P. 6 or 7; head nearly as wide as long; eye in anterior
half of the head, greater than its distance from the posterior nares; snout 2.33-2.5
in the length of the head, interocular 3-3.5; teeth conic; nasal barbel reaching base
or tip of opercular spines, maxillary barbel reaching tip of opercular spines or a
little farther; outer jicctoral ray with its filament equal to head behind the posterior

^ The head is too short in tliis drawing.

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 333

nares, the filament extending very little beyond the other rays; ventrals nearly
reaching anal, their origin nearer caudal than to tip of pectorals; caudal rounded,
six in the length; origin of anal under middle of dorsal, distance between the base
of its last ray and the middle caudal ray 5.2 in the length; origin of dorsal eciuidis-
tant from base of middle caudal rays and middle of pectorals, its last ray over the
middle of the anal, the distance between the origin of the dorsal and the base of the
middle caudal rays two in the distance between dorsal and snout in the tyiie, 1.66
in the paratype.

With many faint spots about as large as the eye; in the tj'pe a dark streak along
the middle of the sides, another along the side of the back, and a third along the
edge of the belh'.

This species is similar in appearance to P. striatum, from which it differs in the
position of the ventrals, the pectoral filaments, etc.
7117a-i, C. M., ten, 25-30 mm.. Mogy das Cruces, Rio Tietc, July 20, 1908.

These minute specimens came from near the type locality of P. paolence and
are probably the young; the ventrals do not reach the vent; there is a series of
minute spots along the sides, nearly confluent anteriorly; a series of larger spots
above it on the sides of the back and a series along the middle of the back.

54. Pygidium reinhardti Eigenmann. (Plate LI, fig. 4.)
Pygidium reinhardti Eigenmann, Proc. Am. Philos. Soc, LVI, Jan., 1918, p. 699.
7078, C. M., one, 65 mm. Burmier on the Rio Itabira, a tributary of the Rio das

Velhas. May 14, 1908. Haseman.

Mr. Haseman notes that this is the only species he secured at the particular
locality where the only specimen of the present species was collected.

Head 6.5; D. 9.5; A. 8.5, counting the minute rudimentary rays in both dorsal
and anal; P. 6; eye in anterior half of head; interocular three times in the head.
Teeth conic.

Nasal barbel nearly as long as the maxillary barbel, which reaches the edge of
the gill-membrane. First pectoral ray with its filament equal to the length of the
head, much longer than the divided raj's; ventrals reaching beyond the vent, their
origin verj' little nearer tip of pectorals than base of middle caudal rays; origin of
anal under middle of dorsal; distance between the base of the last anal raj' and the
middle caudal raj^s five and a half in the length; caudal narrow, a little longer than
the head, the accessory rays inconspicuous; origin of dorsal over middle of ventrals,
its distance from the middle caudal rays nearlj' two in its distance from the snout
(19 and 36 mm. respectively).

334 MEMOIRS OF THE CARNEGIE MUSEUM.

A broad, dark stripe Avith notched edges from opercle to middle of caudal,
bordered above and below by light bands; an irregular series of spots below the
lower light band ; a series of small spots more or less confluent forming a narrow,
dark stripe above the upper light band; back and fins lightly spotted, a short dark
hiir in front of the opercle, a longer one above middk^ of jire-opercle.

55. Pygidium davisi Hascman. (Plate LI, fig. 5.)
]\tj(jidiu>n davisi II.vseman, Ann. Carnegie Mus., VII, 1911, p. 380, i)l. LXXVII,

fig. 1, and pi. LXXVII.

Habitat. — Coastal streams of southern Sao Paulo.
2862, and2 861, C. M., type and paratypes. Rio Iguassu near Serrinha Parana.

Dee. 23, 1908. Haseman.
7UQa-d, C. M., 52-60 mm. Morretes, Parana, Brazil. Jan. 4, 1909. Hascman.

Head 5.5; D. 7; A. 5 without the imbedded rays; D. 10; A. 9 with the imbedded
rays; P. 8; oyc sHghtly in advance of the middle of the head; interocular four times
in the length of the head; teeth conic.

Nasal barbel as long as the labial barbel, extending to the base of the opercular
spines, maxillary barbel to their tips; pectorals shorter than the head, the first ray
not prolonged; origin of ventrals equidistant from tip of snout and tip of caudal or
nearer the former, not reaching the vent; origin of anal under the posterior part
of the dorsal, the distance between its last ray and the base of the middle caudal
rays about five in the length; caudal subtruncate, five and one-half in the length;
origin *of the dorsal over last half of the ventrals, equidistant between the tip of the
caudal and the nasal barbels or eye ; the distance between it and the caudal one and
six-tenths in its distance from the snout.

Uniform light or dark, or mottled, sometimes with a dark lateral band with
one or more series of blotches above it.

56. Pygidium immaculatum Eigenmann & Eigenmann. (Plate LII, fig. 1.)^'
Pygidium immaculatum Eigenmann & Eigenmann, Proc. Cal. Acad. Sci. (2), II,

1889 (Juiz de Fora; Sa,o Matheos; Goyaz); Occasional Papers Cal. Acad.

Sci., I, 1890, p. 337; Eigenmann, Report Princeton Univ. Exped. Patagonia,

III, 1910, p. 400.
Trichomycterus immaculatus Ribeiro, Fauna Brasiliense, IV (A), 1912, p. 222.

Habitat. — Rios Parahyba and Doce. Goyaz.
7076a-6, C. M., two, 81-93 mm. Rio Doce. May 24 and 25, 1908. Haseman.

" The head is n little too sliort in the figure.

EIGENMANN: the PYOIDIIDiE, A FAMILY OF SOUTH AMERICAN CATFISHES. 335

Head 4.75-5; D. 11.5-13; A. 9.5-10.5; P. 8 or 9; eye in tiie middle of the head
or very nearly so, interocular 4-4.5 in the head. Teeth conic.

Nasal barbels extending to the middle of the interojicrcle, maxillary barbel
about to opercular spines; pectorals but little longer than snout and eye, the first
ray with its filament equal to head behind the nasal barbel ; ventrals reaching vent,
their origin very little nearer caudal than to eye; origin of anal just behind the
vertical from the base of the last dorsal ray or under the penultimate ray, distance
between the base of its last ray and the base of the middle caudal ray four and a
half to five times in the length; caudal very slightly emarginate, about seven times
in the length; origin of dorsal over posterior part of the ventral, its distance from
the base of the middle caudal rays one and two-thirds times in its distance from the
snout.

Sides and back uniform, without trace of spots or vcrmiculations; middle caudal
rays dusky.

57. Pygidium vermiculatum Eigcnmann. (Plate LII, fig. 2.)
Pygidium vermiculatum Eigenmann, Proc. Am. Philos. Soc, LVI, Jan., 1918,

p. 699.
Pygidium brasiliense {non Ltitken) Ribeiro (partim), Fauna Brasiliense, IV {A),

1912, p. 225 (the specimens from Juiz de Fora).

Habitat. — Rio Parahyba.
7074, C. M., one, 131 mm. Juiz de Fora. June 9, 1908, presented by Dr. Ribeiro.

In general appearance hke Liitken's figure of brasiliense, differing notably in
the position of the ventrals.

Head 5.4 in the length; D. 8.5; A. 8.5 (counting in each case the two rudi-
mentary rays); P. 7; width of the head nearly equal to its length; eye in middle of
the head, interorbital three in the length of the head. Teeth conic, in bands.

Right nasal barbels reaching to above base of the opercular spines, maxillary
barbels of right side nearly as long as head, reaching to the second fourth of the
pectoral, both shorter on left side; pectoral rather narrow, the outer ray much pro-
longed, as long as the head behind the nasal barbel, the fin without the filament
equal to the part of the head behind a point midway between eye and posterior
nares; origin of ventrals under origin of dorsal, equidistant between base of middle
caudal rays and last third of pectorals, ventrals reaching much beyond vent,
almost to anal, as long as the snout; origin of anal under {lenultimate ray of the
dorsal, distance between the base of its last ray and the base of the middle caudal
ray a little more than five in the length; caudal rounded, six and one-third in the
length; dorsal short, rounded, the distance between its origin and the base of the

336 MEMOIRS OF THE CARNEGIE MUSEUM.

middle caudal rays oiio and sixty-seven hundredths in the distance between its
origin and the snout.

Sides and back profusely covered with confluent spots, which leave the light
color as irregular vermiculations.

58. Pygidium alternatum Eigenmann. (Plate LII, fig. 3.)
Pygidmm alternatum Eigenmann, Proc. Am. Philos. Soc, LVI, Jan., 1918, p. 700.
Pygidium brasiliensis Eigenmann & Eigenmann (partim), Proc. Cal. Acad. Sci.

(2), II, 1889, p. 51; id. (partim), Occasional Papers Cal. Acad. Sci., I, 1890, p.

332; Ribeiro (partim), Fauna Brasiliensis, IV (A), 1912, p. 223.

Habitat. — Rio Doce.

It is possible that the young specimens of P. brasiliensis mentioned by Eigen-
mann & Eigenmann belong to this species.

7079, C. M., tyi)e and paratypes, sixty-seven, largest 81 mm. Rio Doce, May 25,
1908. Haseman.

7080, C. M., eleven, largest 49 mm. Rio Doce, May 25, 1908. Haseman.
7601rt, C. M., 26 mm. Jacarehy, July 15, 1908. Haseman.

Head 5-5.5; D. 10.5-11.5; A. 7.5 or 8.5 counting the rudimentary rays ; P. 7 or
8; eye in middle of the head or slightly farther forward; interocular 3-3.33 in the
length of the head. Teeth conic, in bands.

Nasal barbel very little shorter than maxillary barbel, which reaches to the
base of the pectoral and is as long as the head; pectoral rays equal to length of head
l)ohind the nasal barbels, the first ray with the filament longer than the head;
ventrals reaching to, or just beyond, vent; origin of ventrals equidistant from base
of middle caudal rays and a point between the posterior nares and the area just
behind the eyes; origin of anal under posterior part of dorsal; distance between base
of last anal ray and middle caudal raj's four and a half to five and a third in the
length; caudal subtruncatc or rounded, very little longer than head; origin of dorsal
over posterior half of ventrals; distance between origin of dorsal and base of middle
caudal rays 1.54 in its distance from the snout.

Ten to fourteen large spots along the middle of the sides, an irregular series
of much smaller ones below it. Large spots above the median series, frequently
alternating with it, sometimes partly confluent into a longitudinal series, some-
times forming with a mid-dorsal series irregular bars across the back.

As the specimens, No. 7079, ranging up to 8rmm., are essentially ahke in color
and entirely different from the specimens of both smaller and larger size (74-120
mm.) from the same place referred to P. brasiliense, No. 7075, they have been

EIGENMANN: the PYGIDIIDiE, A FAMILY OF SOUTH AMERICAN CATFISHES. 337

separated from the latter species. They may be identical with some of the younger
specimens of P. hrasiliense mentioned by Eigenmann & Eigenmann in the papers
quoted above.

The specimens, No. 7080, are much shriveled but probably belong to this

species.

59. Pygidium goeldii (Boulenger).

Trichomycterus yoeldii Boulenger, Ann. ]\Iag. Nat. Hist. (6), XVIII, 1890, p. 154.

Habitat. — Colonia Alpina, Therczopolis, nearly 2,600 ft., near Rio de Janeiro.

I give the original description of Boulenger, /. c. :

"Head much depressed, as long as broad, six times in total length; eye small,
midway between end of snout and opercular border, its diameter half interorbital
width; upper maxillary barbel reaching the pectoral; gill-membranes narrowly
joined to the isthmus, extending forward to below the eyes. Body as deep as
broad; caudal peduncle strongly compressed, twice as long as deep. Dorsal with
10 rays, opposite to the space between ventrals and anal, twice as distant from the
end of the snout as from the caudal; anal with 7 rays. Pectorals with the outer
ray produced, filiform. Ventrals equally distant from the end of the snout and
the posterior border of the caudal fin ; latter rounded. Yellowish, with ill-defined
brown spots above. Total length 99 millim."

60. Pygidium brasiliense (Reinhardt).

Trichomycterus brasiliensis Reinhardt MS. in Liitken, Overs. Dansk. Mdensk.
Selsk., 1879, No. 3, p. 29 (Rio das Velhas); Lutken, Velhas Flodens Fiske,
p. 15, in Vidensk. Selsk. Skr. (5), Afd., XH, 1875, pp. 135 and I, pi. HI, fig. 8
(Rio das Velhas); ? Boulenger, Proc. Zool. Soc. London, 1891, p. 235 (Rio
Grande do Sul) ; Ribeiro, Kosmos, 1908 (Ribeiro) ; Archiv. :\Ius. Nac. Rio de
Janeiro, XIII, 1906 (p. 7 of reprint); Fauna Brasiliense, Peixes, IV (A), 1912,
p. 223, Arch. Mus. Nac. Rio de Janeiro, XVI.

Pygidium brasiliensis Eigenmann & Eigenmann (partim), Proc. Cal. Acad. Sci.
(2), II, 1889, p. 51; Occasional Papers Cal. Acad. Sci., I, 1890, p. 332; Proc.
U. S. Nat. Mus., XIV, 1891, p. 36; Eigenmann, Reports Princeton Univ.
Exped. Patagonia, III, 1910, p. 399.

Trichomycterus brasiliensis tristis Lutken, I. c, p. 138, with figure, and p. I.

Habitat. — Rios das Velhas and Doce south to Ribeira do Iguapc and ? Rio

Grande do Sul.

7594, C. M., four, 71-87 mm. Rio das Velhas. May 13, 1908. Haseman.

7550, C. M., one, 133 mm. Burmier. May 14, 1908. Haseman.

7075, C. M., fourteen, 74-120 mm. Rio Doce. May 25 and 27, 1908. Haseman.

338

MEMOIRS OF THE CARNEGIE MUSEUM.

Head 4.75-5 in the length; D. 10.5 or 11.5; A. 7.5 or 8.5 counting the rudi-
mentary rays; P. 7; width of head very nearly equal to its length; eye in the middle
of the head or partl>" in the anterior half; interocular 3-3.33 in the lenglh of the
head. Teeth conic.

Fig. 17. Pijgtdium brasiliense (Reiuhanlt). After Liitken.

Nasal barbels extending to a point above the end of the interopercle, maxillary
barbel to the giU-opening, or very Uttle shorter or longer; jiectoral a little longer
than snout and eye, the first ray being ver}' little prolonged in the smallest, equal
to the length of the head less the opercle in the largest; origin of ventrals equidistant
from base of middle caudal ra.vs and base of pectoral in the specimen from Burmier,
or to a point between the eyes and the opercle in the others, reaching very little be-
yond the vent, about two-thirds to anal, or to the anal in the specimen from Burmier;
origin of anal below posterior half of dorsal, the distance between the base of its
last ray and the base of the middle caudal rays four and two-thirds to five and a
quarter in the length; caudal rounded, five and a half to six and a half in the length;
origin of dorsal over posterior half or end of ventrals, the distance between its
origin and the base of the middle caudal raj^s one and two-thirds to one and three-
fourths times in the distance between its origin and the snout.

Fit;. IS. Pygidium brasiliense (Reinhardt). Opercle and P. brasiliense trisle (Liitkeu).

The color in the specimens from the Rio Doce is the same. Back and sides
with numerous spots and vermiculations, the spots forming an irregular dark Hne
along the middle of the sides in front. The spots and vermiculations are a little
finer than in Liitken 's figure of brasiliensis. In the specimens from Burmier and
the Rio das Velhas there is a distinct median lateral band, the markings below it
being coarse. In the largest the lateral band becomes obscure.

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 339

61. Pygidium itatiayae (Ribeiro).
Trichomycterus brasiliensis itatiayoe Ribeiro, Archives Mus. Nac. dc Rio dc Janeiro,

XIII, 1906, p. 8, pi. I; Fauna Bras., IV (A), 1912, p. 223.

Habitat. — Itatiaya, Serra da Mantiqueira.

Caudal subtruncato; head longer than broad; last ray of the dorsal over the
fourth of the anal; a dark lateral band.

July

Fiu. 19. Pygidium ilatiayw (Ribeiro), adult and young. After Ribeiro.

62. Pygidium triguttatum spec. nov. (Plate LII, fig. 4.)
7600, C. M., a the type 36 mm., b to c, paratypes 26-34 mm. Jacarehy.

14 and 15, 1908. J. D. Haseman.

Readily distinguished by the few spines in the interopercle.

Head 5-5.5; D. 8 or 9; A. 6 or 7.5; P. 6; eye in anterior half of the head, 2 in
the snout, 6 in the head, about 1.5 in the interorbital; teeth pointed, in very narrow
bands; gill-openings reaching forward to below the eye; nasal barbels reaching to
tip of opercular spines, or but little beyond the eye; maxillary barbels to the base
of the opercular spine or to the axil; pectorals lanceolate, the first ray much pro-
longed, one and a third times as long as the head in the type, longer than the head
in all but one of the paratypes; origin of ventrals equidistant from snout and middle
of caudal; tips of ventrals reaching anus in two of tho specimens, falling consider-
ably short of the anus in the rest; origin of anal behind the dorsal; distance between
last anal ray and caudal 5-5,5 in the length; caudal rounded, but few inconspicuous

340 MEMOIRS OF THE CARNEGIE MUSEUM.

accessory rays; distance from origin of dorsal to base of middle caudal rays 1.2-1.4
in the distance between snout and dorsal; distance from origin of dorsal to tip of
caudal sometimes less, sometimes greater, than its distance from the snout.

A row of small spots along the middle of the sides, another along the middle
of the back and a third between the two.

63. F*ygidium punctatissimum (Castelnau). (Plate XLV, fig. 1.)
Trichomycterus pxinctatissimus Castelnau, Anim. Nouv. Am. Sud., 1855, p. 49,

pi. 24, fig. 3, GtJNTHER, Cat. Fishes Brit. Mus., V, 1864, p. 272; Ribeiro,

Fauna BraziHense, Peixes, IV (.4), 1912, p. 221.
Pygidium jmnctatissimum Eigenmann & Eigenmann, Proc. Cal. Acad. Sci. (2),

II, 1889, p. 52; Occasional Papers Cal. Acad. Sci., I, 1890, p. 334; Proc. U. S.

Nat. Mus., XIV, 1891, p. 36; Eigenmann, Reports Princeton Univ. Exped.

Patagonia, III, 1910, p. 399.

Habitat. — Rio Araguay.

Ivnown from the types, with the characters given in the Key.

64. Pygidium minutum (Boulenger).
Trichomijcterus mimdus Boulenger, Proc. Zool. Soc. Lond., 1891, p. 235, pi.

XXVI, fig. 3.
Pygidium minutum Eigenmann, Reports Princeton Univ. Exped. Patagonia, III,

1910, p. 399.

Habitat. — 8an Lorenzo district, southern Rio CJrande do 8ul.

Fh!. 20. Pygidium minutum (Boulenger). After Boulenger.

Head 4.5; D. 8; A. 6; eye a httle in advance of the middle of the head, 1.5 in the
interorbital ; gill-opening not continued forward to below the eye; maxillary barbels
three-fifths the length of the head, not reaching the gill-opening; nasal barbels
extending to the eye; dorsal entirely in front of the anal; origin of dorsal midway
between snout and tip of caudal; caudal rounded. Pale browoi above, with three
longitudinal series of large squarish brown blotches. Fins immaculate, the largest
40 mm.

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 341

65. Pygidium santae-ritae sp. nov. (Plate LII, fig. 5.)
7599, C. M., type, 24 mm. Santa Rita, Rio Preto. July 10, 1908. Haseman.

Head 4; D.ll; A. about 9; P. 8; eye very nearly in the middle of the head;
about two in the snout, five in the head, a little less than interorbital; teeth pointed,
in a single series or in a very narrow band; gill-openings extending to below the
middle of the eye; nasal barbel extending but little beyond posterior nares; maxil-
lary barbels to middle of interopercle ; outer pectoral ray not prolonged, a little less
than head; origin of ventrals equidistant from snout and middle of caudal; anal
entirely behind the dorsal, distance between its last ray and the caudal 4.5 in the
length; caudal rounded, 5 in the length; distance between origin of dorsal and caudal
equal to distance between dorsal and the middle of the eye.

Sides with large spots.

In the length of the barbels and the color this species agrees very closely with
P. minutum from southern Rio Grande do Sul, with which it may be synonymous.
It differs in its longer head, the forward extent of the gill-opening, the more anterior
position of the dorsal. While the number of fin-rays as given differs, not much
weight attaches to this. I have endeavored to count all of the rudiments.

Genus V. Eremophilus^" Humboldt. (Plate XXXVI; Plate XL, figs. A, B.)

Eremophilus sive Thrichomycterus Humboldt, Rec. d'Obs. Zool. et Anat., I,
1805, p. 17, pi. 6, reprinted in 1912, title-page 1911.
Trachypojna Giebel, Zeitschr. Gesellsch. Naturw., Ill, 1871, p. 97 (type marmora-

tum = mutisii).

Type. — Eremophilus mutisii Humboldt.

Like Pygidium, but without ventrals.

1. Eremophilus mutisii Humboldt. (PI. XLI, figs. 1,2; PI. LIV, figs. 1, 2.)
Eremophilus tnutisii Humboldt, I. c, I, 1805, p. 17, pi. 6; Valenciennes, in Hum-
boldt, II, 1835, p. 340; Cuvier & Valenciennes, Hist. Nat. Poiss., XV, 1846,
p. 500, pi. 553 (Bogotd); Gijnther, Cat. Fishes Brit. Mus., V, 1864, p. 275;
EiGENMANN & EiGENMANN, Proc. Cal. Acad. Sci. (2), II, 1889, p. 53; Occa-
sional Papers Cal. Acad. Sci., I, 1890, p. 339; Proc. U. S. Nat. Mus., XIV,

'" *pi)M0(^tXij5, 6 = loving solitude (of the mountain lakes and streams).

" Je I'ai nomm6 irimophile, h. cause do la solitude dans laquelle il vit si de si grandes hauteurs, et
dans des caux qui nc sunt presque liabit6es par aucun autre ctrc vivant. Les naturalists qui craignent que
de nouvoUcs cspccos de ce nicmc genre nc viennent a etre d^'-couvertos dans des situations tr&s-difT(?rentes,
pourroient changer le nom d'Mmophile en celui de thrichomycterus, tir6 d^s barbiUons attaches au nez de
ce poisson."

342 MEMOIRS OF THE CARNEGIE MUSEUM.

1891, p. 37; EiGENMANN, Reports Princeton Univ. Exped. Patagonia, III,

1910, p. 400; Indiana University Studies, No. 23, Sept., 1914, p. 230.
Trachypoma marmomtum Giebel, /. c.

Habitat. — Plain of Bogota and north of it for a short distance.
5046o-7>, C. M.; 12840, I. U. M., many, largest 325 mm. Ponta de Suba, north of

C'hapinero. Eigenmann.
5049, C. M.,.two, largest 300 mm. Laguna near Bogota (bought in the market).

Eigenmann.
5048a-A;, C. M.; 12841, I. U. M., twenty-two, largest 210. Herrera. Eigenmann.
5047a-/t, C. M.; 12842, I. U. M., sixteen, largest 270 mm. Madrid. Eigenmann.
7445a, C. M.; 13834, I. U. M., two, 142 and 165 mm. Rio Chiquinquiere, Boyaca.

Gonzales.
7446o, C. M., one, 220 mm. Rio Bogota. Gonzales.
13836, I. U. M., three, 130-160 mm. Rio Funjuelo at Usme Sur near Bogota.

Head 5.33-6; depth 5-6.33; D. 11.5; A. 9.5; P. 8; head pointed, a httle longer
than wide; center of the eye very little in advance of the center of the head; inter-
ocular three times, or a little more, in the head; teeth conical, in three to five rows;
gill-ojienings not extending forward to below the eye; a very narrow free mem-
brane across the isthmus.

Nasal barbel extending to the base of the opercular spines or shorter; maxillary
barbel extending very little if anj'^ further than the nasal barbels; pectoral 1.5-2
in the head, its first ray sometimes very slightly produced, origin of anal about
under the middle of the dorsal, the distance between the last ray and the middle
caudal rays 4.5-5.5 in the length; depth of caudal peduncle 1.25-1.5 in its length,
.66-.8 in the greater depth; caudal very broad and short, its. length seven or more
in the length; origin of dorsal nearly equidistant from tip of caudal and the head,
its distance from the base of the middle caudal rays 1.8-2 in its distance from the
snout.

Blackish, everywhere with well-defined but irregular spots or vermiculations.
The black background most abundant above, the light vermiculations predominant
below. In some specimens the dark predominates everywhere, the light being
reduced to spots, or vermiculations, in others the light predominates; in the young
there is a narrow dark median stripe, and the dark of the caudal peduncle consists
of a few irregular spots, on the back in front of the dorsal the tj^pical color of the
adult obtains. Very variable.

The specimens from the Rio Funjuelo deserve special mention.

The largest measures a few millimeters over 160; it is not possible to give

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 343

the exact length, owing to the curves. This specimen is without pigment. The
eye is apparent only on account of the lens and its overlying hyaline skin. The
eye measures 2 mm. in diameter. This measurement is taken with the skin re-
moved. The eye is not i)igmented.

Another specimen measures 130 mm. It is also without pigment except in the
eye. The eye seems to be fully pigmented and measures about 2 mm.

The third specimen measures 133 mm. The caudal and all but a small patch
on the dorsal surface of the caudal peduncle are without pigment. The region
from the caudal peduncle to the head is pigmented, but much more sparingly than
in normal specimens, and there are irregular pigment-free spots. The sides of the
head behind the eyes are free from pigment, the dorsal surface of the head and
snout are again pigmented. The eye is normally pigmented and measures a little
less than 2 mm.

These specimens seem to be identical with the normal "Capitan" in all respects
except the color.

As stated elsewhere, the "Capitan" is a fish of considerable importance on the
plains of Bogota. The fish are caught with long-handled dip-nets several feet in
diameter. The net is held in a slanting position by one man, one or several others
drive the fishes into the net by beating the water. From time to time the net is
raised and the fish removed. We supplemented this method by having the Indians
drag a small seine, which yielded many smaller specimens. All we caught were
about 80 mm. long or longer, i. e., we caught no verj' j'oung ones. The Indians
also secured specimens bj^ thrusting their hands and arms into the holes in the banks.
It has heretofore been recorded exclusively from the Plains of Bogota. Mr. Gon-
zales has sent two specimens from the Rio Chiquinquiere north of the plain.

Genus VI. Pareiodon^i Kner. (Plate XXXVII.)
Pareiodon Kner, Sb. Ak. Wiss. Wien, XVII, 1855, p. 160.
Centrophorus Kner, Denkschr. Akad. Wiss. Wien, 1859, XVII, p. 167.
Astemomyderus Guichenot, Rev. et Mag. Nat. Hist., XII, 1860, p. 525, fig. 2

(pusillus) .
Pariodon GDnther, Cat. Fishes Brit. Mus., V, 1864, p. 275.

Type. — Pareiodon microps Kner.

No mental barbels, no nasal barbel, two slender barbels at angle of mouth;
outer pectoral ray not prolonged beyond the other rays; gill-membrane confluent
with the isthmus, without a free fold in the middle, a narrow fold just below the

" Trapda = cheek, (SJo6s, A = tooth.

344

MEMOIRS OF THE CARNEGIE MUSEUM.

gill-opcning which is restricted to the space behind the interopercular spines, the
membrane being confluent with the shoulder behind the opercular spines; mouth

subterminal, a single series of teeth in each jaw, about
sixteen on the pre-operclc and about thirteen on the
mandible. The teeth of the two jaws alike, similar to
the teeth at the end of the premaxillary of Branchioica and
some species of Vandellia. They consist of a narrow
basal section, an enlarged middle section, from the inner
(median) angle of which projects a short spur laterad, the
spur being shghtly twisted from the plane of the rest of
the tooth; the teeth not movable; interopercle with a
single scries of six backward directed, slightly divergent
spines; opercular spines slightly divergent, four spines
in the main posterior row; five much smaller ones in
the anterior row; caudal forked.

Pareiodon has the appearance of an overgrown Van-
dellia, from which it differs in dentition, in the size of the
eye, and the general shape of the head.

Fig. 21. Pnrciudon microp^
Kiier. a, outline of head from
above; 6, the interopercular
spines; c, the opercular spines;
(/, a premaxillary and a man-
diliular tootli, very much en-
larged.

1. Pareiodon microps Kner. (Plate LIV, fig. 3.)

Pareiodon microps Kner, I. c. (Borba on the Madeira about four days from its
mouth); Eigenmann & Eigenmann, Proc. Cal. Acad. Sci. (2), II, 1889,
p. 55; Occasional Papers Cal. Acad. Sci., I, 1890, p. 346; Proc. U. S. Nat. Mus.,
XIV, 1891, p. 37; Ribeiro, Fauna Bras., IV (A), 1912, p. 232; Comm. Linhas
Telegraphicas Estrategicas de Matto-Grosso ao Amazonas. Annexo 5, Sept.,
1912, p. 30 (Manaos) ; Fowler, Proc. Acad. Nat. Sci. Phila., 1915, 229 (Amazon
between mouth of Rio Negro and Peru).

Pariodon microps Gunther, Cat. Fishes Brit. Mus., V, 1864, p. 275; Cope, Proc.
Acad. Nat. Sci. Phila., 1872, 290 (between Rio Negro and Peru.)

Trichomycterus pvsillus Castelnau, Anim. Amcr. du Sud, Poissons, 1855, p. 50,
pi. 24, fig. 4 (Araguay; Amazon).

Aslemomycierus pvsillus Guichenot, I. c. (Araguay; Amazon).

Pareiodon pusillus Ribeiro, I. c, p. 234.
Habitat. ^Amazon Basin.
The specimen in the collection of the Philadelphia Academy of Sciences,

mentioned by Cope and Fowler, is about 145 mm. long. I am indebted to Dr.

Fowler for the loan of this specimen.

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 345

Head 8; depth 6; D. 10, of which eight are full length; A. 7, of which five are
full length; ej'e minute, about thirteen times in the head; center of head a full
orbital diameter behind the posterior margin of the eye; interorbital 2.1 in the
length of the head, snout 3 in the head, broad; width of head equal to its length;
maxillary barbel not reaching to the intcropercular spines; lower barbel reaching a
little beyond the middle of the maxillary barbel ; depth of caudal peduncle two and
one-fourth in its length; pectoral about equal to the length of the head without the
opercle; distance between origin of dorsal and base of caudal twice its distance from
the snout; last dorsal ray slightly in front of the anal; dorsal and anal truncate or
slightly emarginate; anus under middle of dorsal; ventrals not reaching anus, their
origin equidistant from tip of caudal and interopercle ; caudal deeply forked, the
upper lobe two and one-half times as long as the middle rays; caudal fulcra not
conspicuous.

Genus VII. Henonemus''- Eigenmann & Ward. (Plate XXXVI).
Henonemus Eigenmann & Ward, Ann. Carnegie Mus., IV, 1907, p. 118 {inter-

medius) .
Cobitiglanis Fowler, Proc. Acad. Nat. Sci. Phila., 1914, p. 268, fig. 16 {taxistigma) .

Type. — Stegophilus intermedius Eigenmann & Eigenmann.

The genus Henonemus was created for Stegophilus intermedius on the obser-
vation that it has but one barbel at the angle of the mouth. The second (lower)
barbel at the angle of the mouth is so minute that it ought not to be considered of
generic value, especially since a minute barbel has been found on closer observation
in a number of cases where but one barbel had been recorded. It is probably present
in the type of Henonemus. The types of Homodicetus and Henonemus differ in the
number of opercular spines, four or five in the former, but two in the latter. The
names may, therefore, be at least temporarily retained.

Cobitiglanis was proposed as a subgenus of Oehmacanthus. How'ever, the type
of Cobitiglanis is not related to Oehmacanthus. Cobitiglanis taxistigtna is scarcely
distinct from H. punctatus and the name Colf(itiganis is a synonym of the subgenus cr«i«TA
Henonemus.

This genus, as far as known, consists of free-living species, and is closely re-
lated to the commensal Stegophilus. The mouth is wide, inferior, provided with
numerous teeth in series on the jaws and lijis; those of the middle of the upper lip
are long and in part are homologous with those of Vandellia; the opercle bears two
spines, the pre-opercle five or more. Where observed, the lower barbel is very
minute, followed by an additional barbel or labial lobe ; the lower jaw is well formed,

'■- ill = one, ytjita = thread. A niisnonier, since there are two maxillary barbels.

346 MEMOIRS OF THE CARNEGIE MUSEUM.

the rami transverse, united. The genus differs from Stcgopliilas chiefly in the shape
of the caudal, which is emarginate instead of rounded, and in the number of oper-
cular spines.

Key to the Species of Henonemds.

a. Origin of dorsal oquidistant from tip of caudal and interopercle; origin of vcntrals nearly pquidistant
from tip of lower caudal lobe and snout.
6. Sides plain, caudal spotted, last half of its lower lobo black; D. 10; A. 9.

1. macrops (Steindachner).
hb. Sides with a median scries of spots, and smaller spots above them; tip <if lower caudal lobe and

an oblique band across the upper lobe black 2. punctatus (Boulenger).

hbb. Sides with a regular series of spots, smaller sp(jts abnve them; lower caudal lobe nt)t black at tip,

several obscure spots on dorsal, caudal and base of pectoral 3. taxistigmus (Fowler).

aa. Origin of dorsal equidistant from tip of caudal and occiput; origin of ventrals equidistant from bases
of caudal and pectoral; caudal with faint dusky spots; upper surface with dark spots; a series of
larger spots along the middle of the sides 4. intermedius (Eigeumann & Eigenmann).

1. Henonemus macrops (Steindachner).
Stegophilus macrops Steindachner, Flussf. Hiidam., IV, 1882, p. 28, pi. VI, fig.

2-2a (Lake Manacapuru) ; Eigenmann & Eigenmann, Proc. Cal. Acad. Sci.

(2), II, 1889, p. 55; Occasional Papers (^al. Acad. Sci., I, 1890, p. 344; Proc.

U. S. Nat. IMus., XIV, 1891, p. 37.
Henonemus macrops Eigenmann, Reports Princeton Univ. Exped. Patagonia, III,

1910, p. 401; Ribeiro, Fauna Bras., IV {A), 1912, p. 231.

Habitat. — Lake Manacajnuii .

Fig. 22. Henoncmvs macrops Steindachner. (After Steindachner.)

Known from the types only, which arc in the Vienna Museum. Head 5;
depth 5; D. 10; A. 9; P. 6; eye 3.4 in the head; width of head 1.25 in its length;
barbel scarcely more than half as long as the eye; pectoral equals the head without
the snout; distance between caudal and origin of dorsal 1.5 in its distance from the
snout; origin of anal under the last dorsal ray; sides of head and body without spots;
tip of lower caudal lobe dark, the other fins plain.

2. Henonemus punctatus (Boulenger). (Plate XL, fig. C.)
Stegophihis punctatus (Boulenger), Proc. Zool. Soc. Lond., 1887, p. 279, pi. XXI,
fig. 4 (C'anelos); Eigenmann & Eigenmann, Proc. Cal. Acad. Sci. (2), II,

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 347

1889, p. 54; Occasional Papers Cal. Acad. Sci., I, 1890, p. 343; Proc. U. S. Nat.

Mus., XIV, 1891, p. 37.
Henonemus pundatus Eigenmann, Reports Princeton Univ. Exped. Patagonia,

III, 1910, p. 401.

Habitat. — Canelos, Ecuador; Santarem, Brazil.

Mr. Haseman collected the following specimens:
7083, C. M., fourteen, largest 88 mm. Santarem, Dec. 9, 1909.
7544, C. M., four, 72-90 mm. San Antonio, Rio Madeira, Nov. 3, 1909.

Fig. 23. Henonemus piinclntun (Boulcnger). After Boulcnger.

Head 5.5-6; depth 6.5-7; D. 10 or 11; A. 8; P. 6; eye 4 in the head; width of
the head 1.2 in its length; opercle with two spines, interopercle with four in the
main row, of which the upper is much larger, two in the second row; three rows of
movable teeth in the lip of the uj^per jaw, the rows close together, the teeth minute,

Fio. 24. Henonemus pundatus (Steindachncr). .1, opercle with its two spines; B, pre-opercle
with its spines; C, half of the preinaxillary with its teeth.

348 MEMOIRS OF THE CARNEGIE MUSEUM.

except for tlie middle ones of the inner series, which are much larger, similar to those
in the premaxillary of VaudcUia; four rows on the premaxillarj', of which the three
outer rows are similar to, but a little larger than, the labial teeth; the teeth of the
inner series are pressed together, broad, bent toward the middle line near the tip and
then are abruptly bent backward and inward, then outward; about fifty teeth in
the inner row on each side, about seventy-five in the next row; five rows of teeth
in the lower jaw, the outer scries labial, those of the next three rows minute, re-
curved hooks, those of the innermost series like those of the inner series of the
uj^per jaw; eye large, without a free orbital rim; posterior nares in a line with the
anterior margin of the eye, much closer together than the anterior; no nasal barbel;
maxillary barbel broad at base entirely concealing the very minute second barbel.
Axillary gland large, the pectorals considerably shorter than the head; distance
of origin of dorsal from caudal 1.5-1.75 in its distance from the snout; origin of anal
under or behind the last dorsal ray; back with numerous small spots; sides with a
row of much larger spots; lower caudal lobe dark toward tip, base of the fin spotted
like the sides, upper lobe free from chromatophores toward its tip, a few spots along
lower margin of caudal peduncle; dorsal with spots on its basal half.

3. Henonemus taxistigmus (Fowler).
Ochmacanthus (Cobitoglanis) taxistigma Fowler, Proc. Acad. Nat. Sci. Phila., 1914,

p. 268 {Rupununi'RiYev) .

Habitat. — Rupununi River, British Guiana.

Known from the type, 39344 A. N. S. P., 93 mm., which I have had the oppor-
tunity to examine through the courtesy of Dr. H. W. Fowler.

Head 5.5; depth 6.5; D. 10; A. 7.5; P. 7; eye 3-3.33 in the head, width of head
1.1, snout 3.25, width of mouth 1.5, interorbital 3.5, pectoral 1.4, lower caudal lobe
1.17, caudal peduncle 2.5; lower barbel one-fifth as long as the upper; upper jaw
with four series of teeth, upper Hp with three, at least seven series in the mandible;
pre-opercle with five or more spines; opercle with two smaller spines; origin of
dorsal equidistant from tip of caudal and interopercle.

»'■•'■:•■ ■■■" ;■■,.■".»' > « .

Fig. 25. Henonemus taxistigmus (Fowler). After Fowler.

Predorsal region with about four series of irregular, dusky spots, upper surface

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 349

of head with similar spots, one marking the interopercular, another the opercular
spines; a few median, dusky spots behind the dorsal; sixteen sharply defined, dusky
blotches along the lateral line increasing in size to the caudal peduncle. Fins all
pale or whitish, several obscure spots of dusky on dorsal, caudal, and base of pec-
toral.

4. Henonemus intermedius (Eigenmann & Eigenmann).
Stegophilus intermedius Eigenmann & Eigenmann, Proc. Cal. Acad. Sci. (2), II,

1889, p. 54; Occasional Papers Cal. Acad. Sci., I, 1890, p. 343; Proc. U. S. Nat.

Mus., XIV, 1891, p. 37.
Henonemus intermedius Eigenmann, Reports Princeton Univ. Exped. Patagonia,

III, 1910, p. 401; Ribeiro, Fauna Bras., IV {A), 1912, p. 230.

//a6i7ai.-^Headwaters of the Rio Araguay.

This species, found in a region intermediate between the locahties where
punctatus and maculatus are found, combines in a remarkable way the characters
of those species.

Type, No. 9842, M. C. Z., one specimen, 80 mm. Goj^az. Senhor Honorio.

Head 5.5; D. 9; A. 7; eye equals snout, 3.5 in the head; mouth large, upper lip
with two series of teeth, premaxillary and mandible with four series of deprcssible
teeth, those of the inner series enlarged at the tip; barbel shorter than eye; head a
little longer than wide; opercle with two spines, interopercle with five or six claw-
like spines

Elongate, compressed behind, depressed forward; head somewhat longer than
wide, snout pointed; eye large, once in the snout, three and one-half times in the
head. Mouth large. Lower lip not dilated. Origin of dorsal about equidistant
from tip of caudal and occiput; caudal emarginate; anal placed entirelj^ behind the
dorsal; origin of ventrals equidistant from bases of caudal and pectoral. Light
brown; entire upper surface with rather large dark brown spots; a series of larger
dark spots along the middle line of the sides, the spots becoming larger towards
the tail; caudal with a few, faint, dark spots.

Genus VIII. Pseudostegophilus'^ Eigenmann & Eigenmann.
Pseudostegophilus Eigenmann & Eigenmann, Proc. Cal. Acad. Sci. (2), II, 1889,

p. 54.
Type. — Stegophilus nemurus Gunther.

This genus has the characters of Homodicetus but has a deeply forked caudal.

'' ^€u5ijs = false; Stegophilus, the name of a related genus, see p. 353, from aTiym, t4 = a roof, and
<^(Xos, A = a lover.

350 MEMOIRS OF THE CARNEGIE MUSEUM.

1. Pseudostegophilus nemurus (Giinther). (Plate XLIV, fig. 5.)

Stegophilus nemwus Gunther, Proc. Zool. Soc, London, 1869, p. 429. (Peruvian

Amazon.)
PseudostegopMlus nemurus Eigenmann & Eigenmann, Proc. Cal. Acad. Sci. (2),

II, 1889, p. 54 (Maranon or Ucaj'ale); Occasional Papers Cal. Acad., Sci. I,

1890, p. 341; Proc. U. S. Nat. Mus., XIV, 1891, p. 37; Eigenmann, Reports

Princeton Univ. Exped. Patagonia, III, 1910, p. 400.

Habitat. — Upper Amazon, Rio Mamore.
7547a-/, C. M., 63-78 mm. Rio Mamore. Sept. 19, 1909. J. D. Haseman.

Head 5; depth 6-6.5; D. 9; A. 7; P. 6; eye 4-4.5 in the head, less than snout or
interorbital; maxillary barbel about as long as the eye, lower barbel very minute.
Five rows of teeth on the ui:)i)cr lip, four in the upper jaw, six rows in the lower jaw
and Hp; gill-membrane not forming a fold across the isthmus; eight or nine spines
on the intcropercle and opercle; pectoral a little shorter than the head; origin of
ventrals about equidistant from tip of snout and tip of middle caudal ray (its base
in a specimen in the Mus. Comp. Zool.) ; origin of anal behind the dorsal, the dis-
tance of the base of its last ray from the base of the middle caudal ray four and one-
half in the length; caudal deeply forked, the lobes pointed, the upper lobe longer
than the lower; distance of origin of dorsal from base of middle caudal rays 1.5-1.6
in its distance from the snout; a dark shade across the head between the eyes,
another between the opercles, four bands across the back and sides about equal to
the interspaces, the margins of the bands darkest; lower caudal lobe and tip of the
upper black.

Genus IX. Homodi^tus^'' Eigenmann & Ward. (Plate XXXVII.)

Hojiiodioetus Eigenmann & Ward, Annals Carnegie Mus., IV, 1907, p. 117, pi.
XXXIV, figs. 2 and 3 {anisitsi).
Type. — Honiodicetus anisitsi Eigenmann & Ward.

Opercle with four or five spines directed upward and backward, interopercle
with more, directed downward and backward; c,ye 3.5-5 in the head. Otherwise
like Henonemus.

Key to the Species of Homodi.etus.
a. Caudal slightly emarginato, oblique; accessory rays numerous; origin of dorsal equidistant, from tip of
caudal and eye; origin of ventrals equidistant from snout and caudal; D. 8; A. 8; back and sides
with chromatophores, but without distinct spots; middle caudal rays black.

1. anisitsi Eigenmann & Ward.

" biioSimm = living or eating with others. In allusion to the known parasitic habits of some of its
relatives.

EIGENMANN: the PYf;iDIID.E, A FAMILY OF SOUTH AMERICAN CATFISHES. 351

aa. Caudal forked or deeply eniarginate, accessory rays few, inconspicuous; origin of dorsal a little nearer
tip of snout than tip of upper caudal lobe, or the reverse; origin of ventrals cciuidistant from base of
caudal and the eye, or a little nearer the former; D. 10; A. 7; buck and sides with conspicuous spots
unsymmetrically distributed, sometimes in part arranged as a median series; a spot at base of
caudal, tips of caudal lobes black 2. maculatus (Steindachner).

1. Homodiaetus anisitsi Eigcnmann & Ward. (Plate LVI, figs. 3 and 5.)'^
Homodioetus anisitsi Eigenmann & Ward, Ann. Carnegie Mus., IV, 1907, p. 117,

pi. XXXIV, figs. 2 and 3 (Villa Rica); Eigenmann, Reports Princeton Univ.

Exped. Patagonia, III, 1910, p. 401.

Habitat. — Villa Rica, Paraguay.

Known only from the type in the collection of Indiana University.
10155, I. U. M., 9 , 43 mm., the type. Small creek at Villa Rica, Paraguay.

Anisits.

Head 6.5; depth 5.75; D. 8; A. 8; eye ccjuals snout, 3.5 in the head, about equal
to interorbital; head nearly as wide as long; opercle with about four spines, inter-
opercle with six; the barbel shorter than the eye, the inner barbels much smaller;
upper jaw and lips each with about four distinct series of teeth; those on the hps
freely movable; the teeth narrow, more or less spoon-oar-shaped, those of the inner
series slightly larger; lower lip without teeth, three series of teeth on the jaw.

Axillary gland very large ; origin of dorsal equidistant from tip of caudal and
posterior margin of the eye; caudal slightly cmarginatc, the upper lobe longest;
origin of anal under end of dorsal; ventrals reaching vent, which is equidistant from
tip of mouth and tip of caudal, origin of ventrals equidistant from snout and caudal.
Accessory rays numerous.

In alcohol uniformly pale. The fresh specimen preserved in formalin was straw-
colored, the back with numerous large, conspicuous, stellate, black chromatophorcs,
and many more smaller, much less conspicuous, brown ones; sides with a few small,
stellate, black, chromatophorcs, gradually giving rise to a regular series along the
middle of the tail; a dusky streak along the sides between the myotomes of the body
and the thin covering of the abdominal cavity; a small, black spot at the base of
the middle caudal ray; middle caudal rays dark, becoming intensely black toward
tip; obli(iue bars extending from the end of the second ray below median dark one
downward and forward to the tip of the lower caudal fulcra and then as a black line
forward along the tips of the fulcra; another one like it in all respects from the tip
of the second ray above the median dark one upward and forward to the tip of the
caudal fulcra and then forward along their tips as a black line; remaining fins more
or less dotted.

" The caudal should be emarginate in the figure.

352 MEMOIRS OF THE CARNEGIE MUSEUM.

Alimentarj' canal straight, without convolutions or bends, the thin-walled
stomach lying lengthwise and giving rise to a short, thin intestine, which merges
into the much longer and larger, but thin-walled, large intestine which appears to
be filled with minute grains of sand.

2. Homodiaetus maculatus (Stcindachner).
Stegophilus maculatus Steindachner, Denk. Ak. Wiss., Wien, XLI, 1879, p. 25,
IV, fig. 2 (La Plata); Eigenmann & Eigenmann, Proc. Cal. Acad.- Sci. (2),

II, 1889, p. 54; Occasional Papers Cal. Acad. Sci., I, 1890, p. 343; Proc. U. S.
Nat. Mus., XIV, 1891, p. 37.

Henonemus maculatus Eigenmann, Reports Princeton Univ. Exped. Patagonia,

III, 1910, p. 401.

Habitat. — La Plata, in Province Buenos Aires; Uruguay Basin.

Known from the type, a specimen 105 mm. long, and
7545a-(i, (J. M., 67-69 mm. Uruguayana, Feb. 6, 1907. J. D. Hascman.
7546a-c, C. M., 64-70 mm. Cacequy. Feb. 2, 1907. J. D. Haseman.

Head 5.75-6.75; depth 6-9; D. 9; A. 7; P. 6; eye 3.66-4 in head, equal to snout
or interorbital ; maxillary barbel filamentous, equal to the eye, the inner barbel
much smaller; seven series of teeth in the upper jaw and lip, five in the lower; about
seven, graduate, opercular spines, about nine larger interopercular spines; gill-
membrane forming a free fold across the isthmus; anal behind the dorsal. In the
type, a series of spots along the back, another row of spots along the middle of the
sides; two or three rows of smaller spots between the two; base of caudal with a
dark cross-bar, several small spots along the upper edge of the caudal; tips of the
caudal dark spotted.

Fig. 26. Homuiliutus maculatus (Steindachner). After Steindachner.

EIGENMANN: the PYGIDIIDvE, a family of south AMERICAN CATFISHES. 353

In the specimens collected by Haseman the color-marking is less regular, the
sides and back with unsymmetrically placed spots, largest on the caudal peduncle,
smallest on top of the head, sometimes arranged in a series along the middle of the
sides; the spot at the base of the caudal largely above the middle.

Genus X. Stegophilus^« Reinhardt. (Plate XXXVII.)
Stegophilus Reinhardt, Vidensk. Meddel. Naturh. Foren., Kjobenhavn., 1858

(1859), p. 79, pi. II.

Type. — Stegophilus insidiosus Reinhardt.

No nasal or mental barbel, lower barbel at angle of mouth excessively minute,
a minute dermal flap below the lower barbel; mouth very wide, inferior; eye large,
superior; posterior nares between the front parts of the eyes; opercle and inter-
opercle with several spines; gill-opening narrow, about a third as wide as the mouth,
in front of the pectoral, the membrane not forming a free margin; first pectoral ray
not produced in a filament; origin of ventral one and a half to two times as far from
snout as from caudal; caudal rounded, not greatly contracted at base, the accessory
rays not conspicuous; origin of dorsal behind the vertical from the origin of the
ventrals; teeth very numerous, in regular series, those in the middle of the upper
jaw larger than the others.

1. Stegophilus insidiosus Reinhardt.
Stegophilus insidiosus Reinhardt, I. c, p. 79-97; Gijnther, Cat. Fishes Brit. Mus.,

V, 1864, p. 276; Lutken, Velhas Flodens Fiske, p. 15; Vidensk. Selsk. Skr.

(5), Afd. XII, 1875, p. 135, and I, text figures 1-3 (Rio das Velhas) ; Eigenmann

& Eigenmann, Proc. Cal. Acad. Sci. (2), II, 1889, p. 55; Occasional Papers

Cal. Acad. Sci., I, 1890, p. 344; Proc. U. S. Nat. Mus., XIV, 1891, p. 37;

Eigenmann, Reports Princeton Univ. Exped. Patagonia, III, 1910, p. 400.

Habitat. — Parasitic in large fishes (Pseudoplatystoma orbignianum = coruscans)
of the San Francisco basin and free on sand bars of the upper San Francisco basin.
7551, C. M., one, 32 mm. Opposite Januaria. Doc. 12, 1907. Haseman.

This example is the first one secured since Reinhardt obtained his specimens
from the gill-chamber of a large catfish, Pseudoplatystoma. Ha.seman took his
specimen on Dec. 12, 1907, from the sandy shore of an island in the Rio San Fran-
cisco, in front of the town of Januaria. If this specimen is really identical with
those secured by Reinhardt from the same river basin, Stegophilus appears to have
the general habit of members of the family of burrowing in .sand as well as the pecu-
liar habit of entering the gill-chambers of other fishes. This double, Jekyl and

"oTi705, t6 = a, roof; <t>l\ot, o = a lover, t. e., loving a covered home, in allusion to its habit of living
in the gill-cavities of other fishes.

354

MEMOIRS OF THE CARNEGIE MUSEUM.

Hyde, habit of Stegophilus lends probability to tlie reported habit of Vandellia
of entering the urcthrse of bathers. For an account of the habit of the species
see page 267.

Fk!. 27. Stcgophihis insidiosuy liciiiliaidt. (After Liitken.)

Head about six times in the length; D. 8; A. 7; P. 7; eye about equal to snout
or intcrorbital, four times in the head; maxillary barbel equal to half the width of
the mouth, extending to the interopercular spines, lower barbel about four-tenths
as long; a thin, narrow membranous flap below the lower barbel; head flat below,
its width equal to its length less the opercular spines.

This specimen has hardened in the alcohol and it is not possible to describe
the details of the teeth.

Ten or eleven hooks in two series, on the interopercle, directed downward and
backward, eleven or twelve thorns on the opercle in three or four irregular series,
increasing in size from the minute anterior ones to the strong posterior one.

Pectoral about as long as the head without the snout; origin of ventrals equi-
distant from base of caudal and tip of pectoral; distance between origin of dorsal
and base of middle caudal rays 2.33 in its distance from the snout, distance between
last anal ray and base of caudal 6.5 in the length; caudal rounded, ventral accessory
rays inconspicuous, a few prominent dorsal accessory rays.

No color-markings.

Genus XI. Acanthopoma" Lutken. (Plate XXXVH.)
Acanthopoma LDtken, Vidensk. Meddel. Naturh. Foren. Kjobenhavn, for 1891,
1892, p. 53, fig. (cmnectens).

Like Stegophilus, the gill-membranes forming a free fold across the isthmus.
" oKocffos, 6 = spine; wuiia, t6 = opercle.

EIGENMANN: the PYGIDIID/E, a family of south AMERICAN CATFISHES. 355

1. Acanthopoma annectens Liitken.

Acanthopoma annectens Lutken, /. c. (Huallaga); Eigenmann, Ann. Carnegie Mus.,
IV, 1907, p. 119; Reports Princeton Univ. Exped. Patagonia, III, 1910, p. 401.
Habitat. — Huallaga.

Known from the type 100 mm. long in the collection of Prof. R. I^euckart.
Anterior part, especially the head, depressed; head parabolic; eyes not large; dis-
tance between anterior nare.s twice the distance between the posterior, neither with
a barbel; a group of four to six large and some small spines on the opercle; another
larger group, ten to twelve, on the interopercle ; mouth inferior; upper jaw with six
to seven very regular rows of very small teeth; in the lower jaw are "naeppe mere
end en enkelt Roekke telstede." Free margin of the gill-membrane begins behind
the interopercle and is continued across the isthmus without uniting with it.

Fig. 28. Acanthopoma annectens Lutken. (After Lutken.)

Origin of ventrals equidistant from bases of caudal and pectoral, or tip of
caudal and the mouth; origin of dorsal nearly twice as far from snout as from base
of caudal; origin of anal under end of dorsal; caudal slightly emarginate; back with
obscure spots.

Called annectens to indicate its supposed position between the Pygidiina; and
StegophiliniC.

Lutken saj's it is nearest Henonemus microps = macrops?

Genus XII. Ochmacanthus'^ Eigenmann. (Plate XXX\'II.)

Ochmacanthus Eigenmann, Mem. Cam. Mus., V, June, 1912, p. 213.

Gyrinurus Ribeiro, Comm. Linhas Telegraphicas Estrategicas de Matto-Grosso

ao Amazonas, Annexo No. 5, Sept., 1912, p. 27, pi. with three figures.

Type. — Ochmacanthus flabelliferus Eigenmann.

"* 8x/««i ri = a hold; iKca^m, 6 = 3, spine.

356 MEMOIRS OF THE CARNEGIE MUSEUM.

No nasal or mental barbels; lower barbel at angle of mouth minute or well
developed; mouth very wide, inferior; eye large, superior; posterior nares between
the anterior margins of the eyes; gill-opening verj^ small; first pectoral ray not
spinous, not produced in a filament; accessory caudal rays very numerous, the
caudal greatly contracted at base; origin of anal behind that of the dorsal; teeth
very numerous, in regular series, none on the lip of the upiicr jaw.

Key to the Species of Ochmacanthus.
a. Maxilhiry baibcl reaching pectoral; origin of dorsal equidistant between tip of caudal and snout or
nearer caudal; accessory caudal rays highest near the middle; distance between last anal ray and

caudal two in its distance from tiie snout. {Gi/rinurus) 1. batrachostoma (Ribeiro).

(in. Maxillary barbel about as long as the eye, reaching tip of intcropcrcular sjiines; origin of dorsal much

nearer tij) of caudal than snout; accessory caudal rays graduate to the caudal into which they

gradually merge. (Ochmncanlhun).

b. Distance between last anal ray and caudal 4-4.5 in the length; origin of dorsal in advance of

origin of anal; ventral.s not reaching anal; gill-opening extending from the opercle to behind the

middle or lower part of the opercular spines 2. reinhardti (Steindachner).

bb. Distance between last anal ray and caudal three in its distance from the snout; origin of dorsal
over origin of anal, ventrals reaching anal; gill-openings confined to the region between the
interopercular and opercular spines 3. flabelliferus Eigenmann.

1. Ochmacanthus batrachostoma (Ribeiro). (Plate LV, figs. 1-3.)

Gyrinurus batrachostoma Ribeiro, I. c. (S. Luiz de Caceres.)
Habitat. — Upper Paraguay.
Known from the type, a specimen 32 mm. long, and

7553, C'. M., about 31 mm. Puerto Suarcz, swampy shore of big bay between
Brazil and Bolivia. May 7, 1909. Haseman.

7554, C M., 30 mm. Rio Jaurii, twenty-eight miles above its mouth at Campos
Alegre, thirty miles southwest of Caceres. June 2, 1909. Haseman.

Head 5.5-6.5; depth 6.5-9; D. 10-12; A. 8-9; P. 4; eyes superio-lateral, three
or four in the head, longer than the snout, about equal to the interorbital ; maxillary
barbel reaching axil of pectoral, the lower one to the opercular spines; head as
broad as long; six to eight opercular spines arranged in a group; interopercle with
about five to eight spines in one or two series; teeth conical, in three parallel series;
body depressed in front, compres.sed behind; dorsal and anal rounded; dorsal
behind the ventrals, its origin equidistant from tip of snout and tip of caudal in the
figure of the type, its distance from the caudal 1.3-1.5 in its distance from the snout
in the specimens enumerated above; anal partly under dorsal, distance of its last
ray from the caudal about 3.5 in its distance from the caudal in the specimens at
hand; caudal minute, rounded, hidden in the accessory rays which are greatly

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 357

developed into fins like those of a larval frog; everywhere except on the belly spotted.
Twenty-one vertebrae behind the anal.
The type was caught among water-weeds {Eichomea azurea).

2. Ochmacanthus reinhardti (Steindachner). (Plate LV, fig. 4.)
Stegophilus reinhanlli Steindachner, Flussf. Si'idam., IV, 1882, p. 28, pi. VI, fig. 1

(Lake Manacapuru; Rio Iga; Montalegre; Tc^e; Tabatinga); Eigenmann &

EiGENMANN, Proc. Cal. Acad. Sci. (2), II, 1889, p. 55; Occasional Papers Cal.

Acad. Sci., 1, 1890, p. 344;Proc. U. S. Nat. Mus., XIV, 1891, p. 37; Eigenmann,

Reports Princeton Univ. Exped. Patagonia, III, 1910, p. 401; Ribeiro, Faima

Bras., IV {A), 1912, p. 401.

Habitat. — Amazons.
7552, C. M., 38 mm. Amazon, at upper end of island four miles above Santarem.

Dec. 9, 1909. Haseman.
7555a-6, C. M., 35-46 mm. Igarape de Jaura, entering R. Tapajos two miles

above Santarem. Dec. 11, 1909. Haseman.

Head 7; D. 11-13 (9 or 10 developed rays); A. 10-11 (8 or 9); P. 6, partly
adnate; eye equals snout, less than interorbital, entirelj^ in the anterior half of the
head, 4-5 in the head; maxillary barbel reaching interopercular spines, the lower
barbel a third or fourth as long; 8 or 9 interopercular spines, 9 to 12 opercular;
width of head equal to its length. Three series of teeth in the upper jaw, those of
the inner series close set, much more numerous than those of the outer series, the
teeth of the outer two series at the middle of the mouth a httle longer and more
slender than the rest; lower jaw with two comjijlcte scries of teeth, the inner series
similar to inner series of the upper jaw, those of the outer series larger, fewer, and
much more movable than those of the inner, about fifteen in the outer series, about
forty in the inner; four increasingly shorter series from the inner series outward
near the middle of the jaw.

A prominent pectoral pore, pectoral equal to the head or to the head without
the snout. Origin of ventrals equidistant from bases of caudal and pectoral or a
little farther forward, distance between last anal ray and caudal 4-4.5 in the length;
distance between origin of dorsal and base of caudal 1.75-2 in its distance from the
snout; caudal rounded, with many prominent accessory rays.

Back gray, sides and fins mottled.

3. Ochmacanthus fiabelliferus Eigenmann. (Plate LV, fig. 5.)
Ochmncanthus Jlahcllijerus Eigenmann, Mem. Carnegie Mus., V, 1912, p. 213.

Habitat. — Essequibo basin.

358 MEMOIRS OF THE CARNEGIE MUSEUM.

1729, C. M. ; 121 1 1 , 1. U. M., type and paratypcs, three, 33-35 mm. (Konawaruk.)
Head 5.33; dei)th 7; D. 8; A. 7; eye 1 in snout, 3.75 in head, 1 in space between
the eyes. Width of head equal to its length ; snout semicircular in outline, the head
depressed; mouth very wide, its width cciual to the length of the head less half the
snout; upiier jaw with three series of teeth; teeth of the two outer series conical,
those of the inner series broad, removed from the others, forming a solid palisade;
no labial teeth; lower jaw with an outer series of long, curved, claw-like teeth ih the
lip, and four series in the jaw, of which the first is short, near the middle, the second
extends farther to the sides, the third is longest, extending from the middle to the
side of the jaw, the fourth is shorter again and confined to the sides, not reaching
the median line of the jaw. Interopercle with nine claw-like erectile spines; opercle
somewhat prolonged, carrying a bunch of nine spines similar to those of the pre-
opercle above and behind the gill-opening. Gill-opening small, entirely above the
level of the middle of the pectoral; outer maxillary barbel about as long as the eye,
the inner one minute. Pectorals partly adnate; ventrals small, free, reaching anal;
dorsal about equal to the anal and but slightly farther forward.

''Light, with numerous chromatophores more or less aggregated in places; a
black spot on base of caudal."

The only specimens known were killed with hiari poison in a small ]:)ool of
back-water from the Essequibo.

Genus XII. Vandellia^'^ Cuvier & Valenciennes. (Plate XXXVIII.)

Genus XIII. Urinophilus Eigenmann.

Vanddlia Cuvier & Valenciennes, Hist. Nat. Poiss., XVIII, 184G, p. 386, pi.

547.

Tyyc of Vanddlia. — Vanddlia cirrhosa Cuvier & Valenciennes.

Long, slender fishes with small inferior mouth; a few teeth in a single series in
the middle of the upper jaw ; peculiar, claw-like teeth on the end of the maxillary
in some species, probably all of them; teeth on the mandible in some species, none
in other species; the mandibular rami not meeting, separated by a wide membrane;
opercular spines directed obliquely upward and backward, interopercular spines
directed downward and backward; gill-opening small; no nasal or mental barbels,
the lower of the barbels at angle of mouth very minute ; first pectoral ray not pro-
longed in a filament; ventrals very much nearer to caudal than to tip of snout; origin
of the anal behind that of the dorsal.

'" In honor of Domingo Vandelli, professor of natural history at Lisbon, who sent the types of the
genus to Lac^pSde.

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 359

There are two generic types contained in the genus as here understood. One
of the two genera has teeth on the mandibles and is represented by V. sanguinea
at least; the other genus lacks teeth in the mandible, and plazai and hasertmni at
least belong to this genus. I do not know whether the type of Vandellia belongs
to the one or the other of the genera. The new one may be named Urinophilus.
The type is to be selected after the structure of the mandible in Vandellia cirrhosa,
the type of Vandellia, has been examined.

The dentition of the Vandelliina; is very peculiar. There are one or two series
or a patch of pointed teeth in the center of the upper jaw. They are immediately
below the center of the ethmoid at its anterior end, in other words, in the region
occupied by the premaxillary in related forms. The bones are so thin and the fish so
small, that it is difficult to determine all of the outfines of the bones, or to determine
the identity of all of the bones. The bone on which these teeth are inserted is, in
all probability, the premaxillarj'. The lateral points of the ethmoid are forked, and
dovetail into the forked ends of maxillaries somewhat after the fashion of the two
hands locked into each other between the thumbs and fingers. On the distal half
of the maxillary of Vandellia there are from two to four comparatively large and
very peculiar "claw-teeth," arranged like overlapi)ing shingles, the outermost one
being next the bone, the second from the end overlapping this and so on to the
proximal one. The individual teeth consist of a flat, oval disk, from the upper
proximal corner of which the tooth proper points toward the end of the bone. The
bone touches the palatines proximally and the maxillary barbel is joined rather
firmly to the end of it, all of which indicates that this bone is the maxillary. In
Branchioica only one or two teeth of this sort are present, but between them and
the ethmoid there is a series of slender, pointed teeth, similar to those on the pre-
maxillary.

Catfishes with teeth on the maxillaries are very unusual. Outside of the
Vandelliince, teeth are only found on the maxillary in Diplomyste of the Diplomy-
stidea of Chile.

Covering the end of the maxillaiy and joined to the dorsal surface of the base
of the barbel is a thin, comma-shaped bone, which may be the nasal.

Teeth, such as those described on the maxillary, have so far been noticed in
Va7idellia hasemani, sanguinea, and plazai. V. cirrhosa and T'. wieneri have not
been examined in this rcs]iect. Teeth like these are found in another member of
the family, Pareiodon (compare figures 21 and 34-35).

In Paravandellia and Branchioica the "claw-teeth" of the i)roximal part of
the maxillary are replaced by slender, pointed teeth, and there are more than one

360 MEMOIRS OF THE CARNEGIE MUSEUM.

series of tooth on the i)ronuixilhiry. In Branchioica a "claw-tooth" is present at
the end of the maxillarj'.

The rami of the lower mandibles of the Vandelliince seen from below are elon-
gate triangles, converging forward, but not joined, in fact, not meeting in the center.
Teeth may or may not be present in the lower jaw. When present, they are re-
curved, pointed, in two series at the end of the jaws, in apposition to the maxillary
teeth.

The alimentary canal is a simple, straight tube, of nearly uniform diameter,
evidently greatly distensible.

Key to the Species of Vandellia.
n. Mandible without teeth, thorn-like teeth at end of maxillary of V. plnzai and hasemnni. (Neither
mandible nor maxillary examined in V. cirrhosa and wieneri.)
b. Caudal truncate or slightly emarginate.

c. D. 8-9; A. 9-10; P. 6;*dcpth 9; premaxillaries with five to eight teeth; maxillary barbel two

in the head; caudal slightly emarginate, the lobes rounded, equal; pectorals longer than

the head 1. cirrhosa Cuvier & Valenciennes.

cc. D. 9; A. 8; P. 7; depth 12; premaxillaries with five to nine teeth; maxillary barbels less than
half the length of the head; caudal emarginate, the lobes rounded; pectorals as long as the

head 2. plazai Castelnau.

hh. Caudal forked; D. 11; A. 10; P. 0; depth 7-8.

d. Premaxillaries with nine teeth; mouth wide, angle of gape nearly opposite the maxillarj'

barbel; maxillary barbels about 3 in the head; distance between the origin of the dorsal
and origin of the caudal 2.75 in the distance of the dorsal from the snout; pectorals shorter

than the head 3. wieneri Pellegrin.

(III. Premaxillaries with about six teeth; mouth small, the angle of the gape far in advance of the
base of the barbel; maxillary barbel 2-2.5 in the head; distance between origin of dorsal
and base of middle caudal rays two and a quarter to two and one-half in its distance
from the snout; pectoral about equal to the length of the head.

4. hasemaai Eigenmann,

u(i. A patch of minute teeth on each mandible; one or two claw-like teeth on the end of the maxillary, just

in front of the barbels; caudal truncate; D. 11; A. 8; P. 6; premaxillaries with five teeth; maxillary

barbel two in the head; distance between origin of the dorsal and the origin of the caudal 2.8 in the

distance of dorsal from the snout; pectorals little shorter than the head. .5. sanguinea Kigenmann.

1. Vandellia cirrhosa Cuvier & Valenciennes.

Vandellia cirrhosa Cuvier & Valenciennes, Hist. Nat. Poi.ss., XVIII, 1846,
p. 386, pi. 547; Castelnau, Anim. Amer. du Sud, 1855, p. 51, pi. 28, fig. 2
(Brazil); GiJNTHER, Cat. Fishes Brit. Mus., V, 1864, p. 277; Eigenmann &
EiGENMANN, Proc. Cal. Acad. Sci. (2), II, 1889, p. 55 (Hyavary); Occasional
Papers Cal. Acad. Sci., I, 1890, p. 345; Proc. U. S. Nat. Mus., XIV, 1891,
p. 37; BouLENGER, Proc. Zool. Soc. Lond., 1897, pp. 901 and 920, Trans. Zool.

KIGENMANN: the PYGIDIID/E, a family of south AMERICAN CATFISHES. 361

Soc. Lond., XIV, 1898, p. 426; Jobert, Archiv. Parasit, I, 1898, p. 494; Pelle-
GRiN, Bull. Soc. Philom. Paris (10), I, 1909, p. ? (Apure, Manaos); Eigenmann,
Reports Princeton Univ. Exped. Patagonia, III, 1910, p. 401 ; Ribeiro, Comm.
de Linhas Telegraphicas Estrategicas de Matto-Grosso ao Amazonas, Annexe
5, 1912, p. 30 (Manaos).

Habitat. — Amazon and Orinoco basins; Rio Jurua; Hyavary; Manaos; Apur6.
This fish, the bad repute of which is widespread (see page 265) in South America,
is represented in Museums by only the few specimens in the following list, in part
copied from Pellegrin:

Jardin des Plantes, Paris, three, locality? Vandelli.

Jardin des Plantes, Paris, one, Apure. Geay.

Jardin des Plantes, Paris, two, Manaos. Anthony.

Mus. Comp. Zool., Cambridge, one, 40 mm., Hj-avary. Bourget.

British Mus., London, ? many, Jurua. Bach. "^

Mus. Nac. Rio de Janeiro, one, 94 mm., Manaos. Ribeiro.

Fig. 20. Vanddlia cirrhosa Cuvier & Valenciennes. (After Cuvier & Valenciennes.)

Head 8-10.5 (9-11.5 including the caudal); depth 9; D. 8-9; A. 9-10; P. 6.
Head slightly longer than wide; eye less than 3 in the head, greater than the snout;
six to ten spines on the opercle, five to ten on the interopercle; five to eight teeth on
the premaxillary ; origin of dorsal twice as far from tip of snout as from margin of
caudal; dorsal partly over anal.

362 MEMOIRS OF THE CARNECilE MUSEUM.

2. Vandellia plazai C'astelnau. (Plate LIII, fig. 3.)
Vandellia plazaii Castelnau, Anim. Amer. du Sud, Poissons, 1855, p. 51, pi. 28,
fig. 1 (Ucayale) ; Vaillant, Bull. Soc. Philom. (7), IV, 1880, p. 159 (Calderon);
Eigenmann & EiGENMANN, Proc. Cal. Acad. Sci. (2), II, 1889, p. 55 (Lake
Hyanuary); Occasional Papers Cal. Acad. Sci., I, 1890, p. 345; Proc. U. S.
Nat. Mus., XIV, 1891, p. 37; Pellegrin, Bull. Soc. Philom. Paris (10), I,
1909, p. ? (Calderon); Eigenmann, Reports Princeton Univ. Exped. Pata-
gonia, III, 1910, p. 401; RiBEiRO, Comm. de Linhas Telegraphicas Estra-
tegicas de Matto-Grosso ao Amazonas, Annexo 5, 1912, p. 30 (Manaos).
Vandellia plaza; GtJNTHBR, Cat. Fishes Brit. Mus., V, 1864, p. 277.

Habitat. — Middle and Upper Amazon basin; Ucayale, Calderon; Lake Hyan-
uary.

This species also is known from but few specimens, as follows:
Jardin des Plantes, Paris, ? Ucayale. Castelnau.
Jardin dcs Plantes, Paris, one, Calderon. Jobert.

Mus. Comp. Zool., Cambridge, Mass., one, 125 mm.. Lake Hyanuary. Bourget.
Mus. Nac. Rio de Janeiro, one, 67 mm., Manaos? Ribeiro.
7541, C. M., one, 66 mm. Dec. 9, 1909. Santarcm. Haseman.
It is principally distinguished by its more elongate form.

Fig. 30. Vandellia plazai Castelnau. Cam. Mus., No. 7541.

Head 9-11 (10-12 in the total length); depth 12-15.3 in the total length;
D. 9-10; A. 8-9; P. 7; twelve to sixteen opercular spines in 3 or 4 rows, seven or
eight on the interopercle ; head more rounded than in cirrhosa; barbel less than half
the length of the head; i)ectoral as long as the head; 8 or 9 teeth in the upper jaw.

3. Vandellia wieneri Pellegrin.
Vandeliia wieneri Pellegrin, C. R. Ac. Sc, November 29, Vol. 149, 1909, p. 1016;
Bull. Soc. Philom. Paris (1), X, 1909, p. 199, page of reprint 3, figure in the

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISH ES. 363

text; Mission Gcodesiquo dc I'Equateur, XII, 1912, p. 2, p. 10, pi. I, fig. 2,

near the mouth of the Rio IMisahually.

Habitat. — Rio Napo, Ecuador.

This species is known from the type. It is distinguished by its short body,
short barbel, and forked tail.
A. 9934, Paris Museum, one, 92 mm. Rio Napo near the mouth of the iMisahually,

Ecuador. Charles Wiener.

Fig. 31. Vandellia wieneri Pellegrin. (After Pellegrin.)

Head over 7; depth 7; D. 11; A. 10; P. 6; 9 teeth; lower jaw incised in middle,
without teeth; maxillarj' barbel about three in the head; eye two in the snout;
fifteen opercular spines in four series, directed obliquely upward and backward;
seven or eight interopercular spines in two rows; dorsal about two and three-fourths
times nearer caudal than snout; ventrals a Httle in advance of the last third of the
body; caudal peduncle 2.5 as long as high. Named for the collector, Mr. Charles
Wiener.

Fig. 32. Vandellia wieneri Pellegrin. (After Pellegrin.)

4. Vandellia hasemani Eigenmann. (Plate XVIII, fig. 3.)
7542, C. M., type, 72 mm.; 7543a-6, C. M., paratypes, 68 and 69 mm. Rio Ma-

mor^. Haseman.

Evidently similar to V. wieneri. Head 8-8.5; depth 8; D. 11; A. 10; P. 6.
Five or six teeth in the premaxillarics, two thorn-like teeth on the distal part of the
anterior face of the premaxillary, two or three more slender teeth on the distal part
of the lower face of the premaxillarj'; mandibular rami without teeth, widely
separated from each other, the membrane between the two rami but little emargi-
nate; angle of gape about halfway between the premaxillary and the barbel; maxil-

364

MEMOIRS OF THE CARNEGIE MUSEUM.

lary liarljol 2-2.5 in the Icnjith of the head; lower Imrbel minute; al)oiit ten inter-
oi)ercular thorns, fifteen or more on the operele; broad, free, flesh}' lobes behind the
opercular and pre-opercular spines; gill-openings about half as wide as the mouth;

Fig. 33. VandclUu hnscinani Eigcnnuuiii. Type, No. 7543a, Ciirn. Mus., 72 mm.

eye entirely in the anterior half of the head; the posterior nares nearly as large as
the ej'^es and between the anterior halves of the latter, anterior nares with a short
flap; pectorals about equal to the length of the head; origin of ventrals equidistant

Fig. 34. VandcUla hascmani Eigenmann. .1, .skull from above; B, hyomandibular and opercular
apparatus; C, end of ethmoid and preniaxillary teeth from in front, 1, premaxillary; 2, ethmoid; 5, frontal;
6, sphenotic; 7, pterotic; 8, supraoccipital; 9, epiotic; 10, suprachivicle; 1 1 , parapophysis of coalescep
vcrtebra>; 12, maxillary; 13, palatine; 14, mctapterygoid; 13, ciuadrate; 16, preopercle; 17, interoperclc;
IS, operele; 19, hyomandibular.

from ti]> of caudal and eye or operele, reaching a little beyond the anus; origin of
anal under middle of dorsal ; distance between anal and base of middle caudal rays
4.5-5.25 in the length; caudal forked for about two-ninths of its length; origin of

EIGENMANN: the PYGIDIIDiE, A FAMILY OF SOUTH AMERICAN CATFISHES. 365

dorsal over the tips of the ventrals, distance of origin of dorsal from caudal 2.25-2.5
in its distance from the snout.

Back and basal part of caudal truncate.

Fig. 35. Vandellia hasemani Eigenmann. .4, Left premaxillarj' from below, with two functional
and two relay teeth. B, left premaxillary of another individual with four teeth. C, the same, looking
at the edge of the teeth. D, premaxillarj' from below.

5. Vandellia sanguinea Eigenmann. (Plate LIII, fig. 2.)

Vandellia sanguinea Eigenmann, Proc. Am. Philos. Soc, LVI, Jan., 1918, p. 701.
7082, C. M., type, 62 mm. San Antonio de Rio Madeira. Nov. 3, 1909. Hase-

man.

This species differs from the others of the genus Vandellia in having concealed
teeth on the ends of the mandibles. It resembles them so much in other points
that it naturall}' raises the question whether these structures have not been over-
looked in V. cirrhosa and ivieneri. They cannot be seen without considerable effort.
The species greatly resembles V. plazai. Mr. Haseman noted that the specimen
was white (translucent?), the alimentary canal straight and gorged with blood.

Fui. 36. Vandellia sanguinea Eigenmann. No. 7082, Cam. Mus. Type, 62 mm.

366 MEMOIRS OF THE CARNEGIE MUSEUM.

Head 11.66; depth 12; D. 4 + 8.5; A. 3 + 7; P. 7; nearly the entire eye in the
anterior half of the head, a httle more than four in the length of the head to the tip
of the opercular spines. (The eye is too small in the drawings.)

Maxillarj- barbel extending to the tip of the interopercular spines, two in the
head; the lower barbel minute, onl}' about half a millimeter long as compared wath
the 2.5 mm. of the maxillary barbel; two flat, recurved teeth on the end of the

Fig. 37. Vandellia sanguitiea Eigenmann. Left premaxillarj', showing one of the concealed
teeth.

premaxillar}' concealed just in front of the barbel; five premaxillary teeth graduated
from the long middle one to the minute lateral ones; mandibles widely separated
from each other with about five minute teeth; the teeth concealed by the Hp; five
spines in the main row of the interopercle, the middle ones very strong, directed
backward, about five spines in supplementary rows; five spines in the main row of
the opercle, about ten in supplementary rows; distance from origin of ventrals to
base of middle caudal rays two times in its distance from the snout; origin of anal
behind the origin of the dorsal, the last dorsal ray over the middle of the anal; dis-
tance between anal and base of middle caudal rays five and one-half times in the
length; distance from origin of dorsal to base of middle caudal rays two and eight-
tenths times in its distance from the snout; caudal truncate, with numerous acces-
sorj' rays. Translucent, the ej'es black.

Genus X\'. Par.vv.wdellia" Ribeiro. (Plate XXXMII.)

Paravandellia Ribeiro, Comm. Linhas Telegraphicas Estrategicas de ]\latto-

Grosso ao Amazonas, Anne.xo Xo. 5, Sept., 1912, p. 29.

Type. — Paravandellia oxyptera Ribeiro.

No nasal or mental barbels, one (probably two) barbels at the angle of the
mouth; first pectoral ray not continued as a filament; gill-opening small; mouth
inferior, with a band of teeth in the middle of the upper jaw and a single series
lateraUj^; no teeth on the mandible; ventrals much nearer tip of caudal than snout;
opercular and interopercular spines separate from each other. Caudal forked
("furcada"). Ribeiro says that this genus may be considered between Stegophilus
and Vandellia, ha\nng the general appearance of the former.
*^ irapa = near,. Vandellia = name of a related genus.

EIGENMANN: the PYGIDIIDiE, A FAMILY OF SOUTH AMERICAN CATFISHES. 367

1 . Paravandellia oxyptera Ribciro.
Paravandellia oxyptera Ribeiro, /. c.

Habitat. — Paraguay River near Caceres.

Head triangular, eight times in the length including the caudal; D. 12; A. 10;
P. 7; dorsal behind the ventrals, partly over anal, both behind the middle of the
body; origin of dorsal nearer tip of caudal than base of pectorals; eyes without a free
margin, large, two and one-half times in head, equal to snout; maxillary barbel
reaching at most to tip of interopercular spines; pectorals large, falcate, one-fourth
longer than head, the first- ray longest, the next rapidly graduate, the outer rays
longer again; caudal forked, the upper lobe a little the longer; anal similar to the
dorsal, under the last rays of the latter.

White, the eyes black

The single specimen of this genus and species known, 22 mm. long, was taken
in the same locality in which the Ochmacanthus {Gyrinurus) batrachostoma was
caught, among the "pseudo-rhyzomas de Agua-pe" Eichornea azurea, in the margin
of the Paraguay River near San Luiz de Caceres.

Genus XVI. Branchioica Eigenmann."*^
Branchioica Eigenmann, Proc. Am. Phil. Soc, LVI, Jan., 1918, p. 702.

Type. — Branchioica bertonii Eigenmann.

It is quite possible that this genus will, on direct comparison of specimens, prove
a synonym of Paravandellia. It has the same general characters, but comes from
the lower Paraguay, while Paravandellia comes from the upper. The present species
was taken from a fish, while Paravandellia seems to be free swimming. It is quite
possible that teeth will be found in Paravandellia at the end of the maxillary (pre-
maxillary?) and on the mandibles when they are examined minutely. Paravan-
dellia is said to have the caudal forked, while Branchioica has it subtruncate.

No nasal or mental barbels, two barbels at angle of the mouth, of which the
lower is minute; first pectoral ray not spinous, not prolonged in a filament; gill-
openings small, the membrane perfectly confluent with the isthmus; mouth inferior;
two series of teeth in the front of the u])per jaw, a single series of much smaller teeth
laterad of these; maxillary with claw-like teeth at its end, just in front of the barbel
and entirely concealed; two short series of teeth on the ends of the mandibles,
opposite the lateral series of teeth of the upjier jaw, the two rami of the mandibles
not meeting; opercular and interopercular patches of spines separate from each
other; caudal subtruncate.

*' Pp&yxia, TO. = the gills of fishes; imfu = to inhabit.

368 MEMOIRS OF THE CARNEGIE MUSEUM.

The first specimen of this genus was received and described several years ago.
Both the specimen and description were forgotten, the latter never published. The
two specimens 13950 T. U. M. were received much later and independently
described.

2. Branchioica bertonii Eigenmann. (Plate XLIII, figs. 3-5.)
Branchioica bertoni Eigenmann, Proc. Am. Philos. Soc, LVI, Jan., 1918, p. 703.
13950, I. U. M., type, 24 mm., paratj^pe about the same length over all, much

curved. Taken from a large Characin, Piaractus brachypomus (Cuvier).

Asuncion, Paraguay. Collected by A. de W. Bertoni.
7545, C. M., paratype, 24 mm. Puerto Bertoni, Alto Parana, from the branchia of

Piarnctus brachypoimifi (Cuvier). Bertoni.

Fig. 38. Branchioica bertonii Eigenmann. a, mandible; b, left maxillary with its five teeth; c,
I)(irti<in of another maxillary, showing the proximal teeth only.

Head about 5.5; depth 5.5; D. 10; A. 7; P. 6; eyes superior, nearly the entire
eye in the anterior half of the head, 3.5 in the head, about equal to the length of the
snout, considerably larger than the interorbital ; maxillary barbel extending to very
near the interopercular spines, the lower barbel very minute; caudal peduncle
slender, abdomen well rounded; premaxillary with two irregular series of slender,
liointcd teeth, those of the posterior series much the larger, about five in number,
subequal, both series graduated from the larger ones nearer the center outward;
laterad of the median series (on the premaxillary?) are four or five similar but smaller
teeth, graduated from the larger proximal one; the rami of the lower jaw widely
separated from each other, each with about five, recurved, pointed teeth in two
series on its end, in apposition to the lateral series of the upper jaw; gill-opening
minute, circular, gill-membranes perfectly confluent with the isthmus; opercle
with a bunch of about twelve, subequal, upward directed spines; interopercle with
about eleven curved, downward directed spines, arranged in two series; distance
from origin of ventrals to caudal 1.6 in its distance from the snout, origin of anal
behind the origin of the dorsal; distance between anal and caudal about 5 in the
length; pectoral falcate, the outer ray not prolonged as a filament, about as long
as the head; origin of dorsal between that of the ventrals and anal, twice as far

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 369

from snout as from caudal; caudal narrow, obliquely rounded or subtruncate, with
few inconspicuous fulcra.

Translucent; eyes black; chromatophorcs on the snout, along the back, along
the base of the anal, on the base of the caudal, along the side of the abdominal
cavity, and a few on the pectoral.

Genus XVII. Tridens Eigcnmann & Eigcnmann. (Plate XXXIX.)

Tridens Eigenmann & Eigenmann, Proc. Cal. Acad. Sci. (2), I, 1889, p. 53.

Type. — Tn'denH melnnops Eigcnmann & Eigenmann.

Anal long, with twenty or more rays, its origin in front of that of the dorsal;
ventrals small, nearer to tip of snout than to base of caudal; head greatly depressed,
the eye lateral, infringing on the upper and lower surfaces; a series of fine labial
teeth, stronger teeth in the jaws; gill-membranes united, forming a broad, free fold
across the isthmus; no nasal or mental barbel, two maxillarj' barbels; opercle and
interopercle armed, the patches of spines separate. >

The two species originally placed in this genus differ so greatly that they should
probably be ])laced in separate genera. The specimens known are all very small,
27 mm. and less.

Key to the Species of Tridens.
a. Depth 13; head 9; D. 10-12; A. 20-2.5; opercle with three spines; barbels minute, scarcely evident;

distance between origin of dorsal and tip of caudal three in the length; distance between origin of

anal and tip of caudal two and five-tenths in the length; caudal rounded, without accessory rays.

1. melanops Eigenmann & Eigenmann.
aa. Depth 6; head 6; D. 9; A. 22; opercle with 6 or more sphies; maxillary barbel extending to the base of

the pectoral; distance between origin of dorsal and tip of caudal two in the length; distance between

origin of anal and tip of caudal less than two in the length; caudal cmarginate; eye large, nearer end

of opercle than tip of snout; first pectoral ray greatly produced.

2. brevis Eigenmann & Eigenmann.

1. Tridens melanops Eigcnmann & Eigenmann. (Plate XLIII, figs. 1-2.)

Tridens melcmops Eigenmann & Eigenmann, Proc. Cal. Acad. Sci. (2), II, 1889,
p. 53 (I^a); Occasional Papers Cal. Acad. Sci., I, 1890, p. 339; Proc. U. S. Nat.
Mus., XIV, 1891, p. 37; Eujenmann, Reports Princeton Univ. Exped. Pata-
gonia, III, 1910, p. 401.

Habitat. — I^a, near boundary between Brazil and Peru.
Known from the types, the largest 27 mm., in the Museum of Comparative

Zoology, one of which was received by Indiana University in 1891 and bears the

number 4245.

Head 9; depth 13; D. 10-12; A. 20-25.

370 MEMOIRS OF THE CARNEGIE MUSEUM.

Body compressed, extremely slender. Head broad, the snout rounded; mouth
broad, inferior. Ojiercle long and slender, terminating in three spines, trident-
shaped. Pre-opercle with .similar but smaller spines. Barbels minute, scarcely
evident. Distance of origin of dorsal fin from extremity of caudal 3 in the length;
origin of anal fin from extremity of caudal 2.5 in the length. Anal rays rapidly
decreasing in height backward, the last ray about under the last ray of the dorsal.
Caudal rounded, without acce.s.sory rays.

Yellowish; posterior half of the caudal fin dusky; a series of black spots along
the base of the anal.

2. Tridens brevis Eigcnmann & Eigenmann.

Tridens brevis Eigenm.\nn & Eioenmann, Proc. Cal. Acad. Sci. (2), II, 1889, p. 54

(Tabatinga); Occasional Papers Cal. Acad. Sci., I, 1890, p. 340; Proc. U. S.

Nat. Mus., XIV, 1891, p. 37; Eigenmann, Reports Princeton Univ. Exped.

Patagonia, III, 1910, p. 401.

Habitat. — Tabatinga.

Known from the type, 21 mm. long, in the Museum of Comparative Zoology.
A recent search for it has failed to locate it.

Head 6; depth 8; D. 9; A. 22.

Body short and deep. Head as broad as long; mouth broad, inferior. • Opercle
with a bunch of six or more spines; pre-opercle with a smaller bunch of spines.
Barbels well developed, the outer one extending to the base of the pectoral, the
inner to the gill-opening. Eye large, nearer end of opercle than tip of snout. Dis-
tance of origin of dorsal from tip of caudal Httle more than two in the length. Anal
inserted very little in front of the dorsal and extending some distance beyond it,
its rays decreasing in height toward the caudal. Origin of anal from extremity of
caudal less than 2 in the length. First pectoral ray greatly produced. Caudal
emarginate.

Yellowish; blackish dots along the bases of the fins; a series of blackish dots
along the middle line of the sides; similar spots on the back. Head with brown dots.

Genus XVIII. Miuroglanis''^ Eigenmann & Eigenmann. (Plate XXXIX.)

Miuroglanis Eigenmann & Eigenmann, Proc. Cal. Acad. Sci. (2), II, 1889, p. 55.

Type. — Miuroglanis platycephalus Eigenmann & Eigenmann.

Anal long, with fifteen rays, its origin in front of that of the dorsal; no nasal or
mental barbel; two barbels at angle of mouth; head greatly depressed, eye lateral,

*^ iidovpm = curtailed ; 7X01/15, 6 = a catfish.

EIGENMANN: the PYGIDIID^, a PAMILY of south AMERICAN CATFISHES. 371

behind the angle of the mouth; mouth subinferior; several series of strong teeth in
each jaw; gill-membrane broadly united with the isthmus, without a free margin;
opercular and subopercular patches of spines confluent.

1. Miuroglanis platycephalus Eigcnmann & Eigenmann.

Miuroglanis plahjcephalus Eigenmann & Eigenmann, Proc. Cal. Acad. Sci. (2),

II, 1889, p. 56 (Jutahy); Occasional Papers Cal. Acad. Sci., I, 1890, p. 347;

Proc. U. S. Nat. Mus., XIV, 1891, p. 37; Eigenmann, Reports Princeton

Univ. Exped. Patagonia, III, 1910, p. 401; Ribeiro, Fauna Bras., IV (A),

1912, p. 227.

Habitat. — Jutahy.

Known from the type 17 mm. long, collected during the Thayer expedition by
WiUiam James. A recent search for it in the collections of the Mus. Comp. Zool.
has failed to locate it.

Head 5.5; D. 10; A. 15. Body short, compressed, and rather deep. Head
greatly depressed, wider than long. Eye large, lateral, placed behind the angle of
the mouth. Mouth subinferior, the upper jaw projecting shghtly. Upper maxil-
lary barbel scarcely extending to the gill-opening; no nasal barbels. The opercular
and pre-opercular patches of spines united. Origin of the dorsal fin Uttle behind
that of the anal, its distance from the tip of the snout somewhat less than twice its
distance from the tip of the caudal.

Appendix to the Monograph on the Pygidiid^.
PHREATOBIUS" Goeldi.

Phreatobius Goeldi, C^omptes Rcndus Gongres Intern. Zool., Berne, 1904, p. 549;

Fuhrmann, Verhandl. Schweitz. Naturf. Gesellsch. Aarau, 1905, p. 50;

Archives des Sciences Phys. Nat. Geneve (4), 20, 1906, p. 578.

Type. — Phreatobivs cisternarum Goeldi.

Origin of dorsal slightly in front of origin of the ventrals, much nearer snout
than to caudal; no nasal barbel; maxillary barbel similar and about as long as the
two mental barbels, placed nearer the anterior nares than to the angle of the mouth;
the mental barbels of each side close together, but remote from their fellows of the
other side, placed directly below the maxillary barbel; mouth terminal, wide, the
lower jaw projecting; teeth in the upper jaw in about three series, in two series in
the lower jaw in front, in one series on the side; the inner teeth the larger and in
very regular series; gill-membrane extending but little above the base of the pec-

" <t>piap, TO = cistern ; /Sios, 6 = life.

372

MEMOIRS OF THE CARNEGIE MUSEUM.

toral, narrowly joined to the isthmus at a point about half-way between its pos-
terior angle and the snout; first pectoral ray not spinous; anal very long, its origin
under the end of the dorsal, its base more than one-third of the length; caudal small,
accessory rays large and numerous, continuous with the anal fin and extending as a
similar fin on the back for two-fifths of the distance to the snout ; opercle and inter-
opercle unarmed; eyes rudimentary, near the posterior nares.

This genus is distinguishable by the concomitant elongation of the caudal
portion of the body, the anal fin and the accessory portion of the caudal, by the
position of the dorsal in relation to the ventrals and by the development of the
barbels and absence of opercular armature.

1. Phreatobius cisternarum Gocldi. (Plate LVI, figs. 1, 2 and 4.)
Phreatobius cisternarum Goeldi, Comptes Rendus Congres intern. ZooL, Berne,
1904, p. 549; Fuhrmann, Verhandl. Schwcitz Naturf. Gesellsch. Aarau, 1905,
p. 50; Archives des Sciences Phys. Nat. Geneve (4), 20, 1906; p. 578 (aUied to
Clariidce, not to Leptosidce and Trycliomyoerice; fide Zoological Record).

Fig. 39. Phreatobius cisternarum Goeldi. (By permission of Dr. 0. Fuhrmann.)

The generic as well as specific descriptions of this species are drawn from photo-
graphs lent me by Dr. O. Fuhrmann, and from a specimen 40 mm. long, also sent

EIGENMANN: the PYGIDIID^, a family of south AMERICAN CATFISHES. 373

me by Dr. Fuhrmann, whose generosity, since he himself proposes to pubHsh an
account of the anatomy of the species, I greatly appreciate.
7603, C. M., 40.5 mm. Marajo. From Dr. O. Fuhrmann.

Head about 7; depth about 12; D. 7 (showing in photograph); A. about 25
(showing in photograph).

Heaviest at back part of head, tapering regularly to the base of the caudal, the
depth of which is about one-third that of the head ; mental barbels in pairs, not reach-
ing pectoral, maxillary barbels sometimes to middle of pectoral; j^ectoral short and
narrow, but little more than half as long as the head; distance from snout to origin of
ventrals about one and a half in the distance between caudal and origin of ventrals;
caudal small, rounded, one and one-half in the length of the head; origin of dorsal
m advance of that of the ventrals, its last ray about over origin of anal; upper acces-
sory caudal rays beginning about over the origin of the second third of the anal, the
highest one but httle lower than the dorsal rays; anal continuous with the lower
accessory caudal rays; ventrals a httle shorter than the pectorals. Color uniform

Memoirs Carnegie Museum, Vol. VII.

Plate XXXVI.

KNOWN DISTRIBUTION OF THE PYGIDIIN/E.

A Known distribution of f„;dium. Probably in all
mountain streams north of the latitude of Buenos
Aires and sporadically in lowlands. The localities in
Southern Chile not indicated.

^ Known distribution of Hatcheria.

Known distribution of Sclennema.

Known distribution of Enmopkilus.

Memoirs Carnegie Museum. Vol. Vll.

Plate XXXVII.

STRIBUTION OF STEGOPHILIN/t.
Homodimtus anisitsi.
Homodimius maculatus.
Henonemus macrops.
Henonemus intermedius
Henonemus punctatus.
Henonemus taxisligmus.
Slegophilus insidiosus.
Acanlhopoma annectens.
Ochmacanthus katnchostomus,
Ochmacanthus reinhardti.
Ochmacanthus BaMliftrus.

Memoirs Carnegie Museum. Vol. VII,

Plate XXXVIII.

DISTRIBUTION OF THE VANDELLIIN/€.

Vandellia cirrhosa.
Vandeltia plazai.
Vandellia wteneri.
Vandellia hasemani.
Vandellia sanguinea.
Paravandellia ox/ptera.
Branchioica bertonii.

^^:

Memoirs Carnegie Museum, Vol. VII.

Plate XXXIX.

f?

i 1 .it

KNOWN DISTRIBUTION OF THE PAREIODONTIN/E.
^B Pareiodon mi'crops Kner.

KNOWN DISTRIBUTION OF THE TRIDENTIN/E,
I I Miuroghnis p/atycepha/us E. & E.
^^ Trident melanops E. & E.
■H Tridens brans E. d E.

376 MEMOIRS OF THE CARNEGIE MUSEUM.

EXPLANATION OF PLATE XL.

A and 5, Eremophilus mutisii Humboldt; C, Henonemus pundatus (Boulenger).

1, Preniaxillary; 2, Ethmoid; 3, Lateral Ethmoid; 4, Nasal; 5, Frontal; 6, Sphenotic;
7, Pterotic; 8, Supraoccipital: 9, Epiotic; 10, Supraclavicle; 11, Parapophysis of coalesced
vertebrsc; 12, Maxillary; 13, Palatine; 14, Metapterygoid; 15, Quadrate; 16, Pre-opercle;
17, Intcropercle; 18, Opercle; 19, Hyomandibular; a, clavicle from the side; b, posterior
face of clavicle.

378 MEMOIRS OF THE CARNECIE MUSEUM.

EXPLANATION OF PLATE XLI.

Figs. 1-2. Eremophilus mutisii Humboldt. The air-bladders show faintly as two
bags, one on either side of the origin of the vertebral column in fig. 2; and as a small
vesicle just above the column in fig. I. The outlines are marked with a few dots.

Figs. 3—4. Paracetopsis occidentalis (Steindachner). The air-bladder shows as a
large bag in fig. 3. A few points are placed in its wall to call attention to its outline.

The tails in figures 1 and 3 are from the same negatives as the rest of these figures,
but have been printed heavier, as these portions are thin, and the negatives otherwise
quite faint.

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Memoirs Carnegie Museum, Vol. VII.

Plate XLII.

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Figs. 1-2. N emaioqeny^^ inermis (Guichenot). Aftkh Eigenm.\nn. From No. 9839, M. C.

Z., CURICO, S.\NTIAGO, ClIILE.

Figs. 3-5. //«^c/*m« //mc»/a<a (Cuvier & V.^lenciennes). After Eigenmaxn. I<rom JNo.
773G, M. C. Z., 92 mm. M.'vpocho, Chile.

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380 MEMOIRS OF THE CARNEGIE MUSEUM.

EXPLANATION OF PLATE XLIV.

Fig. 1. Scleronema operculatutn Eigenmann. Type, No. 7077 C. M., 79 mm.,
Cacequy.

Fig. 2. Hatcher ia litcornbi Eigonmann. Type, No. 11110 I. U. M., 164 mm.,
Arroyo Comajo.

Fig. 3. Pygidium eichorniarum Ribeiro. No. 7560a, C. M., 40 mm., San Antonio,
Rio Guapore.

Fig. 4. Pygidium. helerodonium Eigenmann. Type, No. 13832 I. U. M., 83 mm.,
Rio Mendoza, Argentina.

Fig. 5. Pscudostegophilus nemurus (Giinther). No. 7547 C. M., 78 mm., Rio
Mamor^.

Memoirs Carnegie Museum, Vol. vil.

Plate XLIV.

'A.

_ yAiffwfft^-TT^'"""''"-'^" "'"'"I^^T'tj y"

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Scleronevia, Hatcheria, Pygidium, and Pseudostegophilus.
(For detailed explanation see opposite page.)

382 MEMOIRS OF THE CARNEGIE MUSEUM.

EXPLANATION OF PLATE XLV.

Fig. 1. Pygiclium punctaiissimum (Castelnau) after Castelnau.

Fig. 2. Pygidium rivulatum (Cuvier & Valenciennes). After Castelnau's figure of
Trichomyclerus pentlandi.

Fig. 3. Pygidium rivulatum (Cuvier & Valenciennes). After Castelnau's figure of
Trichmnycicrus pictus.

Fig. 4. Pygidium punctulatum (Cuvier & Valenciennes). After Cuvier & Valen-
ciennes.

Fig. 5. Pygidium dispar Tschudi. After Tschudi.

Memoirs Carnegie Museum, Vol. VII.

Plate XLV.

Pygidium.
(For (Iclailcil cxijlanalion sec opposite page.)

Memoirs Carnegie Museum, Vol. VII.

Plate xlvi.

Figs. 1,2. P yy idium kneri {Steindachner). Akter Steindachner.
Figs. 3, 4. Pijijidium amazonlcum (Stkindachmch). Attkh Steindaciiner.
Fig. 5. Pijgidium taczamnrskii (Stkindaciinek). After the male of Pygidium dispar
TscHUDi, Faun. Peruana, Itimivoi.., vi.. Ill, lower figure.

Figs. 6-8. Pijgidium laczunowskii (Steindachner). After Steindachner.

384 MEMOIRS OF THE CARNEGIE MUSEUM.

EXPLANATION OF PLATE XLVII.

Fig. I. Pygidium siellaium Eigenmaiin. Typo, No. 7097 C'. M., 78 mm., Quebrada
Sargento.

Fig. 2. Pygidmm chapmani Eigenmann. Type, No. 4817, C. M., 106 mm.,
Bo(iuia.

Fig. 3. Pygidium chapmani P^igenmann. No. 7091 C. M., 86 mm., Rio Dagua at
Caldas. Eigeiimann.

Fig. 4. Pygidium latidens Eigenmann. Type, No. 13801, I. U. M., .53 mm.,
near mouth of Rio Calima, Colombia. (Head too short ; it is 5.5 in the length.)

Fig. 5. Pygidium metce Eigenmann. Type, No. 13770, L U. M., Barrigona.

Memoirs Carnegie Museum, Vol. Vll.

Plate XLVII.

'-'- 'i«^ v,*.;! "•:.;..!.

, ♦ •

Pygidiuiii.
(For detailed explanation sec opposite page.)

386 MEMOIRS OF THE CARNEGIE MUSEUM.

EXPLANATION OF PLATE XLVIIL

Fig. L Pygidium banneaui Eigenmann. Type, No. 4815, C. M., 43 mm., Bernal
Creek.

Fig. 2. Pygidium spilosoma Regan. No. 7092, C. M., 97 mm., Cordova, Rio
Dagua, Colombia.

Fig. 3. Pygidium dorsoslrialum Eigenmann. Type, No. 7093a, C. M., 76 mm.,
Villavicencio.

Fig. 4. Pygidium latistriahun Eigenmann. Type, No. 7450, C. M., 46 mm.,
Quebrada de l^incliote, Santander.

Fig. 5. Pygidium regani Eigenmann. No. 13772, I. U. M., 55 mm., Tado.

Memoirs Carnegie Museum, Vol. VII.

Plate XLVIII

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Pygidium.
(For detailed explanation sec opposite page.)

388 MEMOIRS OF THE CARNEGIE MUSEUM.

EXPLANATION OF PLATE XLIX.

Fig. 1. Pygidium stramineum Eigenmann. Type, No. 7101, C. M., 46 mm.,
Quebrada del Mango. (The eye is farther forward than in the specimen.)

Fig. 2. Pygidium meridce Regan. No. 13771, L U. M., 99 mm., Merida, Venezuela.

Fig. 3. Pygidium bogotense Eigenmann. Type, No. 4820, C. M., 74 mm., Puente
de Supa, near Chapinero, Plains of Bogota.

Fig. 4. Pygidium bogotense Eigenmann. No. 48216, C. M., 70 mm., Chapinero.

Fig. 5. Pygidium nigromaculatum (Boulenger). Univ. Michigan, 165 mm., San
Lorenzo, Santa Marta Mountains, 4,500 ft.

Memoirs Carnegie Museum, Vol. VII.

Plate XLIX.

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Pyqidium.
(For detailed explanation see opposite page.)

390 MEMOIRS OF THE CARNEGIE MUSEUM.

EXPLANATION OF PLATE L.

Fig. L Pygidium guianense Eigenmann. Type, No. 1003, C. M., 77 mm., Arua-
taima Cataract.

Fig. 2. Pygidium conradi Eigenmann. Type, No. 2212, C. M., 41 mm., Amatuk
Cataract. (The head is a little too short.)

Fig. 3. Pygiditim graciUor Eigenmann. Type, No. 1730, C. M., 27 mm., Erukin,
British Guiana.

Fig. 4. Pygidium hasemani Eigenmann. Type, No. 5238, C. M., 15 mm., San-
tar em.

Fig. 5. Pygidium iheringi Eigenmann. Type, No. 10785, I. U. M., IGl ram.,
Santos.

Memoirs Carnegie Museum, Vol. VII.

Plate L.

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(For detailed explanation see opposite page.)

392 MEMOIRS OF THE CARNEGIE MUSEUM.

EXPLANATION OF PLATE LL

Fig. 1. Pygidium zonatum Eigenmann. Type, No. 7596, C. M., 62 mm., Agua
Quente.

Fig. 2. Pygidium prodps (Ribeiro). No. 7593, C. M., 60 mm., Agua Quente. .

Fig. 3. Pygidium paolence Eigenmann. Type, No. 7081, C. M., 68 mm., Alto da
Serra, Rio Tiete, Siio Paulo, Brazil.
EWWTA- Fig. 4. Pygidium. reinhardtit Eigenmann. Type, No. 7078, C. M., 65 mm.,

Burmier.

Fig. 5. Pygidiwn davisi Haseman. Type, No. 2862, C. M., 52 mm., Serrinha
Parana.

Memoirs Carnegie Museum, Vol. VII.

Plate LI.

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Pxjgidium.
(For detailed explanation sec opposite page.)

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394 MEMOIRS OF THE CARNEGIE MUSEUM.

EXPLANATION OF PLATE LIL

Fig. 1. Pygidium immaculatum Eigenmann & Eigenmann. No. 7076, C. M., 81
mm., Rio Doce.

Fig. 2. Pygidium vermiculatum Eigenmann. Type, No. 7074, C. M., 131 mm.,
Juiz de Fora.

Fig. 3. Pygidium alternatum Eigenmann. Type, No. 7079a, C. M., 79 mm., Rio
Doce.

Fig. 4. Pygidium irigutiatum Eigenmann. Type, No. 7600a, C. M., 36 mm.,
Jacarehy.

Fig. 5. Pygidium santce-ritce Eigenmann. Type, No. 7599, C. M., 24 mm., Santa
Rita.

Memoirs Carnegie Museum, Vol. VII.

Plate LII.

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GUIDE TO CONTENTS.

PAGE

Introduction 259

Pariolius (Footnote) 260

Habits 261

Distribution of the Pygidiidse (Plates XXXVI-XXXIX) 269

Chronology 270

Location of types 271

Sources of the material examined 274

Zoological position of the Pygidiidae 275

Synonymy 275

Limits of the family Pygidiidae (Plates XL-XLI) 276

Key to the subfamilies and genera (Text figure 1) 278

I. Nemalogenys 279

A', inermis (Plate XLII, figs. 1 and 2) 280

II. Scleronema (Plate XXXVI, text figure 2) 280

S. operculatum (Plate XLIV, fig. 1) 281

III. Hatcheria (Plate XXXVI, text figure 2) 281

1. H. patagoniensis (Text figure 3) 283

2. H. maculata (Plate XLII, figs. 3-5) 284

3. H. titcomhi (Plate XLIV, fig. 2) 284

4. H. areolata (Text figure 4) 285

5. H. burmcisteri (Text figure 5) 286

6. H. macroei (Text figure 6) 287

IV. Pygidium 288

1 . P. marmoratum 290

2. P. pnlleum , 291

3. P. tigrinum 291

4. P. tenue (Text figure 7) 292

5. P. corduvense (Text figure 8) 293

6. P. spegazzinii 294

7. P. borellii 294

?8. P. eichornmrum (Plate XLIV, fig. 3) 295

9. P. riojanum Berg 295

395

396 MEMOIRS OF THE CARNEGIE MUSEUM.

PAGE

10 P. heferodontum (Plate XLIV, fig. 4) 296

11. P. fuscum 298

12. P. eigenmanni 298

13. P. vittatim . .' 299

14. P. dispar (Plate XLV,fig. 5) 299

15. P. punctulatum (Plate XLV, fig. 4) 300

16. P. taczanowskii (Plate XLVI, figs. 5-8) 300

17. P. rivulatum (Plate XLV, figs. 2 and 3) 301

18. P. poeyanum 302

19. P. barbouri (Text figure 9) 303

20. P. fassli 303

21. P. oroycB (Text figure 10) 304

22. P. quecfmorum (Text figure 11) 305

23. P. laticeps ■ (Text figure 12) 307

24. P. stellatum (Plate XLVII, fig. 1) 308

25. P. chapmani (Plate XLVII, figs. 2 and 3; Text figure 13) 309

26. P. twniu7n (Text figure 14) 310

27. P. caliense (Text figure 15) 311

28. P. latidens (Plate XLVII, fig. 4) 312

29. P. meUB (Plate XLVII, fig. 5) 312

30. P. stramineum (Plate XLIX, fig. 1) 313

31. P. unicolor 314

32. P. kneri (Plate XLVI, figs. 1 and 2) 314

33. P. meridce (Plate XLIX, fig. 2) 315

34. P. bogotense (Plate XLIX, figs. 3 and 4) 315

35. P. nigromaculatum (Plate XLIX, fig. 5) 317

35. P. banneaui (Plate XLVIII, fig. 1) 318

37. P. spilosoyna (Plate XLVIII, fig. 2) 319

38. P. dorsoslriatum (Plate XLVIII, fig. 3) 320

39. P. venulosum 320

40. P. latistriatum (Plate XLVIII, fig. 4) 321

41 . P. striatum 321

42. P. regani (Plate XLVIII, fig. 5) 323

43. P. retropinne 324

44. P. guianense (Plate L, fig. 1) 325

45. P. conradi • -^ ■ ■ ■ (Plate L, fig. 2) 325

46. P. gracilior (Plate L, fig, 3) 326

EIGENMANN: the PYGIDIIDiE, A FAMILY OF SOUTH AMERICAN CATFISHES. 397

PAGE

47. p. amazonicum (Plate XLVI, figs. 3 and 4) 326

48. P. hasemani ". (Plate L, fig. 4) 326

49. P. nigricans 329

50. P. iheringi (Plate L, fig. 5) 330

51. P. zonaium (Plate LI, fig. 1) 330

52. P. proops (Plate LI, fig. 2; Text figure 16) 331

53. P. paolence (Plate LI, fig. 3) 332

54. P. reinhardti (Plate LI, fig. 4) 333

55. P. davisi (Plate LI, fig. 5) 334

56. P. immaculatum (Plate LII, fig. 1) 334

57. P. vermiculatum (Plate LII, fig. 2) 335

58. P. alternatum (Plate LII, fig. 3) 336

59. P. goeldii 337

60. P. brasiliense (Text figures 17 and 18) 337

61. P. itatiayce . (Text figure 19) 339

62. P. triguttatmn (Plate LII, fig. 4) 339

63. P. punclatissimum (Plate XLV, fig. 1) 340

64. P. minutum (Text figure 20) 340

65. P. santoe-ritce (Plate LII, fig. 5) 341

V. Eremophilus (Plate XXXVI; Plate XL, figs. A and B) 341

1. E. mutisii . . . (Plate XLI, figs. 1 and 2; Plate LIV, figs. 1 and 2) 341

VI. Pareiodon (Plate XXXIX, text figure 21) 343

1. P. microps (Plate LIV, fig. 3) 344

VII. Henonemus (Plate XXXVII) 345

1. H. macrops (Text figure 22) 346

2. H. punctatus (Plate XL, fig. C; Text figures 23 and 24) 346

3. H. taxistigmus (Text figure 25) 348

4. H. intermedius 349

VII. Pseudostegophilus 349

1. P. nemurus (Plate XLIV, fig. 5) 350

IX. Homodioclus (Plate XXXVII) 350

1. H. anisitd (Plate LVI, figs. 3 and 5) 351

2. H. maculatus (Text figure 26) 352

X. Stegophilus (Plate XXXMI) 353

1. S. insidiosus (Text figure 27) 353

XI. Acanthopoma (Plate XXXVII) 354

. 1 . ^ . annectens (Text figure 28) 355

398 MEMOIRS OF THE CARNEGIE MUSEUM.

PAGE

XII. Ochmacanthus. (Plate XXXVII) 355

1. 0. batrachostoma (Plate LV, figs. 1-3) 356

2. 0. reinhardti. (Plate LV, fig. 4) 357

3. 0. flabelliferus (Plate LV, fig. 5) 357

XIII. VandelUa (Plate XXXVIII) 358

XIV. Urinophilus 359

1. V. cirrhosa (Text figure 29) 360

2. V. plazai (Plate LIII, fig. 1; text figure 30) 362

3. V. ivieneri (Text figures 31 and 32) 363

4. F. hasemani (Plate LIII, fig. 3; text figures 33, 34 and 35) 363

5. V. sanguinea (Plate LIII, fig. 2; text figure 36 and 37) 365

XV. Paravandellia (Plate XXXVIII) 366

1. P. oxyptera 367

XVI. Branchioica. (Plate XXXVIII) 367

1. B. hertonii (Plate XLIII, figs. 3-5; text figure 38) 368

XVII. Tridens (Plate XXXIX) 369

1. T. melanops (Plate XLIII, figs. 1 and 2) 369

2. T. hrevis 370

XVIII. Miuroglanis (Plate XXXIX) 370

1 . M. platycephalus 371

Appendix

Phreatobius 371

P. cisternarum (Plate LVI, figs. 1, 2 and 4; text figure 39) 372