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HARVARD UNIVERSITY 

Library of the 

Museum of 

Comparative Zoology 



Bulletin of the Museum of Comparative Zoolog^y 

AT HARVARD COLLEGE. 

Vol. LXVII. No. 1. 



SOME TRILOBITES OF THE LOWER MIDDLE ORDOVICI AN 
OF EASTERN NORTH AMERICA. 



By Percy E. Raymond. 



With Ten Plates. 



CAMBRIDGE, MASS., U. S. A.: 

PRINTED FOR THE MUSEUM. 

April, 1925. 



No. 1. — Somr Trilohitrs of the Lower Middle Ordoincian of 
Eastern North America. 

By Percy E. Raymond. 

This paper is concerned primarily with the trilobites of the lower 
part of the Middle Ordovician of the Appalachian Province. It is 
based upon collections made hy the writer during expeditions to 
Pennsylvania, Virginia, and Tennessee, the cost of which was de- 
frayed by the Shaler Memorial Fund at Harvard University. These 
trips were made in 1917, 1918, and 1921, and although primarily for 
the study of the stratigraphy of the Ordovician formations of the 
region, it soon l^ecame obvious that the perplexing problems presented 
could not be solved until the faunas were described. 

Knowing my interest in the faunas of this age, Professor Schuchert 
very kindly turned over to me for study and description all the trilo- 
bites collected by himself, and by Professors Twenhofel and Dunbar, 
on three expeditions to western Newfoundland. A number of these 
species proved to be undescribed, and others were represented by 
specimens which threw new light on their relationships. A collection 
made by the late Alpheus H\att in the same region many ^ears ago 
also contains trilobites which added to the knowledge of this fauna. 

In order to have material for comparison, the C'hazy of western 
Vermont and northeastern New York was again explored in 1919, and 
a few new trilobites are now added to that rather extensive fauna. 

Besides these strictly Lower ]Mifldle Ordovician species, a few 
others, more or less germane to the subject, are described. A trip to 
Clermont, Iowa, in 1917, produced a few new forms from that astonish- 
ingly fertile locality, and former students have been good enough to 
send me specimens from ^Missouri and British Columbia. 

My thanks are due to Profs. Roy Holden of Blacksburg and S. L. 
Powell of Salem, Va., for specimens which they have enabled me to 
use; to Prof. E. W. Shuler of Dallas, Texas, for others collected during 
his study of Walker Mt., Va.; to Prof. R. M. Field for specimens col- 
lected while with me in Virginia in 1917; to Mr. A. G. Becker for 
assistance and specimens when at Clermont, Iowa; to Dr. Donald G. 
Barton for extensive collections from the Kimmswick of Missouri; to 
Dr. Francis P. Shepard for trilobites from British Columbia; and to 
Profs. Charles Schuchert, W. H. Twenhofel, and Carl O. Dunbar for 
the use of material from Newfoundland. 



bulletin: museum of comparative zoology. 



HYPOPARIA Beecher. 
Agnostidae McCoy. 

The Xormanskill contains a few species of this typically Camljrian 
family, two of the forms, one in Newfoundland and one in Virginia, 
being locally rather abimdant. 

In describing an agnostid, one is in a somewhat embarrassing posi- 
tion, for recently the question has arisen as to whether the shield 
commonly called the pygidium is not in reality the cephalon. As a 
preliminary to the description of the species it is necessary to discuss 
that point. 

In his article on an Outline of a Natural Classification of the Trilobites 
(Amer. journ. sci., 1897, ser. 4, 3, p. 183), Professor Beecher stated 
that under favorable conditions of preserxation the agnostids show on 
the ventral surface of the cephalon, "a distinct plate, separated from 
the cranidium by a suture," which "can be compared only with the 
free cheeks of other trilobites." 

Beecher did not figure this plate, nor did he state on what species 
he had seen it, but mentioned having studied the collections in the 
Museum of Comparative Zoology. On examination of the collection 
in this Museum, 1 also found the plate on the ventral side of some 
agnostids as described by Beecher, but the shield which carries it is 
the one considered by all palaeontologists as the pygidium. The 
question therefore has arisen as to which shield in the agnostids really 
is to be regarded as the cephalon. 

Before taking up the argument it will be well to describe this plate 
in the various species in which it can be seen. 

Agnostus nudus (Bey rich). 

Plate 1, fig. 1. 

Battus nudus Beyrich, Ueber einige bohmische trilobiten, 1845, p. 46, pi., 

fig. 20. 
Agnostus nudus Barrande, Syst. Silur. Boheme, 1852, 1, p. 903, pi. 49. 

This is one of the smooth agnostids (Phalacroma of Corda). The 
shield usually called the cephalon is quite smooth and evenly convex, 
without markings except for a concentric line a short distance from the 
margin which on exfoliated specimens delimits the doublure. There 
is no suggestion of a neck-furrow, but at the sides are a couple of 



RAYMOND: ORDOVICIAN TRILOBITES. 5 

oblique furrows, demarking regions overlapped by the ends of the 
thoracic segments when the animal is enrolled. 

The other shield, usually called the pygidiiun, is evenly convex in 
the central portion, but has a relati\ely wide border separated from 
the convex bod\' by a rather deep furrow. It is on this border that 
the sutures and ventral plate are to be seen. The specimens are casts 
of the interior of the shield, and, when perfect, show no trace of the 
structures mentioned. The cast of the interior of the doublure is, 
however, thin and fragile, and either breaks away naturally or can be 
flaked off with a fine needle. When it is removed, there is revealed a 
pair of clean-cut sutures which unite on the median line at the front 
and run backward just within the outer margin, thus cutting off a 
yoke-shaped plate within the sutures. The plate is rather wide at the 
front, but tapers to points on either side, though it extends the whole 
length of the shield. 

In spite of the fact that this plate occurs under what has been called 
the pygidium, it is impossible, on seeing it and its sutures, to think of 
it as anything else than an epistomal plate. Single shields of this 
species are of large size for agnostids and so show the plate and the 
sutures especially well. One shield is (15 mm. long, 5.5 mm. wide, and 
the epistoma is 1 mm. wide at the front. Other shields showing it well 
are 5 mm., 5.5 mm., and 6 mm. long. The specimens are from the 
Middle Cambrian at Teirovic and Slap, near Skrey, Bohemia. The 
one figured is M. C. Z. 1,686. 



Agnostus integer (Bey rich). 

Battus integer Beyrich, Ueber einige bohmische trilobiten, 1845, p. 44, pi., 

fig. 19. 
Agnostus integer Barrande, Syst. Sihir. Boheme, 1852, 1, p. 900, pi. 49. 

This seems to be the most common of Bohemian agnostids, and the 
M. C. Z. collection contains a large number of specimens, very many 
of which show the sutures and ventral plate on the shield called the 
pygidium. In this species these structures are actually so obvious 
that Barrande has represented them in one of his figures (Plate 49, 
fig. 5b) though he does not mention them in the text. 

This species (the type of Corda's Peronopsis) is of a very different 
configuration from Aguostus uudiis, the axial lobe being developed on 
both shields. The one usually called the pygiflium looks more like a 
cephalon than the other, as the median lobe is pointed, and in well- 



6 bulletin: museum of comparative zoology. 

preserved specimens shows three pairs of faintly impressed furrows. 
The axial lobe of the other shield, called the cephalon b\- authors, has 
a single cross-furrow and a pair of basal lobes. Cross-furrows are 
developed more often on pygidia than on cephala, though they are 
not unknown on the latter (Paradoxides, C'rotalocephalus, and others) 
whereas basal lobes are much more common on glabellae than on 
axial lobes of pygidia. Some agnostids have basal lobes on both 
shields {A. pisiformis, A. fissiis, A. sidcnhladhi, etc.) so that no great 
importance can be attached to either of the above characteristics. 



Agnostus bibullatus Barrande. 
Agnostus bibullatus Barrande, Syst. Silur. Boheme, 1852, 1, p. 906, pi. 49. 

This species is rather rare, and there are only a few specimens in the 
collection. The ventral structures occur on what has been called the 
p\gidium, but further than to satisfy myself of their presence 1 have 
not gone, owing to my reluctance to mar the little material we have. 
The general appearance of this species is much like .1. nudiis and the 
shield usually called the pygidium has more the appearance of a 
cephalon than the one usually so designated. It has a median tu- 
bercle, and dorsal and glal)ellar furrows, whereas the other shield is 
featureless. The specimens are all from the Middle Cambrian at 
Teirovic, Bohemia. 



Agnostus rex Barrande. 
Agnostus rex Barrande, Syst. Silur. Boheme, 1852, 1, p. 908, pi. 49. 

This is another large agnostid, and differs considerabl\' from the 
other species. It is the type of Corda's genus Condylopyge. The 
sutures are well shown on se\eral specimens of the shield usually 
called the pygidium. The ventral plate appears to be very narrow 
and is satisfactorily seen on only one specimen. On this the sutures 
meet just inside the margin and swing somewhat inward so that they 
are farther from the margin at the sides. The ventral plate, every- 
where narrow, is widest at the front. This shield is 5.5 mm. long, 
5.5 mm. wide, and the \-entral plate is .25 mm. wide at the front. 

The specimens are from the Middle Cambrian at Teirovic and Skrey, 
Bohemia. 



RAYMOND: ORDOVICIAN TRILOBITES. / 

Agnostus tardus Barrande. 
Agnostus tardus Barrande, Syst. Silur. BoMme, 1852, 1, p. 913, pi. 49. 

This species is from the Upper Ordovician of Bohemia and it is 
therefore especially interesting to find that it shows the same sort of 
sutures and ventral plate as the species from the Middle Cambrian. 
In the specimen which shows the structures best, the ventral plate is 
twisted around through an arc of about .30° to the left, thus showing 
conclusively that it was free. x\s in the other species, the plate is on 
the shield usually called the pygidium, and here again that shield has 
more the appearance of a cephalon than of a pygidium. This species 
was the type of Arthrorhachis Corda. 

The specimens are from Kralovy dviir and Mt. Kosov, Bohemia. 

In addition to the species in which 1 have actually seen the plate, 
there Tiiay be mentioned a few figures in which, ha\ing become familiar 
with the appearance, it is possible to make out, more or less distinctly, 
traces of the sutures. 

Agnostus fissus Lundgren. (Lake, British Cambrian trilobites, 
pt. 1, Paleontogr. soc, 1906, 1, pi. 1, fig. 1). At the posterior end a bit 
of the trilobite is flaked off showing the suture at the margin of the 
"pygidium." 

Agnostus rotundatus Gronwall. (Lake, Loc. cit., pi. 2, fig. 3). 
This figure seems to show the suture on the left side of the " pygidium." 

Agnostus harlowi Belt. (Lake, Loc. cit., pi. 2, fig. 7). This speci- 
men appears to be flaked on the "pygidium" so as to show a large 
part of the ventral plate. 

Agnostus dux Callaway. (Lake, Loc. cit., pi. 2, fig. 19). This 
specimen appears to show a part of the suture on the left side of the 
"pygidium" and is in such a condition that a little flaking off of the 
cast of the interior of the doublure would probably reveal the whole 
plate. 

Previous Opinions. Barrande has giv^en a list of the references 
to Agnostus down to 1852 and 1 have looked over most of them, as the 
M. C. Z. fortunately possesses nearly all the works referred to. So 
far as has been learned, the first person to figure an Agnostus was 
Magni Bromell, M.D., who published several articles on the fossils 
and rocks of Sweden in the Acta Literaria Sveciae, 1725-1729. Neither 
his description nor that of W ilckens (1768), Linne (1768), nor Modeer 
(1785) have any scientific value, though the specific name of Agnostus 
pisiformis is credited by courtesy to Linne, thanks to Wahlenburg, to 



8 bulletin: museum of comparative zoology. 

whom Barrande credits all references before 1821. Wahlenburg gave 
the first description, and, for his time, a relatively accurate figure of 
Agnostus pisiformis. Though he saw no complete specimens, he 
noted that there were two kinds of shields in the "Alum" shales of 
Sweden, and he considered one the head and the other the tail. The 
specimen he figured as the head would hardly be recognized as belong- 
ing to Agnostus pisiformis, but that called a tail is evidently the shield 
which Angelin and later authors have considered the head, the large 
basal lobes and the median longitudinal furrow back of the axial lobe 
being clearly shown. After Wahlenburg came Brongniart (1822) 
who founded Agnostus with pisiformis as the t^pe. He gave a better 
figure than had previously appeared, but considered the truncated end 
of each shield the front, and the head and abdomen different varieties 
of the same species. Schlotheim (Nachtr. petrefactenkunde, 1823) 
believed that the status of Agnostus was very doubtful in his time, but 
considering the spines of some forms of A. pisiformis to be articulated 
like the antennae of Acarus, he denominated the spinose end the 
anterior. 

Dalman (Svenska vet.-akad. Handl., 1826, p. 226) agreed with 
Wahlenburg in considering the shield which bears a furrow back of the 
axial lobe the pygidium, but none of the writers up to this date had 
any very convincing evidence for his beliefs. 

Bronn (Lethaea geogn., 1835, p. 123, pi. 9, fig. 20) and Hisinger 
(Lethaea Suec, 1837, p. 19, pi. 4, fig. 567) merely follow Dalman, and 
therefore make the same designation of head and pygidium. 

Milne-Edwards (Crustacea, 1840, 3, p. 347) was the first to adopt 
the present method of naming the anterior and posterior shields, 
reversing the procedure of all who had preceded him. Although he 
figured them in the same position as was done by Dalman and others, 
he stated that "the one of them which is the larger and shows a 
median line back of the median lobe seems to be the cephalic shield, 
and that which does not show this line seems to be the abdominal 
shield." 

Burmeister (Die organization der trilobiten, 1843, p. 56) at first 
thought that the shells of Agnostus represented the young of various 
other trilobites, and he called them all head-shields. After the 
publication of Beyrich's paper describing an entire specimen, he 
adopted that author's ^•iew as to which was cephalon and which 
pygidium, thus coming into agreement with Milne-Edwards. In his 
text and explanation of plates however, he makes contradictory 
statements. 



RAYMOND: ORDOVICIAN TRILOBITES. 9 

The first entire agnostid to be found was a specimen of Agnostus 
inieger, obtained in Bohemia and described by Beyrich. He says 
(translation): — 

Since in this genus neither ej'es nor facial suture are present, only the form 
of the axial lobe can give information as to which shield is head and which 
pygidium. In that shield which I hold to be head, one sees a deep cross-furrow 
near the anterior end of the glabella. Its position corresponds to the united 
anterior lateral furrows of other trilobites, which here, as often happens, are 
joined to each other in one furrow. The part in front of this furrow is the 
"Stirn" [frontal lobe] of the glabella. In B. pisiformis still another furrow 
runs from the middle of the frontal lobe to the bordering furrow. This I will 
call the " Stirnfurche." 

After Beyrich's time the question of which shiekl was cephalon and 
which pygidium seems to have been considered settled, for later 
authors, with the exception of Barrande, do not discuss the matter. 

Hawle and Corda (Prodrom. mon. Bohm. tril., 1847, pi. 3) were 
quite haphazard in their orientation of specimens, though frorn their 
figures of the types of Phalacroma, Condylopyge, and Lejopyge one 
would infer that they depended upon the median tubercle to indicate 
the head, and all their "Battoides" (Arthrorachis, Battus, Peronopsis, 
and Pleuroctenium) are arranged with the spines pointing backward. 

Angelin described and figured twehe species from Sweden, many of 
them from entire specimens, without discussing the method of orienta- 
tion, merely following Beyrich. 

Barrande (1852, 1, p. 494-495) was the first to give a real and 
logical reason for the orientation he adopted, and his remarks follow 
(translation): — 

If one considers a complete individual, one may easily let himself be de- 
ceived on the normal direction, for this reason, that the thoracic segments are 
ordinarily concave toward the front, that is to say, they curve in a direction 
opposite to that observed in almost all other trilobites. One escapes this 
error, in cases where the species is ornamented with spines, either on the 
cephalon or pygidium, as in ^. granulaius, for the direction of these ornaments 
indicates that of the body. In the absence of these signs, and when one has 
before him only isolated fragments, one may recognize the pygidiuin because 
it bears on its anterior margin the knees for articulation, which are lacking on 
the posterior margin of the head. It requires some care not to confound the 
knees of which we speak, with the elevated border which one finds at the front 
of the pygidium, or the occipital ring at the back of the head. 

The important point in this is, of course, that which relates to the 
articulation of the segments. In all trilobites, so far as 1 know, the 



10 bulletin: museum of comparative zoology. 

front of each segment is overlapped by the posterior portion of the 
segment before it, and the cephalon laps o\'er and the pygidium under, 
the adjacent segment. When agnostids are oriented as is the custom 
set by Milne-Edwards, Beyrich, and Barrande, the segments overlap 
one another in the same way as in all other trilobites, which is a strong 
argument for the correctness of their method. 

Now that a plate has been found on the lower side of what is, in this 
orientation, the pygidium, it is necessar;\' to take one of two positions. 
Either this plate is an extra plate of the pygidium, or the orientation 
adopted by practically all authors since Milne-Edwards is wrong, and 
all have been calling the cephalon the pygidium. The first possibility 
simply cannot be discussed, for nowhere in the whole class of trilobites 
has there ever been seen an extra plate on the x'entral side of the py- 
gidium; there is no reason to expect one; nor can one conceive how 
one could be formed. The under side of the doublure of pygidia is 
often seen, in fact is frequently sought out and studied, since in some 
groups, as for example in the Asaphidae, the extent of the doublure is 
of classificatory \'alue, so that if a suture and plate were present on the 
pygidia of other trilobites the fact would be apt to be known. 

There are numerous reasons, aside from the ventral plate, for 
believing that the agnostids should be oriented in a position the 
reverse from the customary one. If Plate 6 of Angelin's Palaeontologia 
Scandinavica is re\ersed, 1 think the figures will appear more natural. 
In the accepted position the tip of the pleura of the thoracic segments 
and the pleural furrows point forward; in the reversed position they 
point backward, as in all other trilobites. In the accepted position 
every species has a tubercle on the median line of the pygidium; in 
the reversed position this would be on the cephalon, where it usually 
occurs. In the accepted position the cephalon is in general more 
smooth than the pygidium; in the reversed position the p,^'gidium is 
the smoother, as is the rule among trilobites. In the accepted posi- 
tion the glabella is more smooth than the axial lobe of the " p\'gidium," 
a condition practically unknown among other trilobites; in the re- 
versed position the axial lobe of the anterior shield usually shows three 
pairs of furrows, the normal number of glabellar furrows in most 
trilobites. 

Turning to Plate 49 of Barrande's work (Syst. Silur. Boheme, 1852, 
1) it will be noted that the above remarks hold equally well with 
regard to the species described by him. A difficult,\' arises, however, 
in regard to the spines of Agnostus granulatus. One of the reasons for 
the conventional orientation has been that spines in trilobites normally 



RAYMOND: ORDOVICIAN TRILOBITES. 11 

point backward, and the p\'gidium is apt to be more spinose than the 
cephalon. Exceptions to these rules are, howe\'er, rather numerous. 
x\ll the Raphiophoridae ^•iolate both, Narious species of the Proetidae, 
Phacopidae, and Odontopleuridae have numerous forward-pointing 
spines on the front of the cephalon, and even such a thing as a trilobite 
with forward -pointing spines on the thorax is known, though it is not 
a common feature. Spines of any length are exceedingly rare among 
the Agnostidae, and the short stubby spines usually seen could as well 
belong to the cephalon as the pygidium. The only important argu- 
ment against reversing the usual orientation of the agnostids seems to 
be the way in which the segments overlap one another, and, it must be 
confessed, this seems a fundamental feature. It is, however, possible 
to conceive that the ordinary mode of progression of the agnostids was 
backward and that this direction of locomotion led to the similar 
development of the two shields and the change in the overlapping of 
the segments. It will be noted that nowhere in the Agnostidae do we 
see a nuchal spine developed, this being an impossibility for the 
cephalon, since the first segment laps over the neck-ring, and although 
such a spine might develop on the front of the pxgidium, it would 
hardly be expected. 

The preponderance of the evidence seems to be, then, in favor of 
returning to the \'iew of Wahlenberg and other early writers, and 
orienting the agnostids in a position which is exactly the reverse of the 
one at present in general vogue. 

Since the above was written, the writer has described Agnoshis 
insiidiis (Proc. Boston soc. nat. hist., 1924, 37, p. 393, pi. 12, fig. 2). 
When placed in proper light under a binocular microscope, the speci- 
men appears to show traces of facial sutures meeting at the front on 
the dorsal side of the shield bearing the marginal spines, and usually 
designated as the pygidium. 

Arthrorhachinae Raymond. 

Arthrorhachis galea (Billings). 

Agnostus galba Billings, Pal. foss. Canada, 1865, 1, p. 297, fig. 288. Vogdes, 
Amer. geol., 1892, 9, p. 395, pi. 9, fig. 6. Bassler, Bull. 2a, Geol. surv. 
Virginia, 1909, p. Ill, fig. 10, 2-5 (from Billings). 

The short glabella and short axial lobe of the pygidium make this a 
typical Arthrorhachis, very similar to the type of the genus. 

Measurements: — Billings says of his specimens: "Length of head 
and pygidium from 1 to 2 lines each" [2 to 4 nun. approximately]. 



12 bulletin: museum of comparative zoology. 

The type (measurements of the figure, not the specimen) has the 
following dimensions: — Cephalon 3.75 mm. long, 4 mm. wide; glabella 
2.25 mm. long, 2 mm. wide at base; pygidium 3.5 mm. long, 4 mm. 
wide; axial lobe 2.25 mm. long, 1.5 mm. wide at middle. 

Horizon and Locality: — Billings's specimens were all from New- 
foundland, and the horizons cited are M and N at Table Head and 
Pistolet Bay and P, four miles northeast of Portland Creek. Pro- 
fessors Schuchert and Twenhofel collected typical specimens in zones 
Mo and Ni and in the Isolated limestone, all at Table Head, Nfld. 
Schuchert and Dunbar obtained one pygidium from the Cow Head 
conglomerate at Cow Head, Nfld. Bassler has reported the species 
from the Liberty Hall limestone at Lexington, Va., and from the 
Thomas farm, three miles northeast of Blacksburg, Va., where it is 
very abundant at the top of the Holston. 

1 did not find any agnostid at Lexington, but obtained many from 
the Thomas farm. These latter differ in some minor respects from 
those found in Newfoundland, and are, 1 believe, to be regarded as a 
new species. 

Arthrorhachis longicollis, sp. nov. 
Plate 1, fig. 5, 6. 

Associated with Arthrorhachis gaJha in Newfoundland, Schuchert and 
Twenhofel found a few specimens which apparently represent two 
other species of the same genus. One only of these species is repre- 
sented by cephala, whereas there are two kinds of pygidia, which 
makes it impossible to be absolutely sure of the allocation of the 
abdominal shields. 

In A. longicollis the form of the cephalon and the arrangement of 
glabellar furrows and median pustule is the same as in A. galha, but 
the portion in front of the anterior cross-furrow is longer, which results 
in the elongation of the whole glabella. The pygidium which seems 
to belong to this cephalon is similar to that of A. galha, l)ut has a small 
median tubercle at the posterior end of the axial lobe. An exfoliated 
specimen shows also dark markings which indicate four pairs of 
faintly impressed furrows at the sides of the axial lobe. A specimen 
with the test shows three pairs of very shallow lateral furrows. Both 
have a narrow longitudinal median line. The surface is minutely 
reticulated. 

That this is the pygidium which probably belongs with the above 
cephalon is indicated by the fact that this type of cephalon and 



RAYMOND: ORDOVICIAN TRILOBITES. 13 

pygidium are associated both in the Isolated Hmestone and in M at 
Table Head, Nfld., whereas the pygidium next described is found only 
in the Isolated limestone. 

Measure merits: — C'ephalon 2.5 mm. long, 2.75 mm. wide; glabella 
1.75 mm. long, 1.5 mm. wide; pygidium 3 mm. long, about 3 mm. wide 
(imperfect); the axial lobe is 1.75 mm. long. 

Horizon and Locality: — A cephalon from the Isolated limestone at 
Table Head is designated as the holotype. A pygidium from Mo at 
Table Head is figured as a paratype. Known only from these two 
occurrences in the Normanskill of Newfoundland. Types in the Yale 
University Museum. 

Arthrorhachis, sp. ind. 

A third species of Arthrorhachis is indicated by pygidia with an 
axial lobe which bears a small pustule about midway. Behind the 
pustule are a pair of shallow grooves running down into the dorsal 
furrows and outlining the posterior portion of the axial lobe. 

Measurements: — The best pygidium is 4 mm. long, and 4 mm. 
broad. The axial lobe is 2.5 mm. long, and 1.75 mm. wide at the 
middle. 

Horizon and Locality: — P;\gidia of this species have been found in 
the very fossiliferous fault-block at Table Head, Nfld., associated with 
other typical Normanskill fossils. 

Arthrorhachis elspethi, sp. nov. 
Plate 1, fig. 2-4. 

This trilobite is very closely allied to A. galba, having the same form 
and disposition of lobes and furrows, but differs in having a shorter, 
more pointed glabella, and shallower furrows. A comparison with 
Billings's figure of A. galba would lead one to suppose the outlines of 
the cephala to be very diflferent, since A. elspethi has a pair of marginal 
spines, but closer inspection shows that specimens from Newfoundland 
have these same projections. The pygidium of the new species is 
almost identical with that of A. galba. The axial lobe normally 
appears smooth, but well-preserved specimens when inspected in the 
proper light, show a pair of incomplete furrows and a very faint 
median tubercle. It has been necessary to greatly exaggerate these 
to show them in the figure. 

Measurements: — The specimens from the Thomas farm near 



14 bulletin: aiuseum of comparative zoology. 

Blacksburg have the following proportions: — Cephalon 3 mm. long, 
3 mm. wide; glabella 1.25 mm. long, 1.25 mm. wide at base; pygidium 
3.5 mm. long, 3.75 mm. wide; axial lobe 2 mm. long, 1.75 mm. wide 
at the middle. 

Horizon and Locality: — This species is abundant in the highest 
strata of the Holston limestone on the Thomas farm, three miles north- 
east of Blacksburg, Va. ; six specimens have been found in a limestone 
near the middle of the Athens, in a railroad cutting one mile south of 
Otes, north of BuUsgap, Tenn., and three in the Athens two miles 
north of Athens, Tenn. The cotypes (M. C. Z. 1,626, 1,627) are from 
the Thomas farm. 

CoxDYLOPYGiNAE Raymond. 

Peronopsis munda, sp. nov. 

Plate 1, fig. 7. 

Cephalon and thorax unknown. 

Pygidium narrow, subquadrate, highly vaulted, surrounded by a 
narrow convex border. Axial lobe narrow, very convex, crossed by a 
single transverse furrow. In front of the furrow there is an ill-defined 
elevation suggestive of a large median pustule. Pleural lobes narrow, 
convex, and smooth. The accessory lobes at the anterior end of the 
axial lobe are very small. 

The narrow pygidium of this species suggests that of P. integer 
(Barrande), the type of the genus. It differs from that species, how- 
ever, in lacking radiating grooves diverging from the dorsal furrows. 
P. hidens (Meek), an l^pper Cambrian species from Ne^'ada, has the 
transverse furrow much farther forward. P. sidenhladki , which occurs 
with the Ceratopyge fauna in Europe, has the transverse furrow 
arched backward, instead of straight, and the Peronopsis which 1 
listed from the Shumardia limestone at Levis as P. sidenhladki also 
has a curved transverse furrow. 

Measurements: — Length of pygidium 2.25 mm., greatest width 
L75 mm.; length of axial lobe L5 mm.; distance from anterior 
border to transverse furrow 1 mm. 

Horizon and Locality: — The holotype (M. C. Z. 1,726) was collected 
from the Lower Ordovician in the Sinclair Canyon near Lake Winder- 
mere, southeast of Golden, B.C., by Dr. Francis P. Shepard. 



RAYMOND: ORDOVICIAN TRILOBITES. 15 

Harpedidae Corda. 

EOHARPES UNISERIALIS, Sp. nov. 

Plate 1, fig. 8, 9. 

Cephalon high, with steep sides, narrow, deepl\- concave brim and 
long slender genal spines. Glabella high and wide, with strongly 
developed basal lobes and a wide deep circumglabellar furrow, which, 
opposite the basal lobes, is expanded into deep semicircular "alar" 
depressions. The simple eyes are situated on low mounds on the 
highest points of the cheeks, and are connected to the glabella by 
short eye-lines. The sides of the cheeks are ver;\' steep, descending 
without the intervention of a cheek-roll into the narrow concave brim. 
The genal spines are longer than the central part of the cephalon, and 
at their posterior ends turn rather sharply inward. Along the deepest 
part of the brim is a single line of large pits, around which smaller pits 
are scattered irregularly. The sides and front of the cheeks are 
covered with large pits which are rather regularl,^' arranged, though 
not in perfect alignment, and the top of the cheeks outside the circum- 
glabellar furrow, has somewhat smaller ones. The glabella and the 
alar areas are smooth. 

Thorax and pygidium unknown. 

Measurements: — The most perfect cephalon is 8 mm. long on the 
median line, and 22 mm. long from the front to the tip of the genal 
spines. It is 14.5 mm. wide at the neck-ring. The glabella is 5.5 mm. 
long, and 5 mm. wide across the basal lobes. The brim is 1 .5 mm. wide 
at the sides. A larger specimen is 32 mm. long over all, 11.5 mm. long 
on the median line, and 21 mm. wide at the neck-ring. 

Among the described species of Eoharpes from the American 
Middle Ordovician, only E. dentoni (Billings) and E. ndreUuvi (Clarke) 
have as narrow a brim as E. uniserialis. E. denioni is readilv dis- 
tinguished because the glabella has a reticulate ornamentation. E. 
rntrellum is a much more closely allied species, differing chiefly in 
having a much broader cephalon, and in ha\'ing the glabella covered 
with shallow pits instead of being smooth. 

Horizo7i and Locality: — From the Kimmswick limestone at Mincke, 
St. Louis Co., Mo., where the types (M. C. Z. 1,681, 1,682) were 
collected bv Dr. D. C. Barton. 



16 bulletin: museum of comparative zoology. 

EOHARPES FRAGILIS, Sp. nov. 

Plate 1, fig. 10, 11. 

Cephalon broad, depressed, with a broad slightly concave brim 
which is extended into short genal spines. The glabella is narrow, with 
a distinct neck-furrow and two pairs of faintly defined lateral furrows. 
The alar areas are scarcely outlined and the cheeks slope gently on all 
sides into the brim. Near the base of the slope there is a slight con- 
striction and a suggestion of a cheek-roll. The simple eyes are rather 
large, situated a little back of the anterior end of the glabella, with 
which they are connected by faint eye-lines. The surface of the 
glabella and cheeks is smooth, the cheek-roll is faintly pitted, and the 
brim is covered with very small pits and very faint radiating lines. 

This species differs from Eoharpes antiquatus in having a wider brim, 
smoother surface, less conspicuous eye-lines, and in many other minor 
features. 

Eoharpes granti (Billings) is the most closely allied species, but it 
differs from that form in the presence of a faint cheek-roll, in having 
much less conspicuous radial markings on the brim, and in having the 
ocelli a little farther back. 

Measurements: — A cranidium is 15 mm. long, and 16 mm. broad at 
the neck-ring. The brim is 4.5 mm. wide at the front. 

Horizon and Locality: — Five fragmentary cephala were collected 
by Professor Dunbar from a pebble in the Cow Head conglomerate on 
Stearing Island, Nfld. The associated fossils were Hadrohybus dim- 
bari, Homotelus catactiis, and PHomerops barrandei. The types are in 
the Yale Universitv Museum. 



Eoharpes granti (Billings). 

Harpes granti Billings, Pal. foss. Canada, 1865, 1, p. 326, fig. 314. 

A single cranidium which seems to be referable to this species was 
obtained from the Cow Head conglomerate in Newfoundland. 

The important characteristics of the species appear to be the pres- 
ence of two pairs of glabellar furrows, lack of distinct alar areas at 
the base of the glabella, and presence of strongly developed radial 
markings on the brim. The central part of the cephalon is raised high 
above the brim, the slopes are steep and there is no cheek-roll. 

Measurements: — Length of cephalon, including spines, about 



RAYMOND: ORDOVICIAN TRILOBITES. 17 

35 mm., length on the median line about 15 mm., greatest width 
29 mm. Length of glabella 6.5 mm., width at base, 6 mm. 

Horizon and Locality: — Billings's original specimen was found in a 
conglomerate on lot 20, range 6 of Stanbridge, Quebec. The specimen 
from Newfoundland was from a pebble in the Cow Head conglomerate, 
at the Lower Head, Nfld., and was collected by Professors Dunbar and 
Schuchert. 

EoHARPES, spp. ind. 

The presence of Eoharpes in Virginia is attested by fragments of 
the brim found near the top of the Holston at the Thomas farm, three 
miles northeast of Blacksburg, and in the Ottosee at and two miles 
east of Fugates Hill and seven miles north of Mendota, Va. These 
fragments are too small for specific identification, but suggest a species 
with a narrow brim, like Eoharpes antiquatus (Billings). 

Dr. Bassler (Bull. 2a, Geol. surv. Virginia, 1909, p. Ill, fig. 1) has 
reported Eoharpes otfawaeiisis (Billings) from the Liberty Hall at Lex- 
ington, Va., but as the specimens are fragmentary it may turn out that 
they are not conspecific with the Chazy and Trenton form. 

In the upper, more thinly bedded, portion of the Holston in the 
railroad cutting west of the Ross Republic cjuarry, southeast of Knox- 
ville, Tenn., 1 found a nearly complete cephalon of an Eoharpes, 
which because it lacks the brim is not capable of exact identification 
or description. The glabella is badl\' worn, l)ut was evidently high 
and rather broad, with the usual basal loljes and the rounded smooth 
alar areas near its posterior end. Neither eye-lines nor ocelli are 
visible, which may, however, be due to poor preservation. The genal 
spines were apparently of about the same length as those of E. anti- 
quatus. In size, this specimen is about the same as the examples of 
E. ottaivaensis foimd in the Chazy of the Champlain Valley, and con- 
siderably larger than the average specimen of E. antiquatus. 

Harpes telleri Weller. 
Plate 6, fig. 6. 
Harpes telleri Weller, Bull. 4, Chicago acad. sci., 1907, p. 213, pi. 20, fig. 2. 

This is a form which 1 should have noticed in my article on the 
trilobites of the Silurian of Wisconsin, but the specimen was over- 
looked. 

Harpes telleri is exceedingly rare, and the slab here figured, from the 



18 bulletin: museum of comparative zoology. 

Day collection in the M. C. Z., contains the only recorded examples 
other than those in Mr. Teller's possession. Being preserved so as to 
show the under side, they present a few points of interest not exhibited 
by the type. 

The two specimens show different states of preservation. The 
smaller is the more perfect, since it retains the free cheeks (or Acntral 
plate), and it will be- noted that this makes a great difference in the 
appearance. The ventral plate is somewhat broader than the dorsal 
brim, and has attached to it a vertical band which closes the opening 
between the \entral plate and the brim. This vertical band extends 
somewhat below the ventral plate, so that it shows as a narrow rim on 
the lower side of the smaller specimen figured. Weller commented 
upon the deep furrow which bounded the inner margin of the brim of 
the type, and since that specimen appears to be a cast of the interior, 
it is probable that the deep furrow is an impression of the lower edge 
of the vertical plate. 

Harpes telleri is one of the forms with what Dr. Bather has called a 
cheek-roll, and the upper edge of the roll is outlined by a furrow, con- 
centric with the inner margin, but situated part w^ay up the slope of the 
glabellar mound and not far in front of the eyes. This is shown on 
the interior of the larger specimen figured, and it is of interest to see 
that this furrow coincides with the position of the upper edge of the 
vertical plate. This plate is then a partition which shuts off the 
anterior part of the cephalon from the area occupied by the vital 
organs, and its presence explains the cheek-roll. 

Another feature shown by these specimens is the upward twist of 
the inner margin of the genal spines some distance in front of the ends. 
This twist turns the genal spines upward so that the ventral surface is 
not flat and the upper inner margin forms a gradual slope to the neck- 
segment. This twist is present in many species of Harpes, but is not 
seen, because one seldom has the specimens exposed from the ventral 
side. 

Horizon and Locality: — The species has so far been found only in 
the Silurian in the vicinity of Milwaukee. The specimens (M. C. Z. 
1,624, 1,625) in the Day collection are from Wauwatosa, Wis. 

Harpides concentricus Billings. 
Harpides concentricus BiWings, Pal. foss. Canada, 1865, 1, p. 282, fig. 268. 

This species remains practically unknown, but it may be worth 
recording that Professors Schuchert and Twenhofel found a small 



RAYMOND: ORDOVICIAN TRILOBITES. 19 

fragment of a brim in the fault block of the Normanskill at Table 
Head, Nfld. Billings's specimens were from the conglomerates of 
division P, northeast of Portland Creek, Nfld. 

Trinucleidae Emmrich. 

Since my previous discussion of the subdivisions of the Trinucleidae 
seems to haxe been o\erlooked or misunderstood, I will repeat here the 
reasons for using the names Tretaspis, Trinucleus, and Cryptolithus, 
as 1 did in the Zittel-Eastman Textbook of Palaeontology. 

Starting from two premises, which probably do not need further 
demonstration, namely, that the name Cr\ptolithus antedates Tri- 
nucleus and that the Trinucleidae are capable of subdivision, 1 en- 
deavored to save Trinucleus as a generic name. 

^Vlurchison, imder the caption of Trinucleus, described six species. 
The fifth of these, Trinucleus nudns, is an Amp\x, the sixth, T.f 
asaphoidcs, was referred by Salter to Ogygiocaris hiichii, and the first 
and fourth, T. caractaci and T. Uoydi, belong to Cryptolithus. 
This leaves T. fimhriatus and T. radiatus in Trinucleus, and of these I 
chose T. fimhriatus as the t\pe of the genus. Tretaspis forms an 
easily recognizable group, differing from Cryptolithus in the much 
more strongly developed glabellar furrows, the ffask-shaped glabella, 
and the presence in the adult of simple eyes and e\e-lines. Trinucleus, 
as restricted, shows the same flask-shaped glabella and glabellar 
furrows as in Tretaspis, but lacks the simple eyes and eye-lines of that 
genus, and also has the fringe marked by pits in prominent radial 
grooves, instead being arranged in concentric lines as in Tretaspis and 
Cryptolithus. More recently (.Amer. journ. sci., 1917, ser. 4, 43, p. 
204), 1 have suggested another genus, Trinucleoides, to include the 
primitive T. nussi of Barrande, which has an exceedingly simple 
fringe and an elongate spine on the glabella. 

Trinucleoides Raymond. Fringe narrow, with onl\- one row of 
large pits. Glabellar furrows so modified as to isolate a pair of large 
lateral lobes. Glabella with long erect median spine. Simple eyes 
absent. Type: — Trinurlrus rrussi Barrande. Lower Ordovician, 
Bohemia. 

Tretaspis McCoy. Fringe marked In- concentric rows of pits. 
Glabella flask shaped, with three pairs of furrows. Simple eyes 
present. Type: — Asaphus scticornis Hisinger. Lower, Middle, and 
Upper Ordovician, cosmopolitan. 

Trinucleus Murchison. Fringe marked by pits in radial furrows. 



20 bulletin: museum of comparative zoology. 

Glabella flask shaped, with three pairs of furrows. Simple eyes 
absent. Type: — Trhmclens fimbriatvs ^lurchiaon. Middle Ordovi- 
cian, Scandinavia, Great Britain, and eastern North America. 

Cryptolithus Green. Fringe marked by pits in concentric rows. 
Glabella obovate, furrows indicated only by faint indentations or 
spots. Simple eyes absent in the adult. Type: — Cryptolithus 
tcssellatus Green. Middle and Upper Ordovician, cosmopolitan. 

Trinucleus acervulcsus Raymond. 
Plate 1, fig. 18. 
Trinucleus acervulosus Raymond, Bull. M. C. Z., 1920, 64, p. 273. 

Entire test flattened, subcircular in outline, twice as wide as long, 
with a narrow fringe. Glabella flask shaped, narrow, bulbous in 
front, constricted to a narrow, low neck behind. There are three 
pairs of glabellar furrows besides the neck-furrow, two pairs showing as 
deep pits in the neck and one pair as small pits at the sides back of the 
middle of the bulb. On the middle of the bulb is a small tubercle. 
Fixed cheeks evenly convex, without eye-lines or eyes in all specimens 
seen. One specimen shows traces of genal caeca running out nearly 
to the genal angle. Surface of glabella and cheeks reticulate. Fringe 
narrow, marked by radiating grooves separated by rounded ridges of 
about the same width. In the bottom of each groove are two pits, 
the anterior of which is the larger. At the genal angles the fringe 
widens and is marked by a number of irregularly placed, small pits. 
No specimen has been seen which retains genal spines, but they 
were undoubtedly present, as there is a long spine on one of the 
slabs. 

Thorax of six narrow segments of the usual form in the family. 

Pygidium a little more than twice as wide as long, somewhat angular 
in outline on the posterior margin, nearly flat, with an abruptly de- 
flected smooth border. Axial lobe narrow, not strongl;)- elevatetl, 
with twelve to fifteen narrow rings separated by narrow, sharp fur- 
rows. Pleural lobes flat, with eight or nine pairs of ribs, each bearing 
a broad deep furrow. 

Measurements: — The holotype (M. G. Z. 1,592) is 19 mm. long, 
19 mm. wide at the genal angles; the cephalon 8 mm. long; thorax 5, 
and pygidium (i mm. long. The bulb of the glabella is 5 mm. wide; 
the axial lobe of thorax 3 mm. wide; the pygidium 1.3 mm. wide. The 
fringe is 1 mm. wide, and there are twelve grooves m 5 mm. Another 



RAYMOND: ORDOVICIAN TRILOBITES. 21 

specimen is 19 mm. long, and IS mm. wide, and a third 12.5 mm. long, 
and 12 mm. wide. 

This species, the first American representative of the genus to be 
known from complete specimens, is more like Tri nucleus diadcmaia 
(Ruedemann) than any other allied form. Ruedemann's species from 
the boulders at Rysedorph Hill was described from an incomplete 
cephalon, so that detailed comparison is not possible. It would 
appear, however, that T. acervulosus has a narrower fringe and less 
prominent glabella than specimens from the New York. 

Trinucleus fimhriatus Murchison, the type of the genus as restricted, 
is very similar to T. acervulosus, but differs in having more pits in the 
fringe, particularly at the genal angles. T. fimhriaius and T. acervu- 
losus are probably from about the same horizon (Llandeilo). 

Formation and LocaJiiij: — Numerous specimens of this species have 
been collected by Prof. Roy Holden from the Athens shale three miles 
northeast of Blacksburg, Va. 1 have found fragments which appear 
to belong to this species in the Athens two miles north of Athens, Tenn. 



Cryptolithus, sp. ind. 

A single fragment of the cheek and fringe of a small specimen indi- 
cates the presence of this genus in the Athens in the Catawba Valley. 
The cheek is smooth, and the fringe shows three rows of small pits, 
concentrically arranged. Repeated searches in this locality have 
failed to reveal additional specimens, but this is sufficient to demon- 
strate the presence of the genus in the Athens. 



DiONiDEiDAE Raymond. 

Dionideidae Raymond, Bull. M. C. Z., 1920, 64, p. 274. 

Dionideae Giirich, Centrabl. min. geol. pal., 1907, p. 135 {nomen nvdum). 

Dionide has usually been placed with Trinucleus and Ampyx in the 
Trinudeidae. The structure is, however, not in accord with either 
of those genera and since they have been separated, Dionide can not 
logically be placed in either family. The free cheeks are ventral like 
those of the Trinudeidae, but the cephalon does not have a regularly 
pitted brim and the pygidium is very large. The family may be diag- 
nosed as follows : ■ — 

Isopygous hypoparia with six segments in the thorax and both 
shields large. Free cheeks ventral except for the genal spines. Sur- 



22 bulletin: museum of comparative zoology. 

face of cephalon irregularlx' pitted. Hypostoma short, rounded, 
tuberculated. 

One genus, Dionide Barrande. Ordovician, Europe and North 
America. 

Dionide Barrande. 

Dione Barrande {non Dione Hiibner 1816), Not. prelim., 1846, p. 32. 
Dionide Barrande, Neues jahrb., 1847, 4, p. 391. 
Polytomurus Corda, Prodrom einer mon., 1847, p. 37. 

Although known to have a fair specific representation in the British 
Isles, and to be represented by a single species in Sweden and Bohemia, 
this strictl\- Ordo\'ician genus was first reported from America in 1920. 
To differentiate satisfactoril;\' the similar Endymionia, it became 
necessary to restudy the tApical species, Dionide formosa Barrande, of 
which the M. C. Z. fortunately possessed a considerable number of 
specimens. Careful study indicates the presence of four, rather than 
one species in Bohemia, and those will be re\'iewed in connection with 
the ones disco\ered h\ Professor Holden in Mrtrinia. 



' f-'* 



Dionide Formosa Barrande. 

Dione formosa Barrande, Not. prelim., 1846, p. 32. 

Dionide for mosa Barrande, Neues jahrb., 1847, 4, p. 391. 

Polytomurus formosus Corda, Prodrom einer mon., 1847, p. 37, pi. 3, fig. 16. 

Dionide formosa Barrande, Syst. Silur. Boheme, 1852, 1, p. 641, pi. 42, fig. 

24, 28 {non 2b, 27). 

This species, as exemplified by the large complete specimens with 
long genal spines is too well known to require a formal description, but 
it should be restricted to the forms with suljtriangular p\-gidia which 
have 20-25 rings on the axial lobe, and aliout sixteen pairs of ribs on 
the pleural lobes. The furrows separating the rings on the axial lobe 
are narrow and very deep, and their course is doubl\' bowed, being 
convex forward at the center, and concave forward at the sides. The 
cephalon presents few distincti\'e characteristics. The glabella ap- 
pears to be somewhat less swollen than that of the other Bohemian 
species, and has the glabellar furrows but not the spine, of the adult 
D. speciosa. The nervures originate farther forward in this species 
than in either D. jubata or D. speciosa and the long flat genal spines of 
the free cheeks are of course characteristic. 

It will assist in distinguishing among three of the Bohemian species 
to point out that in D. formosa the pygidium is longer than the 



RAYMOND: ORDOVICIAN TRILOBITES. 23 

cephalon, in D. speciosa the shields are equal in length, and in D. juhata 
the p\gidium is shorter than the cephalon. 

Measurements: — One specimen is about 29 nnn. long, and 24.5 mm. 
wide; the cephalon is 9.5 mm. long; the thorax 9.5 mm.; and the 
pygidium 11 mm. Another is 16.5 mm. long, 16 mm. wide; cephalon 
5.5 mm. long; thorax 5.5 mm.; and pygidium 6 mm. long. 

Horizon and Locality: — This species is represented in the Schary 
collection by specimens from Wince, Trubin, and Hredle, near Zebrak, 
Bohemia. All these from stage D-d;i. 

DiONiDE SPECIOSA (Corda). 

Polytomurus speciosus Corda, Prodrom einer mon., 1847, p. 37. 

Dionide formosa Barrande {pars), Syst. Silur. Boheme, 1852, 1, pi. 42, fig. 

25-27 {non 24:, 28). 
Dionide formosa Barrande, Syst. Silur. Boheme Suppl., 1872, p. 50, pi. 1, fig. 

18a, b. 
Dionide formosa Novak, Beitr. pal. osterreich-imgarns u. orients, 1883, p. 30, 

pi. 8, fig. 17a, b. 

Specimens small for the genus, oval in outline, the breadth at the 
back of the cephalon nearly equal to the length. The cephalon and 
pygidium are equal in length and the thorax is slightly shorter than 
either shield. 

The cephalon is two and one half times wider than long, regularly 
rounded in outline, with the genal angles extended into spines which in 
the adult reach back as far as the posterior end of the pygidium; in 
young specimens 6 mm. long, the spines extend as far back as those of 
D. formosa, i.e., to a distance beyond the end of the pygidium equal to 
about three fourths the length of the body. The cranidium makes up 
nearly the entire cephalon, the free cheeks appearing on the dorsal 
surface only in the genal spines, as usual in the genus. The glabella is 
raised high above the fixed cheeks, and separated from them by a 
narrow circumglabellar furrow. About half-way to the front of the 
head is a short lateral glabellar furrow on either side, and at the back 
there are two deep narrow furrows which rini straight forward from 
the neck-furrow. Almost exactly in the middle of the top of the 
glabella there is a small pustule, and directly back of it and close to it, 
the base of a considerably larger spine. Otherwise the surface of the 
glabella is smooth. 

The fixed cheeks are convex, the surface finely reticulated with small 
pits and on each side two or three branching genal caeca extend from 



24 bulletin: museum of comparative zoology. 

the dorsal furrows across the cheeks to the neighborhood of the genal 
angles. There is a very narrow smooth border around the anterior 
and lateral margins of the cephalon, and just within it a row of small 
but deep pits. The neck-furrow is narrow but clear cut, and the 
neck-ring narrow and smooth. 

Young specimens differ from the adult in having a cross-furrow on 
the glabella, connecting the anterior ends of the posterior glabellar 
furrows, and showing a pair of curved pits ahead of these, indicating 
the position of the next pair of furrows. Some specimens showing these 
glabellar furrows have three and others six thoracic segments and the 
length is from 3.5 to 6 mm. 

The hypostoma has been figured by Barrande. It is large, covering 
practically the whole of the region below the glabella. The surface is 
gently convex, the oval body separated by a furrow from the large 
wings. On the body are a number of low rounded pustules. 

The thorax consists of six segments, the first of which is broader and 
more strongly marked than the succeeding ones. The axial lobe is 
narrow, convex, the pleural lobes flat on top, deflected toward the 
outer ends of the segments. On the pleural portions of the first seg- 
ment the furrows are diagonal, rather wide, and deeply impressed, but 
on the posterior ones they are narrow and more nearly parallel to the 
anterior edge of the segment. On the axial lobe also there are diagonal 
grooves on each ring, which cut off small triangular areas near the 
dorsal furrows. 

The pygidium is nearly semicircular, being almost twice as wide as 
long. The axial lobe is narrow, convex, and has from 10-15 rings, 
which are especially closely crowded together at the posterior end. 
The pleural lobes have from 10-12 pairs of ribs, each with a broad 
diagonal furrow which is more conspicuous than the very narrow 
horizontal grooves between them. All furrows extend out to the very 
edge of the pygidium. 

Measurements: — One specimen is 11.5 mm. long, and 10 mm. wide; 
the cephalon is 4 mm. long; thorax 3.5 mm. long; and pygidium 4 mm. 
long. Another is 18 mm. long, and 15 mm. wide; the cephalon is 6.5 
mm. long; thorax 5.5 mm.; and pygidium 6 mm. long. 

Corda pointed out two of the salient characteristics of this species 
in his original description, namely, the rounded pygidium and the 
relatively small number of rings on the axial lobe of that shield. 
Barrande, however, preferred to consider it a wide form of I), formosa, 
but evidently was not struck by the fact that all the specimens of the 
long form occurred in zone D— da, and all the wide ones in D— ds. 



RAYMOND: ORDOVICIAN TRILOBITES. 25 

Corda was not quite correct in stating that the rings of the axial lobe 
do not cross the middle, though the bounding groo\es are decidedly 
weaker there, and there are conspicuous pits in the furrows on either 
side of the nieflian line. The bowing of these furrows is not nearly as 
prominent as in D. fonnosa. 

The most characteristic feature of the cephalon is the presence of a 
large spine on the glabella, back of the median pustule. The actual 
spine has not been seen, but the large base, which always presents a 
fractured surface, is sufficient evidence of its presence. Corda indi- 
cated a long spine on his figure of D. formosa, but placed it on the 
median tubercle, and not in the position of the spine of D. speciosa. 

The presence of the glabellar spine and the rounded pygidium with 
relatively few rings and ribs distinguish this species from D. formosa. 
To D. juhata it is much more closely allied, differing from it principally 
by the presence of the glabellar spine. 

Horizon and Locality: — All the specimens in the Schary collection 
are from stage D — ds, the highest zone of the Ordovician in Bohemia, 
and with one exception, they are from Leiskow, near Malkow. The 
other specimen is a large one from Mount Kosov. Corda stated that 
his specimens came from near Beraun, which is some distance north- 
east of Leiskow, and Novak recorded it (under the name of D. formosa) 
from Leiskow, as did Barrande under the same name in the Supplement. 

DiONIDE JUBATA, Sp. nOV. 

Plate 1, fig. 12, 13. 

Specimens small for the genus, oval to subcircular in outline, about 
as broad as long. The cephalon is slightly longer than the pygidium, 
and the thorax slightly shorter than either shield, the proportions being 
about as 11:8: 10. 

The cephalon is about two and one half times as wide as long, the 
broad bulbous glabella standing high abo^•e the rather flat cheeks. 
The glabella shows no lateral glabellar furrows, but two furrows 
running directly forward from the neck-furrow make small indenta- 
tions at the back. Several specimens show a rather faint forward 
prolongation of these furrows, producing a broad median ridge, but 
whether this is natural or the result of pressure can not be satisfactorily 
determined. Some show a trace of lateral furrows in the sudden 
broadening of the anterior portion of the glabella. The median 
pustule is rather prominent on the otherwise smooth surface, and back 
of it there is a small bulge, which when broken or distorted, suggests 



26 bulletin: museum of comparative zoology. 

the spine-base of D. spcciosa. The cheeks are entirely covered with 
irregularly arranged pits and are crossed by the branching genal caeca. 
Long genal spines represent the free cheeks. These spines are not 
complete in any specimens studied, but evidently extended far back. 
Anterior border and neck-ring narrow and smooth, the border being an 
elevated wire-like rim. 

Thorax of six segments, and apparently in all respects like that of 
D. speciosa, except that the first segment is a little less conspicuously 
different from the remaining ones. 

Pygidium semicircular, twice as wide as long, with 10-12 rings on 
the axial and 8-10 pairs of ribs on the pleural lobes. The grooves 
between the segments are so faintly marked, and the diagonal furrows 
on them so deep, that the ribs are structurally made up of halves of 
adjacent segments, rather than from segments. This same fact is 
true of most other trilobites, but not so obviously as in this form. 

Mrasuremcnis: — One specimen is 14 mm. long and has the same 
width; the cephalon is 5.5 mm. long; the thorax 4 mm., and the width 
5 mm. Another has a cephalon 4 mm. long; pygidium 3.5 mm. long. 

This species is readily distinguished from D. formosa by its small 
size and its very short rounded pygidium with few rings and ribs. It 
is more like D. spcciosa, but the glabella lacks the spine of that species, 
and the pygidium is shorter and the ribs more rounded, with less 
prominent furrows. 

Horizon and Locality: — All the specimens in the Schar;^- collection 
are from stage D— di, at Saint Benigna, Bohemia. The cotypes are 
M. C. Z. 1,629, 1,630. 

Dionide prima Kloucek. 

Dionide prima Kloucek, Bull. int. Acad. sci. Boheme, 1917, 21, p. 10. 

This species has been but briefly described, and not yet figured. It 
is said to differ from D. formosa Barrande of zones Ddi7|(3 and higher, 
in lacking the longitudinal furrows which divide the posterior part of 
the glabella into three lobes. These furrows are constant features of 
D. formosa, D. speciosa, and D. jnhata. The species is reported only 
from the lowest fossiliferous zone of D, Ddi7Q!. 

Dionide, sp. ind. 

Dionide formosa Zelizko, Bull. int. Acad. sci. Boheme, 1907, 11, pi. 1, fig. 6. 

1 have not seen this species, but if the published figure is to be 
relied upon, the anterior position of the median tubercle and the size 



RAYMOND: ORDOVICIAN TRILOBITES. 27 

and form of the cephalon prevent its reference to any described species. 
The cephalon is somewhat distorted, but even making allowance for 
that, the length is greater in proportion to the width than in D. 
formosa. The cephalon is much larger than that of any specimens of 
D. spcciosa or D. juhafa so far seen. 

Horizon and Locality: — Zelizko refers the fauna from near Rozmital, 
Bohemia, with which this specimen occurred, to tiie lower Ordovician, 
D-d,. 

DiONiDE HOLDONi Raymond. 

Plate 1, fig. 16, 17. 

Dionide holdoni Raymond, Bull. M. C. Z., 1920, 64, p. 274. 

Animal of medium size for the genus; test o\al in outline, about one 
fifth longer than wide. 

Cephalon short, al)Out three times as broad as long. Glabella 
relatively short, reaching only two thirds the length of the cephalon, 
moderately convex, smooth except for the small median tubercle and a 
larger spine-base back of it. At the sides of the glabella there are 
faint indentations of a pair of lateral furrows, and at the back a pair 
of short longitudinal ones. These latter are somewhat longer in 3'oung 
specimens than in the adults. Fixed cheeks depressed convex, covered 
with a fine network of irregular radiating branching ridges and small 
shallow pits. The two principal genal caeca originate on either side 
of the glabella just in front of the lateral furrows and run diagonall\' 
backward, reaching the neck-furrow some distance inside the genal 
angles. Those on the right cheek of one specimen not only branch, 
but in the outer part of their course, the two unite, showing conclusively 
that they are not facial sutures. The cephalon has a narrow, upturned 
rim aroimd its border, and in the concentric depression within this is a 
row of pits which are larger and deeper than the others on the cephalon. 
The neck-furrow is linear, clearly impressed, and the neck-segment 
smooth. As usual in the genus, the facial suture is marginal except at 
the genal angles, where it cuts off the spines. These latter are not 
satisfactorily preserved on any specimens, but apparently were not 
long enough to reach beyond the third thoracic segment, a very un- 
usual feature in this genus, and leading one to suspect that the speci- 
mens are incomplete in this regard. 

Thorax with six narrow segments, the first of which is a little wider 
than the succeeding ones but not differently marked. Axial lobe 
narrow, each ring showing the diagonal furrow at the sides as is usual 



28 bulletin: museum of comparative zoology. 

in the genus. The furrows on the pleural lobes divide each lateral 
portion of a segment into an anterior area which is pitted like the fixed 
cheeks, and a narrower smooth posterior part. 

The pygidium is about twice as wide as long, rounded in outline, 
with, in some cases, sufficient straightness of sides to produce a slight 
triangularity. Axial lobe narrow, with about fifteen rings, and pleural 
lobes with about twelve pairs of furrowed ribs which extend to the edge. 
Surface pitted, like that of fixed cheeks. 

Measurements: — One specimen is 15.5mm. long, 13 mm.; wide at 
the genal angles. The pygidium is 5.5 mm. long, 11.5 mm. wide; 
thorax 4.5 mm. long; cephalon, 5.5 mm. long. Another specimen is 
15 mm. long, and 12.5 mm. wide. A third specimen is 19.5 mm. long, 
and 15 mm. wide. 

A cephalon is 6 mm. long, and 18 mm. wide; distance from back to 
front of glabella, 4 mm., width of glabella 4.5 mm. 

This species is more like Dionide richardsoni Reed than any other 
known species of the genus. The likeness is emphasized particularly 
by the ornamentation of the thorax. It has, however, fewer rings 
and ribs on the pygidium, a wider cephalon, and narrower axial lobe. 
The ornamentation of the thorax and pygidium separates it from all 
other species. 

Horizon and Locality: — This species has so far been found only 
at a locality about 100 feet below the top of the Athens shale about 
three miles northeast of Blacksburg, Va., where it was collected by 
Professor Holden, for whom it is named. The associated fossils are 
typical Normanskill graptolites, brachiopods, and trilobites. Holo- 
type (M. C. Z. 1,590); paratype (M. C. Z. 1,720). 

Dioxide contrita Raymond. 
Plate 6, fig. 9. 
Dionide contrita Raymond, Bull. M. C. Z., 1920, 64, p. 276. 

This species is represented by only a single specimen, a rather poor 
pygidium to which are attached parts of two segments of the thorax. 
It would not be worthy of description were it not for the fact that it 
belongs to the group with large pygidia. 

Cephalon not yet known. 

Thorax with narrow axial lobe and short segments, the outer ends of 
which turn backward. 

Pygidium large, nearly semicircular but not quite twice as wide as 



RAYMOND: ORDOVICIAN TRILOBITES. 29 

long. Axial lobe narrow, tapering graduall\- and regularly. The last 
four millimeters of the axial lobe are broken off, but the anterior part 
shows eighteen rings, and there were apparentlx' about twent;s-four 
pairs of ribs on the pleural lobes, being especially- crowded at the 
posterior end. 

Measurements: — Length of pygidium, 14.5 mm., width al)out 24 mm. 
The axial lobe is 5 mm. wide at the front. 

Horizon and Localiti/: — The only known specimen was collected 
by the writer about 100 feet abo\'e the bottom of the Athens shale near 
the Thomas farm three miles northeast of Blacksburg, \'a. Holo- 
type (M. C. Z. 1,591). 

Raphiophoridae Angelin. 

Before proceeding to describe the representatixes of this family 
which are found in the Normanskill it will be .ser\iceable to review 
briefly the characteristics of the genera. 

Ampyx is of course the first founded and best known of them. The 
name was proposed by Dalman (Svenska vet.-akad. Handl., 1826, 
p. 252, 279) with the following description: — 

"Oculi inconspicui, nee illorum loco prominentiae potius vero im- 
pressiones detegendae. Caput magnum triangulare, glabella magna 
prominente gibbaque, baud lobata. — Truncus brevis, segmentis 
paucis (6). Pygidium distinctum, integrum." 

The only species described, which of course becomes the type, was 
Ampii-x nasutus, and the figured specimen was an entire, enrolled one 
from the red limestone (Orthoceras limestone, Megalaspis iimbata zone, 
of Beekmantown age). 

There seems never to have been any doubt about the proper identi- 
fication of Dalman's species, and figures which are in essential agree- 
ment are given by Angelin, Brogger, and Schmidt, among others. 
These descriptions and figures indicate that Ampyx nasutus is charac- 
terized by having an oval glabella which projects beyond the front of 
the cheeks and bears a spine which is directed forw^ard and upward, 
and is circular in section. The free cheeks are rather large. The 
thorax has six segments, and the pygidium has smooth pleural lobes. 

Raphiophorus was proposed by Angelin, at the time of the erection 
of the family (Pal. Scandinavica, 1854, 1, p. 80), but the genus has 
never been looked upon with favor, though it has been used by Eich- 
wald, Haupt, and Marr. Angelin separated it from Ampyx because 
the glabella was obovate instead of oval, and because there were five 
instead of six segments in the thorax. 



30 bt'lletin: museum of comparative zoology. 

The first species described by Angelin under the name Raphiophorus 
was R. setirostris, and as a complete specimen was figured, 1 propose 
that this species be designated the type of the genus. 

Raphiophorus setirostris, as figured by Angehn has a large obovate 
glaliella which extends considerabl\' beyond the front of the cheeks 
and bears a long spine which is circular in section and appears to point 
straight forward. The thorax has five segments and the pygidium 
shows distinct ribs on the pleural lobes. The facial sutures are not 
indicated, but the free cheeks are probably about as large as in Ampyx. 
This species is said to come from Region Da (Chasmops strata, about 
Middle Trenton age) in Dalecarlia, and I have found no figure later 
than Angelin 's. 

Lonchodomas was proposed by Angelin at the same time as Raphio- 
phorus, and the first species named was Lonchodomas rostratus (Sars). 
The specimen figured being complete, this may be taken as the type- 
species. Lonchodomas is clearly a distinct genus, the long prismatic 
spine into which the rather narrow glabella merges being entirely 
difl'erent from the glabellar spines of either Ampyx or Raphiophorus. 
There are five segments in the thorax, and in the type the pleural lobes 
of the pygidium have ribs. 

These three were the only genera ascribed by Angelin to the Raphio- 
phoridae, and it remains to decide whether or not Angelin was justified 
in separating Raphiophorus from Ampyx. 

There are three principal ways in which Raphiophorus differs from 
Ampyx: — There are only five segments in the thorax, instead of six; 
the glabella is said by Angelin to be obovate instead of oval; and the 
pleural lobes of the p\gidium ha\'e ribs instead of being smooth. 

Looking over the more familiar literature, without tracing out cAcry 
known species, 1 find that twenty species of Ampyx have been de- 
scribed from approximately entire specimens. Five of these have 
prismatic glabellar spines and so belong to Lonchodomas. They are: 
— Ampi/x tctraqonus Angelin, Lonchodomas rostratus (Sars), Ampyx 
portlocki Barrande, Atnpyx drummockcnsis Reed, and Ampyx macal- 
himi Salter. All of these have five segments in the thorax. Of the 
remaining fifteen species, five have six segments in the thorax, and ten 
have five segments. All of the ten species which have five segments in 
the thorax have ribs on the pleural lobes of the pygidium. These 
species are: — Raphiophorus setirostris Angelin, R. scanicus Angelin, 
Ampyx ronaulti Barrande, A. tencllus Barrande, A. gratus Barrande, 
A. macconochieri Etheridge and Nicholson, A. parvulus Forbes, 
Raphiophorus alonicnsis Marr and Nicholson, Ampyx volhortki Schmidt, 
and A. costatus Sars and Boeck. 



RAYMOND: ORDOVICIAN TRILOBITES. 31 

The species having six thoracic segments are: — Am pyx nasutiis 
Dahnan, A. omcricanus Vogdes and Safford, -]. i)H-urvus Reed, A. 
7iiidus (^Slurchison), and A. saltcri Hicks. The pygidium of Ampi/x 
inciirvus is unknown, the pygidia of A. nasidus and A. amcricanvs have 
smooth pleural lobes, the pygidium of A. saltcri has only very faint ribs, 
but the pygidium of A. nudus is covered with very strongly marked 
elevated ribs. These data indicate, as to the association of number of 
segments with ribbed pygidia, that species with fixe segments in the 
thorax always ha\e ribbed pygidia, and that species with six segments 
generally lack ribs, though they may sometimes have them. 

PVom the constanc\- with which five segments in the thorax and 
ribbed pygidia are connected, it seems well worth while to retain the 
name Raphiophorus, but it must be admitted that other characteristics 
are wanting to enable an infallible separation of Raphiophorus and 
Ampyx. The shape of the glabella, cited by Angelin, as ox'al in 
Ampyx and obovate in Raphiophorus, although more or less useful, is 
not entirely dependable. A good example of this may be seen in 
^'ogdes's (Amer. geol., 1893, 11, p. 103) grouping of the species under 
Brevifrontes, glabella o\al, and Longifrontes, glabella obovate. 
Under this classification, Ampi/.v uasutns, Raphiophorus srtirostrls, and 
Lonchodomas portlocki all fell into the same group, the Longifrontes. 

Raphiophorus semicostatus (Billings). 

Plate 1, fig. 14, 15. 

Ampyx semicostatus Billings, Pal. foss. Canada, 1865, 1, p. 295, fig. 287. 
Vogdes, Amer. geol., 1893, 11, p. 108. '^ '' 

Billings knew onl\- the pygidium of this species, which seems to be 
the most common member of the famil\- in Newfoundland. There are 
several practicalh- complete specimens in both the ]M. C. Z. and at 
Yale. 

Whole trilobite broadly oval in outline, surface depressed, with the 
dorsal furrows converging nearly uniformly backward from the front 
of the cephalon to the end of the pygidium. 

Cephalon nearly semicircular in outline, the glabella broad, expand- 
ing regularly to the place of greatest width, which is near the anterior 
end. Specimens which are not flattened show two pairs of furrows 
near the posterior enfl of the glabella, and a trace of a third pair. The 
glabellar spine is short, \ery slender, and circular in section. Fixed 
cheeks low, uniformly convex, and smooth. Free cheeks not seen, 
but e\idently very narrow, if present at all on the dorsal surface. 



32 bulletin: museum of comparative zoology. 

Thorax of five segments, the axial lobe gently arched, the pleural 
lobes flat. The grooves on the pleura are straight furrows which 
expand toward the distal ends. Those on the first segment are bowed 
forward. 

Pygidium short, with a sharply inclined striated border set at an 
angle of about 45° with the general surface. The axial lobe extends to 
the border and has four or five more or less distinct rings. The pleural 
lobes show three to four indistinct flat ribs which extend straight to the 
inclined border. 

Measureinents: — A large specimen is 10 mm. long, and 11 mm. wide 
at the back of the cephalon. The cephalon is 3.5 mm. long; the 
glabella 3.5 mm. wide. The thorax is 4 mm. long; and the axial lobe 
2.5 mm. wide at the front. The pygidium is 2.5 mm. long, and 8 mm. 
wide. A small specimen is 8.5 mm. long, and 8 mm. wide. A still 
smaller one is 4 mm. long, and 4 mm. wide. 

Horizon and Locality: — Specimens of this species from the Lingula 
shale on the east shore at Port au Port, and from the south side of St. 
Johns Island, Newfoundland, are in the M. C. Z. Schuchert and 
Twenhofel collected it from zones Mi and Ns at Table Head, Nfld, 
and zone 6 at Port au Port. It was also found by them to be espe- 
cially abundant in the Isolated limestone at Table Head. Professors 
Schuchert and Dunbar collected a large number of complete specimens 
on the shore of Port au Port Bay, one mile from the Dominion Iron 
and Steel Quarries, at Agathuna. Many of these specimens are 
crushed in such a way that the anterior spine appears to be carinate. 

Raphiophorus powelli Raymond. 
Plate 2, fig. 1, 2. 
Raphiophonis -powelli Raj^ond, Bull. M. C. Z., 1920, 64, p. 276. 

Entire test broadly oval, nearly as wide as long. Cranidium 
approximately semicircular in outline, the glabella projecting slightly 
in front of the cheeks. Glabella obovate, prominently convex, with a 
small spine directed forward and upward. At the base of the glabella 
there are two small narrow lobes, cut off by the posterior glabellar 
furrows. Fixed cheeks depressed convex. Free cheeks missing, but 
evidently narrow. Thorax with five segments, each pleuron bearing 
a deep linear, straight, median groove. P,\'gidium short and wide, 
with abruptly deflected posterior border. The pleural lobes bear two 
pairs of faintly defined ribs which curve backward to the margin. 



RAYMOND: ORDOVICIAN TRILOBITES. 33 

Measurements: — Length 10.5 mm., width 9 mm. Length cephalon 
5 mm., width 9 mm. Width glabella at front 3 mm., at back 2 mm. 
Length thorax 2.5 mm.; width axial lobe 2 mm. Length pygidium 
2.5 mm. {circa), width 8 mm. 

This species is xerx common at one horizon in the Athens in the 
Catawba \'alley, north of Salem, Va., where Prof. S. L. Powell, for 
whom it was named, has collected many approximately entire .speci- 
mens. The glabellar spine is, howe\er, \ery rarely preserved, and 
usually it is impossible to detect any trace of its former presence. Two 
other curious characteristics were possessed by this trilobite. It 
sometimes grew to normal adult size without forming more than four 
segments, as seen in Plate 2, fig. 2. In such cases the pygidium shows 
extra pairs of ribs. The presence of a pair of basal glabellar lobes is 
the other unusual feature, and one which suggests Endymionia hcllu- 
lata Savage, the t\pe of the newly established genus Ampyxina. 

This species most nearly resembles R. semicostatus, differing only in 
having a less rapidly expanding glabella, in the presence of glabellar 
lobes, and in the pygidium, which has fewer and cur\ed, instead of 
straight, ribs. 

Horizon and Locality: — Aside from the t^'pical region, the Catawba 
Valley, Va., 1 ha\'e found this species at Saltville, in the lower part of 
the Athens, and in \ellowish calcareous shales near the railroad station 
at Bullsgap, Tenn.' Holotype (M. C. Z. 1,.598); paratype, (M. C. Z. 
1,599). 

Raphiophorus quadricostatus (Emmons). 

Microdiscus quadricostatus Emmons, Amer. geology, 1855, 1, p. 116, pi. 1, 
fig. 8. Man. geol., 1860, p. 88, fig. 73. Barrande, Bull. See. geol. 
France, 1861, ser. 2, 18, p. 280, pi. 5, fig. 13. Marcou, Mem. Boston soc. 
nat. hist., 1888, 4, p. 128. 

Ampyx quadricostatus Bassler, Bull. 92, U. S. N. M., 1915, p. 42. 

Emmons, in the second part of his American Geology, created for a 
small trilobite from Augusta County, \'irginia, the new generic and 
specific names, Microdiscus quadricostatus. He stated that the speci- 
men was found in "white fragile shales, associated with minute 
molluscas and graptolites." 

The Athens (Liberty- Hall) shales of Augusta County often weather 
to a grayish or greenish white, and after becoming acquainted with 
such trilobites as Raphiophorus semicostatus and R. powelli, one cannot 
doubt that Microdiscus quadricostatus is congeneric with them. Fortu- 



34 bulletin: museum of comparative zoology. 

nately Raphiophorus antedates Microdiscus, so that the latter name 
can be discarded. Dr. Bassler was the first to recognize that the 
original of Microdiscus was really an ampycid, but from the time of 
Barrande (cited above) \arious authors have had more or less doubts 
about the propriety of the continuance in use of the generic name. In 
1912 1 made a definite proposal to discontinue its use and to substitute 
Eodiscus, a name proposed by Matthew. Even since that time, how- 
ever, Microdiscus has been in use for Lower and Middle Cambrian 
trilobites and it may interest some of those who now write Microdiscus 
Salter instead of Microdiscus Emmons, to read what Salter (Quart, 
journ. Geol. soc. London, 1864, 20, p. 237) said on his first use of the 
term: — " Dr. Emmons described, from his Taconic strata*** a minute 
form, which, from its association with Graptolites and Mollusca, 
Barrande thinks may be the young state of Trimiclcus or some such 
Lower Silurian genus. This is quite possible. But, at least, Emmons's 
figure is singularly like the small fossil here figured, and which Mr. 
Hicks finds abundant in the lower strata of the section at Porth-y- 
Rhaw. I do not feel inclined to institute a new genus for this while 
there is a probability it may be the /n/ of some larger Trilobite" 
(italics Salter's). From this it is evident that Salter used the name 
only as a makeshift until the true nature of the fossil was revealed, 
and 1 can see no reason, sentimental or otherwise, why Microdiscus 
should continue to be employed as a name for Cambrian trilobites. 

As 1 have not found specimens which can be identified with this 
species, 1 can only point out the ways in which it appears to differ 
from R. semicostatus and R. powclli. 

Emmons's brief description was as follows: "Minute, oval, middle 
lobe of the cephalic shield strongly developed; ribs of the body or 
abdomen, four; of the tail, four or five." 

As there are onW four thoracic segments, it is evident that this is an 
immature specimen, a supposition borne out by its small size, length 
only 4 mm. The possibility that the adult would show one less seg- 
ment in the pygidium must therefore be allowed, thus reducing the 
number to three or four, instead of four or five. Even this is more 
than in R. poivelli, and in that species the ribs turn backward instead 
of forward as indicated in Emmons's figure. From R. scmicostaius, 
P^mmons's species differs in having a much narrower glabella. 



RAYMOND: ORDOVICIAN TRILOBITES. 35 



Ampyx americanus Safford and Voiides 



t>^ 



Plate 2, fig. 8, 4. 

Ampyx americanus Safford and Vogdes, Proc. Acad. nat. .sc'. Phila., 18S9, 
p. 166, fig. Vogdes, Amer. geol., 1893, 11, p. 106, fig. 4. 

The original locality for this .species is at Bullsgap, Tenn., and the 
writer was fortunate enough to find a nearly complete specimen at that 
place, in the well-known outcrop under the railroad bridge east of the 
station. Although this specimen has lost the anterior spine, the base 
of it is present and shows that it was circular in section. This, with 
the presence of six segments in the thorax, proves the species to be a 
true Ampyx. Besides the whole specimen, several cranidia and 
pygidia were collected in the \dcinity of Bullsgap. 

Entire body broadly oval, but little longer than broad, with elongate 
glabellar and genal spines. 

( 'ephalon nearly semicircular in outline, the oval glabella raised 
high above the broad depressed cheeks. Free cheeks narrow, eyeless, 
extended at the angles into long genal spines each of which has on its 
upper surface a deep longitudinal depression. Glabella highly ele- 
vated, ovate in outline, enlarging toward the front. On the outer 
surface there are indications of two pairs of glabellar furrows, and the 
interior of the shell shows distinctl\' three pairs. From the front of 
the glabella projects a long, thin spine which is directed somewhat up- 
ward and is circular in section. 

The thorax consists of six segments, the pleura of which are nearly 
flat and deeply grooved. The axial lobe is a little less than one third 
the total width and not greatly elevated. 

The pygidium is nearly semicircular, with a sharply deflected border, 
flat, smooth pleural lobes, and a slightly elevated, sharply defined 
axial lobe with 12-15 transverse rings which are much less prominent 
when the shell is preserved than on exfoliated specimens. There is, of 
course, an anterior half rib on each of the pleural lobes, and two or 
three pairs of very faintly defined ribs can sometimes be seen. 

This species is characterized by the large size of some specimens and 
by the pygidium with its ringed axial and smooth pleural lobes. 

Mcasurcmcnis: — Length of a small but nearly entire specimen 
(M. C. Z. 1,677), lacking glabellar spine, 18 mm., width 17 mm.; 
length of cephalon 8 mm.; length of thorax 5 mm.; width at front 
15 mm., at back 12.5 mm.; width axial lobe at front 3.75 mm.; width 
pygidium 12 mm., length 5 mm.; width axial lobe at front 4 mm. A 



36 bulletin: museum of comparative zoology. 

somewhat imperfect cranidium is 21 mm. wide, and 15 mm. long, 
including the glabellar spine, which is 6 mm. long. An isolated py- 
gidium is 15 mm. wide, and 6.5 mm. long; the axial lobe 3.5 mm. wide 
at the front. 

Horizon and Locality: — This species seems to be quite common in 
the Athens about Bullsgap, Tenn., occurring in the thinly bedded 
limestone at the base, and in similar limestone higher in the section. 
It is not rare in the railroad cutting near Otes, north of Bullsgap. 
In Virginia 1 have found it in the quarries east of Saltville, at Chatham 
Hill north of Marion, and a single specimen in the Catawba Valley, 
north of Salem. 

Ampyx laeviusculus Billings. 
Ampyx laeviusculus Billings, Pal. foss. Canada, 1865, 1, p. 295, fig. 285. 

The following description is based on specimens from zone N3, 
Table Head, Nfld. Cephalon about one half as long as wide, trilobate, 
the glabella being as wide as either of the fixed cheeks. Glabella large, 
wide, ele\ated, widest in front of the middle, with a short small spine 
directed forward from a point high on the ele\ated front. Besides the 
neck-furrow, the glabella has two pairs of shallow glabellar furrows on 
its posterior upper surface. The dorsal furrows are rather wide. 
Fixed cheeks smoothly con\ex. Free cheeks not seen, but apparently 
very narrow and mostly ventral. 

Two segments onl^- of the thorax have been seen. They are very 
short, the axial lobe is narrow, crossed by a backward cur\ing furrow 
which divides it into two ridges, and the pleural lobe is crossed by a 
broad furrow which is parallel to the margins, and occupies practically 
all of the surface. 

The pygidium is about one half as long as wide, the axial lobe narrow, 
the pleural lobes slightly con\'ex, with an abruptly deflected border 
about the whole. At the line of fleflection there is a low hair-like ridge. 
At the anterior end of the axial lobe there is a narrow furrow outlining 
one ring, and on each pleural lobe there is a similar one. Otherwise 
the surface is smooth, though faint indications of more rings and ribs 
are seen on some specimens. 

Measurcmcnfs: — A cranidium is 4 mm. long, and 10 mm. wide; and 
the glabellar spine is 3 mm. long. The glabella is 3.5 mm. wide. 
Another cranidium is 5.25 mm. long, and 1 1 mm. wide. The first of 
two thoracic segments associated with this cranidium is .75 mm. long; 
and the axial lobe 2 mm. wide. A pygidium on the same slab with this 



RAYMOND: ORDOVICIAN TRILOBITES. 37 

is 0.5 mm. long, and ll.o mm. wiile. The axial lobe is 2 mm. wide at 
the front. Billings's figured pygidium was 4.5 mm. long, 10.5 mm. 
wide; and the axial lobe was 3 mm. wide at the front. 

This species has not, so far as I know, been reported outside New- 
foundland, but it is evidently closely allied to the Amp\x next to be 
described, a species found in the Liberty Hall and the top of the 
Holston in \'irginia. Both have smooth pygidia, but the A'irginian 
species lacks the rim on the abruptly deflected posterior border. 
Am pyx amtricanns has a wider axial lol)e in the thorax, and the axial 
lobe of the pygidium is ringed. Although the pygidiimi of this species 
is easily recognizable, 1 have not \'et found characteristics by which 
the cranidium is readil\' separated from that of other species of Ampyx 
or even from that of Raphiophorus scmicostatus. 

Horizon and Locality: — Billings's original specimens of this species, 
described from pygidia onl\', were from division N at Table Head, 
Nfld. Professors Schuchert and Twenhofel collected both pygidia 
and cephala in their zone 13, N3, at Table Head, where the species 
occurs in a fine-grained, almost black, shale. The cephalon shows 
plainly that this species is an Ampyx. 



Ampyx camurus, sp. nov. 
Plate 2, fig. 5-7. 

This species so far as known is small, with very convex glabella. 

Cranidium convex, roughly triangular, with large prominent gla- 
bella, from the anterior end of which projects a conical spine of medium 
length. The glabella rises high abo\e the cheeks, the anterior end 
projects beyond them, and the greatest width is in front of the middle. 
The posterior part of the glabella is somewhat constricted by two pairs 
of pits which represent the glabellar furrows. The spine is curved 
gently upward in one specimen, but whether this is the general rule 
cannot be stated as it seems to be broken off from all others. 

No part of the thorax has been seen. 

Pygidium short and wide, with a prominent axial lobe. Both axial 
and pleural lobes are devoid of transverse furrows except for the 
anterior one. The posterior part is sharply deflected, but there is no 
cari nation at the angle. 

Measurements; — A cranidium from Lexington, Va., is 7 mm. long 
(without the spine), and about 11 mm. "wide. The glabella is 5 mm. 
wide. A pygidium from the same locality is 4 mm. long. A cranidium 



38 bulletin: museum of comparative zoology. 

from the Thomas farm, east of Blacksburg, is 5.5 mm. long, and about 
i;i mm. wide. A pygidium is 3 mm. long, and 7.5 mm. wide. 

The species is more nearl\- allied to Am pyx lacviusculus than to any 
other American species, but can readily be recognized by the fact that 
the pygidium lacks the rim at the angle of the abruptly deflected border 
which is so well developed in that species. From A. americmnis it 
differs in lacking the rings on the axial lobe. 

Horizon and Localiti/: — This species is common in the lower beds of 
the Liberty Hall at Lexington, Va., and in the top of the Holston at the 
Thomas farm, three miles northeast of Blacksburg, Va. Cotypes 
(M. C. Z. 1,668, 1,669). 

LONCHODOMAS NORMALIS (BilHngs). 

Ampyx normalis Billings, Pal. foss. Canada, 1865, 1, p. 295, fig. 286. 
Ampyx (Lonchodomas) normalis Grabau and Shimer, N. A. index fossils, 1910, 
2, p. 259. 

There are no complete specimens in the collection, but two show a 
part of the thorax, so that a little can be added to Billings's description. 
If my identification of this species is correct, the glabella is normally a 
little wider than is indicated by Billings's figure. In the figure, the 
glabella is 3.5 mm. wide at the widest point, and the cephalon 14 mm. 
wide, the index being .25. A very well-preserved specimen from N2, 
Table Head, Xfld., has the glabella 4.5 mm. wide and the cephalon 
only 16 mm. wide, the index being .28. Measurements show the 
difference to be less than inspection would suggest, the appearance of 
greater width being due to the fact that the sides of the glabella are not 
so nearly parallel as shown in the figure. 

Cranidium roughly triangular, the glabella ele\ated high abo\'e the 
cheeks and extending a short distance beyond them. Cheeks depressed, 
convex, smooth. Free cheeks not seen, but e\idently very narrow. 
Glabella narrow at the back, expanding gradually forward and widest 
near the anterior ends of the fixed cheeks. On exfoliated specimens 
three pairs of glabellar furrows are present in front of the neck-furrow, 
and more rarely one sees a pair of deep pits in the dorsal furrows 
opposite the widest part of the glabella. On specimens with the test, 
only the posterior two pairs of furrows are \isible. The glabellar spine 
is about as long as the glabella, straight, slender, and prismatic in 
section. 

Axial loI)e of thorax narrow, a little less than one fourth the total 
width. Pleural lobes flat, with broad straight furrows. 



RAYMOND: ORDOVICIAN TRILOBITES. 39 

Pygidiuin roughl\- triangular, with a narrow, highly inclined border. 
Axial lobe narrow, with eight or ten incomplete rings indicated by 
short transverse ridges on the top. Pleural lobes smooth, except for 
the anterior furrow. 

The figure given by Billings is too long and does not show the highly 
inclined border. 

Measurements: — - A cranidium from zone N2, Table Head, Nfld., is 
9.5 mm. long, 16 mm. wide; glabella 4.5 mm. wide; glabellar spine 
9 mm. long. A pygidium from the same locality is 6 mm. long, 14 mm. 
wide; axial lobe 4 mm. wide at the front. 

The last four segments of the thorax of a specimen from zone N, at 
Table Head, are together 4 mm. long. The anterior of them (2d 
segment) is 14 mm. wide, and its axial lobe is 3.5 mm. wide. 

Ulrich has identified Lonchodomas normalis in the lower Echino- 
sphaerites zone of the Chambersburg in the Chambersburg quadrangle 
and " Ampyx n. sp. of. A. normalis and A. huUV in the Nidulites zone. 
The writer has been able to find only one species of Lonchodomas in 
the Chambersburg, either in the Chambersburg quadrangle in Penn- 
sylvania or at Strasburg, Va. This is the one described on a later 
page as Lonchodomas suhlaevis and differs from L. normalis in the large 
broad, depressed, unfurrowed glabella. 1 ha\e not yet found Loncho- 
domas in the i\thens of Virginia, but in Tennessee one finds Loncho- 
domas politus, which is somewhat like L. normalis, but has shorter 
fixed cheeks and no glabellar furrows. 

J^onchodomas halli (Billings) of the Chaz\- has very much shorter 
fixed cheeks than L. normalis, and the pleural lobes of the pygidium 
are also ribbed in that species. 

Horizon and Locality: — Billings reported this species from division 
N, Table Head and Pistolet Bay, and division P, four miles N.E. from 
Portland Creek, Nfld. 1 find it in the Schuchert and Twenhofel col- 
lection from zone M2, zone Ni, the Isolated limestone, and zone N2, 
all at Table Head, Nfld, and of Normanskill age. 



Lonchodomas politus, sp. nov. 

Plate 2, fig. 8-10. 

This species is known only from cranidia and pygidia. The glabella 
is narrow, carinate, does not expand greatl\' forward, and contracts 
abruptly into an unusually long, slender, prismatic spine. The fixed 
cheeks are short and depressed, the free cheeks probably wide. Gla- 



40 bulletin: museum of comparative zoology. 

bellar furrows represented by a pair of scars on the sides not far in 
front of the neck-furrow, and a pair of pits in the dorsal furrows oppo- 
site the widest part of the glabella. Some, but not all specimens, have 
along the axial line a narrow carina which is seen only when the shell is 
removed. 

The facial sutures truncate the cranidium lateralh, the course being 
sufficiently inward to produce a concave outline. 

Associated with the cranidia in one locality are small pygidia which 
probably belong to this species. The outline is nearly triangular, the 
posterior margin very steep, and the axial lobe wide, without rings. 
The pleural lobes have one pair of distinct furrows, limiting the usual 
anterior half rib, and two pairs more of ribs are faintly outlined. The 
surface is punctate. 

Measurements: — A cranidium from the Athens near Bullsgap is 
9 mm. wide, and 15 mm. long, including the spine, which is 9 mm. in 
length. 

A pygidium from the Athens near Athens is 2.75 mm.long,and 8 mm. 
wide; the axial lobe being 2 mm. wide at the front. 

This species resembles Lonchodomas lialli (Billings) of the Chazy, 
having short fixed cheeks and a carinate glabella. It differs in lacking 
the glabellar scars of that species, and in tapering much more rapidly 
from the glabella into the spine. The short cheeks and absence of 
glabellar furrows distinguish it from L. normalis, and the carinate 
glabella is quite different from the flat one of L. subkuvis. 

Horizon and Locality: — This species was first found in the Ottosee 
east of the quarries at Saltville, Va., and the next year near the base 
of the Athens two miles south of Bullsgap, Tenn. It is very common 
in a limestone at about the middle of the Athens, two miles northeast 
of Athens, Tenn. Holotype (M. C. Z. 1,673); paratypes (M. C. Z. 
1,671, 1,672). 

Lonchodomas sublaevis, sp. nov. 
Plate 2, fig. 11, 12. 

This species is known only from cranidia, all of which are of large 
size for the genus. 

Cranidium triangular, with broad, gently convex glabella. Fixed 
cheeks depressed, convex, triangular, extending nearly to the front of 
the glabella. Glabella only moderately convex, broadest at about the 
middle, and without glabellar furrows. In spite of the relative flatness 
of the top there is an obscure longitudinal carina. 



RAYMOND: ORDOVICIAN TRILOBITES. 41 

Mcosuremc7its: — One cranidium is about 13 mm. long, 14 mm. wide; 
and the glabella is 7 mm. wide. A smaller one is 8.5 mm. long, 13 mm. 
wide; and the glabella is 5 mm. wide. 

The short cheeks and absence of glabellar furrows distinguish this 
species from Louchodomas normatis. The cheeks are longer than in 
L. halli or L. politus, and it also has a more depressed glabella than 
either of those species. 

Horizon and Locality: — This species has so far been found onl\' in 
the Chambersburg formation. It is a rare species in the Lower 
Echinosphaerites and Xidulites zones in the section west of Marion, 
Pa., and in the Upper Echinosphaerites zone at Strasburg, \'a. Co- 
types (M. C. Z. 1,619, 1,620) from the former locality. 

Endymioniidae Raymond. 
Endijmioniidae Raymond, Bull. M. C. Z., 1920, 64, p. 277. 

This family was erected for trilobites which resemble the Raphiophor- 
idae in the possession of narrow free cheeks without eyes, and a short, 
Ampyx-like pygidium, but which lack a glabellar spine. The typical 
genus is Endymionia. The family may be briefly characterized as 
follows: — 

Hyoparia with narrow dorsal free cheeks but no e^es, no glabellar 
spine, five to seven segments in the thorax, and a short ampycid 
pygidimn. 

Ordovician, Quebec, Newfoundland, Illinois, Scotland, Sweden. 

Endymionia Billings. Cephalon e^'enl^• convex with large glaliella 
divided into three parts by a pair of longitudinal furrows. Axial lobe 
of thorax about one third the total width. Type: — Endymionia 
vurki Billings. LoMer and Lower Middle Ordovician, Quebec and 
Newfoundland. 

Anisonotus Raymond. Cephalon irregularly convex, glabella small, 
with lateral furrows indicated by pits. Axial lobe of thorax narrow. 
Type: — Shumardia (jJacialis Billings. Lower and lower ^liddle 
Ordovician, Newfoundland, Scotland, Sweden. Other species which 
appear to belong to this genus are Anisonot'us hornei (Nicholson and 
Etheridge) from the Balclatchie (Llandeilo) of Scotland, and A. 
obtusus (]Moberg and Segerberg) from the Ceratopyge shales of Sweflen. 

Ampyxina Ulrich. Glabella hemispheric, reaching anterior margin 
of cephalon, one pair of glabellar furrows isolating basal lobes. Thorax 
with five segments. Type: — Endymionia bcUahda Savage. Upper 
Ordovician, Illinois. 



42 bulletin: museum of comparative zoology. 



Endymionia Billings. 

Endymion Billings, Pal. foss. Canada, 1862, 1, p, 93. 
Endymionia Billings, Ibid., 1865, 1, p. 281. 

This genus was described by Billings from a single nearly complete 
specimen found at Point Levis. 1 have since found a couple of quite 
well-preserved cephala and a pygidium at the t\'pe-locality and shown 
(Amer. journ. sci., 1914, ser. 4, 38, p. 530) that it comes from the thin- 
bedded limestone of the zone of Diplograptus dentatus, where it is 
associated with a considerable number of trilobites, brachiopods, and 
graptolites. 

The conspicuous features of the typical species are: — Absence of 
eyes, oval glabella with elongate lateral lobes, six or seven segments in 
thorax, Ampyx-like pygidium. This from Billings's specimen. Speci- 
mens collected by myself show that very narrow lateral free cheeks 
must have been present. 

Billings changed the name Endymion to Endymionia because he had 
learned that the former had been used for a genus of plants. This 
would not, of course, necessitate a change, but unfortunately Swainson 
used Endymion for a genus of Lepidoptera in 1832. 

On the same page with the above change of name, Billings stated 
that Endymionia meeki occurred abundantly in divisions N and P in 
Newfoundland. Schuchert and Twenhofel were fortunate enough to 
collect some good material, including entire specimens, at one of the 
localities referred to by Billings, and although they pro\e to belong to 
a distinct species, they add somewhat to the generic diagnosis, as they 
show that the thorax possessed seven segments. 



Endymionia meeki Billings. 

Endijmion meeki Billings, Pal. foss. Canada, 1862, 1, p. 94, fig. 84. 
Endymionia meeki Billings, Pal. foss. Canada, 1865, 1, p. 281. 

It is not necessary to redescribe this species, but it may be pointed 
out that since other species of the genus have proved to have seven 
thoracic segments, it is highly probable that seven rather than six was 
the correct number in Billings's imperfect specimen. Specimens col- 
lected by the writer show that narrow marginal free cheeks were 
doubtless present. A pygidium from Point Levis is somewhat better 
preserved than that on the original specimen and has five rings on the 
broad slightly convex axial lobe and three pairs, besides the anterior 



RAYMOND: ORDOVICIAN TRILOBITES. 43 

half rib, on the flat pleural lobes. There is a wide, flat, striated border 
sloping down all around at an angle of 45°, and at the junction with the 
flat upper surface is a narrow, raised, wire-like rim. 

Mrasurcmcnfs: — Billings gi\'es the following measurements of the 
type: — Length of specimen 5 lines (10 mm.), width at posterior margin 
of head, about 4 lines (8 mm.); length of head 2j lines (4.5 mm.); 
length of thorax If lines (3.5 mm.); length of pygidium about 1 line 
(2 mm.). A cranidium from Point Levis is 4.5 mm. long, and 9 mm. in 
width. The glabella is 3.75 mm. long, and 3 mm. wide. A pygidium 
is 2.5 mm. long, 6 mm. wide. 

Horizon and Locality: — This species has been found onl\' at Levis, 
opposite Quebec, P.Q., where Billings reported it from the "upper part 
of limestone No. 2, Quebec Group," and where 1 found it, as a very rare 
fossil, in the thin-bedded limestone at the base of the zone with 
Diplograptus clrntafus, in the Levis formation, Beekmantown in age. 
The particular locality is in the crest of the bluft' overlooking the road 
near the base of Begin Hill, about one half mile east of the station at 
Levis. 

ExDYMiONiA SCHUCHERTI Raymond. 

Plate 2, fig. 13. 

Endymionia schucherti Raymond, Bull. M. C. Z., 1920, 64, p. 277. 
Endymionia meeki Billings {partim), Pal. foss. Canada, 1865, 1, p. 281. 

Specimens of this species are larger than those of E. meeki, with 
smooth rather e^'enly convex cephalon, and flattened thorax and 
p\gidium. Lengths of cephalon, thorax, and pygidium in the pro- 
portion 2 : 2 : 1 . 

Cranidium a little more than twice as wide as long, smooth, gently 
and evenly convex. Glabella very large, depressed convex, with large 
lateral lobes strongly suggestive of Amphilichas. The outline of the 
whole glabella is roughly circular, the width l)eing a little greater than 
the length of the glabella and neck-ring. The confluent glabellar 
furrows follow exactly the same course as do those of an Amphilichas, 
separating large, oval, diagonally placed lateral lobes. The central 
lobe is narrowest a short distance in front of the neck-furrow, and 
widest at the front. In front of the glabella the cheek slopes down to a 
very narrow flattened or conca\e border which is absent from the 
sides, where narrow, free cheeks extending back to the genal angles 
and perhaps elongated into genal spines Avere probably present. No 
evidence of the presence of eyes remains, and it is prol)able that like 



44 bulletin: museum of comparative zoology. 

the Raphiophoridae these were blind trilobites with dorsal facial 
sutures. The neck-furrow is distinct all across the back of the 
cephalon, but narrow. The neck-segment is wider near the distal 
ends than near the axial lobe. 

The thorax has seven narrow segments, the axial lobe being gently 
convex and the pleural lobes flat. The axial lobe is rather wide, 
nearly one third the total width, and tapers Aery little from front to 
back. On the pleural lobe each segment shows a rather wide, deep, 
central furrow. 

The pygidium is short, Ampyx-like, with four rings on the wide 
axial lobe and three pairs of ribs on the pleural lobes, and is surrounded 
by a steeply sloping striated border. 

Mrasurcmcnfs: — Length of entire specimen : 10 mm. ; width at genal 
angles 9 mm.; length cephalon 4 mm.; thorax 4 mm.; pygidium 2 
mm.; width glabella 3.75 mm.; width axial lobe at front of thorax 2.5 
mm., at front of pygidium 2 mm.; width pygidium at front 6.5 mm. 
Largest cranidium length 9 mm., width 15 mm.; width glabella 8 
mm., length glabella 7.5 mm. 

This species is similar to E. nurki, and I should not have been able 
to separate the two had not specimens of both been before me. In 
E. schucherti the glabella is more nearly circular in outline, broader, 
and flatter than in E. iiirrki, and the median tubercle is fainter and 
farther forward, so faint in fact as to be invisible on most specimens. 
In E. )n('eki there is a strongly striated, abruptly sloping, border in 
front of the glabella, while in E. schucherti the corresponding portion 
is a smooth "roll" sloping down to a narrow concave border. 

Horizon and Locality: — Professors Schuchert and Twenhofel 
collected twelve specimens, three of them entire, from the limestones 
of division N (Normanskill) at Table Head, ^iM. Billings referred 
to this form as occurring abundantly in division N at Table Head 
and the west side of Pistolet Bay, also in division P, four miles north- 
east from Portland Creek, Nfld. The types are in the Yale University 
Museum. Named for Prof. Charles Schuchert. 

Anisonotus glacialis (Billings). 

Plate 2, fig. 17. 

Anisonotus glacialis Raymond, Bull. M. C. Z., 1920, 64, p. 279. 
Shumardia glacialis Billings, Pal. foss. Canada, 1865, 1, p. 238, fig. 270. 

Entire trilobite oval in outline, nearly as wide as long, the greatest 
width being at the back of the cephalon. The cephalon is strongly 



RAYMOND: ORDOVICIAN TRILOBITES. 45 

convex; the thorax and pygidium nearly flat except for the axial lobe, 
which is narrow and ele\ated. 

The cephalon is trinuclear, the swollen glabella rising above the 
mound-like fixed cheeks. The glabella extends two thirds of the length 
of the cephalon (measured on the curvature) and shows at the sides 
four pairs of pits. The last pair represent the neck-furrow, and the 
others the foiu'th, third, and second pairs of glaljellar furrows. The 
first and fourth pairs of pits are much less conspicuous than the others. 
The elevated glabella is bounded b^' a pair of narrow furrows which 
converge backward and outside these are two more which are parallel 
to the axis of the head. Between the parallel and the converging 
furrows are two slightly ele\ated triangular ridges, the apices pointed 
forward. 

Outside the parallel furrows on the cephalon there are two evenly 
rounded mounds, limited on the inside and back by straight grooves 
intersecting at right angles and at the front by a curving depression 
which joins the dorsal furrows opposite the anterior glal)ellar furrows. 
In this depression there is on each side a narrow but distinct eye-line 
which curves backward around the mound and continues to the 
border of the cheek, meeting it at the horizon of the neck-furrow. In 
front of this depression and of the glabella there is a rather abrupt 
bulging slope to the margin, which appears to be somewhat thickened, 
but probably without rim or brim. The exfoliation of the type gives 
the appearance of a ^'ery narrow brim on the front. 

At the genal angles the fixed cheeks are drawn back into short 
lapets which extend behind the neck-ring. These are semicircular in 
outline, and it is difficult to decide whether they are the actual genal 
angles, or whether they were en\eloped by spines belonging to the 
free cheeks. In front of the angles there is a slight sinuosity in the 
side of the cheek, and along this part the border which is present on 
the front of the cephalon is absent. This seems to indicate that free 
cheeks should be present, but very narrow ones as in most species of 
Ampyx. These cheeks would probably have borne the genal spines. 

The anterior portion of the cephalon is coveretl with very fine wavy 
lines, parallel to the anterior edge. 

The thorax has seven segments, and does not taper from front to 
back. The axial lobe is narrow, one fifth of the total width, and 
strongly elevated. The pleural lobes are flat, each pleuron bearing 
a linear groove whose course is at right angles to the axis. The first 
two segments do not extend quite so far at the sides as those behind, 
a common condition in trilobites with genal spines. 



46 bulletin: museum of comparative zoology. 

The p\ gidium is nearly semicircular, but has the somewhat triangu- 
lar appearance so often seen in pygidia of ampycids or trinucleids. 
The axial lobe is narrow, elevated, and extends almost to the posterior 
border. The pleural lobes are flat, and turn down but little to the \ery 
narrow thickened margin. Singularly enough, there is a ring on the 
axial lobe for each pair of ribs on the pleural lobes, so that rings and 
ribs are continuous. Nine distinct rings are present. The ribs are 
narrow and flat, with just a suggestion of an impressed line along the top. 

Mcasiircinrnts: — Length 14.5 mm., greatest width 13 mm., width 
at middle of thorax 10.5 mm.; length of cephalon 6.5 mm., width 
13 mm.; length glabella 4.5 mm., width of glabella at front 3.25 mm.; 
length of thorax 4 mm., width 10.5 mm.; width of axial lobe 2 mm.; 
length of pygidium 3.25 mm., width at front 9 mm.; width of axial 
lobe at front 1.5 mm. A flattened cephalon is 6 mm. long, 15 mm. 
wide; and the glabella is 4.5 mm. long. 

This species differs in many respects from Endymionia meeki. The 
glabella is shorter and considerably narrower, has four instead of two 
pairs of pits at the sides, and has much l^s prominent lobes beside it. 
E. meeki does not seem to have the mound-like cheeks, and eye-lines 
are absent. The axial lobe of the thorax is much narrower in A. 
(ihukdis than in E. meeki, and the furrows on the pleura are straight 
instead of sinuous. The pygidium of the present species has a nar- 
rower axial lobe and more rings and ribs than in the Beekmantown form. 

With the knowledge of this specimen it is possible to get a better 
idea of the characteristics of the Endymionidae. The form of the 
thorax and pygidium and the presence of narrow free cheeks approach 
very closely to the Raphiophoridae, being excluded from that family 
*as now defined only by the shortness of the glabella and the absence 
of a long spine therefrom. 

Horizon and Locality: — Billings's specimens came from the con- 
glomerates of Portland Creek and Pistolet Bay, Nfld. Hyatt found 
it on the east side at Port au Port, and Schuchert and Twenhofel 
obtained three fragments from the same locality. The horizon is 
their zone 6, Normanskill. Genoholotype (M. C. Z. 1,594). 

Anisonotus hornei (Nicholson and Etheridge). 

Ampyx mammillatus Armstrong and Young, Cat. est. Scot, foss., 1876, p. 15. 

Ampyx hornei Nicholson and Etheridge, Mon. Silur. foss. Girvan, 1879, 
p. 184, pi. 13, fig. 4, 8. Mem. Geol. surv. Silur. rocks Britain, 1899, 1, 
Scotland, p. 509, 672, 688. Reed, Palaeontogr. soc, 1903, p. 19, pi. 3, 
fig. 8-10. 



RAYMOND: ORDOVICIAN TRILOBITES. 47 

fAsaphus sp. Nicholson and Etheridge, Mon. Silur. foss. Girvan, 1879, p. 154, 
pi. 10, fig. 20. 

This species, of which the cranidium, part of thorax, and the p\ gi- 
dium have been well described and figured by Reed, is evidently an 
Anisonotus. The cranidium shows the long eye-lines and the glabella 
does not reach the front. The thorax is said by Reed to have six 
segments, and the pygidium agrees well with that of Anisonotus 
glacial is. A. hornci is from the Balclatchie Group (Llandeilo) of 
Scotland, and thus occurs at about the same horizon as A. glacialis. 

Anisonotus obtusus (Moberg and Segerberg). 

Ampyx obfvsus Moberg and Segerberg, Lunds univ. arsskr., 1906, n. f., 2, 
p. 100, pi. 7, fig. 8-10. 

This species agrees with Anisonotus rather than Ampyx in lacking a 
glabellar spine, and in the presence of a median pustule on the glabella. 
The glabellar furrows are merely faint pits, the eye-lines are very far 
forward, and the pygidium is nearly smooth, only faint traces of rings 
and ribs being visible. 

Horizon and Locality: — The specimens were derived from the 
Ceratopyge shales (basal Ordovician), at Berg in Oestergotland. 

Ampyxina Ulrich. 

Ampyxina Uh-ich, Bull. Geol. soc. Amer., 1922, 33, p. 206. 

This generic name was proposed by Ulrich in the published abstract 
of a paper read before the Palaeontological Society in December, 1921. 
His description is as follows: — "A new genus, Ampyxina, is proposed 
for small Ampyxidae with small and very short rostral spine, obovate 
glabella, a small pair of isolated posterior lateral glabellar lobes, and 
■four or five thoracic segments. The pygidium also differs from that of 
Ampyx and Lonchodomas in wanting the thick, beveled and striated 
posterior edge. In Ampyx the second and third pairs of lateral 
glabellar lobes often are rather well developed and partly separated 
from the middle lobe, but the posterior pair is seldom well defined and 
never isolated." 

As the genotype he designates, "provisionally," an unnamed trilo- 
bite described and figured by R. R. Rowley from the Maquoketa 
(Buffalo) shale west of Louisiana, Mo. For this he suggests the new 
name A mpyxina hasslcri. Unfortunately this appears to be the species 



48 bulletin: museum of comparative zoology. 

described b\' Sa\-age as Endymionia bellatula, and fails in some respects 
to fit the generic description, as it lacks a glabellar spine, has five seg- 
ments in the thorax, and a rather sharply deflected, rim-like border on 
the pygidium. 

At the time Dr. Ulrich's article appeared, 1 had in manuscript a new 
generic name for trilobites with the structure of Endymionia beUatuIa^ 
but am now obliged to substitute the one he has proposed. 

Ampyxina bellatula (Savage). 

Gen.? sp.? Rowley, Missouri bur. geol. and mines, 1909, ser. 2, 8, p. 60, pi. 15, 

fig. 12-14. 
Endymionia bellatula Savage, Trans. 111. acad. sci., 1917, 10, p. 273, pi. 1, fig. 3. 

Foerste, Bull. Denison univ., 1920, 19, p. 218. 
Ampyxina bassleri Ulrich, Bull. Geol. soc. Amer., 1922, 33, p. 206. 

This species was first noticed by Mr. R. R. Rowley, who gave three 
figures of specimens without assigning any name to them. He stated 
that it was not rare in the lower beds of the "Hudson River," four or 
five feet above the top of the Trenton. Savage, in his description, does 
not refer to Rowley's description or figures, but notes its occurrence 
near Dover Church, Pike Co., Mo. Foerste says " Prof. R. R. Rowley 
discovered long ago a locality on the Goodman place, ^ mile west of 
Calumet post-ofl[ice, where this little trilobite [Endymionia bellatula 
Savage] occurs in great abundance about 3 or 4 feet above the base of 
the Buffalo shales." Ulrich does not give any description, but applies 
the name Ampyxina bassleri to the specimens figured by Rowley. The 
latter, judging from the figures and descriptions, belong to Savage's 
species, so his specific name has priority. 

Endymionia bellatula is a small trilobite which combines some of the 
characteristics of Endymionia, Dionide, and Raphiophorus. The 
general aspect is that of Endymionia, from which it differs chiefly in 
having a longer glabella, which reaches the anterior margin, and only 
five instead of seven segments in the thorax. It is somewhat more like 
Raphiophorus with which it agrees in having five segments in the 
thorax and a l)ulbous glabella. As in that genus, the first thoracic 
segment is broader than the others, and has more curved furrows on 
the pleura. 

The glabella has a pair of diagonal furrows which isolate small basal 
lobes, and the cheeks do not appear to have either genal caeca or the 
characteristic ornamentation of Dionide. 

This condition is similar to that in Endymionia, except that the 



RAYMOND: ORDOVICIAN TRILOBITES. 49 

lobes are very much smaller, and since the dorsal furrows are straight 
and parallel in the posterior parts of their courses, the resultant ap- 
pearance is more nearly like that of Tretaspis than Endymionia. 

The appearance of crushed specimens is so much like that of flat:- 
tened specimens of Raphiophorus that they would naturally be 
referred to that genus were it not for the absence of a glabellar spine. 

Ampyxina and Dionide are alike in having a bulbous glabella and 
in the differentiation of the first of the thoracic segments from the 
others. The glabellar furrows are, however, differently placed, there 
are five instead of six thoracic segments. 

Professor Savage was good enough to send me a number of specimens 
of this species, and 1 am able to modify his excellent description only 
in regard to the glabellar furrows and the first segment of the thorax. 
Nearly all the cranidia are so flattened that the glabellar structure is 
obscure, but a few, particularly one preserving the test and exposed 
from the lower side, show that the dorsal furrows are straight and 
parallel nearly to the front of the cranidium. On either side of the 
glabella is a groove which originates in the dorsal furrow and runs 
back into the neck-furrow, thus isolating a pair of long, narrow basal 
lobes, and producing a nearly circular outline for the central part of 
the glabella. One uncrushed cranidium shows that the glabella is 
elevated high above the fixed cheeks and reaches to the anterior margin. 
If free cheeks were present on the dorsal surface, they must have been 
\ery narrow. 

The furrows on the last four segments of the thorax are nearly 
straight, but each crosses its pleuron diagonally, being near the 
anterior edge mesally and the posterior one at the outer end. The 
first segment is wider than the others, and the groove, originating at 
the posterior inner angle, describes a graceful curve forward, nearly 
reaching the anterior margin at the middle, and the posterior angle 
at the outer end of the pleuron. Similarly marked first segments are 
present on some species of Dionide and Raphiophorus. 

Horizon and Locality: — Savage reports the species from the Thebes 
sandstone (Richmond) near Thebes, 111., also along Madison Creek, 
Calhoun Co., 111., and near Dover Church, Pike Co., Mo. Foerste 
records its discovery by Rowley near Calumet post office. Mo., in the 
Buffalo shales (Maquoketa). Rowley gave no locality. 



50 bulletin: museum of comparative zoology. 

OPISTHOPARIA Beecher. 

Olenidae Burmeister. 
Triarthrus Green. 

Triarthrus seems to be very largely a North American genus, and 
reaches its greatest development in our Middle Ordovician. It is, 
however, an olenoid trilobite, and is to be looked upon as a survivor 
of the Upper Cambrian fauna. Such being the case, it is rather sur- 
prising that members of the genus are relatively rare in early Ordovi- 
cian faunas in America. In northern Europe, however, the majority 
of the species occur low in the Ordovician, but do not seem to be 
common. 

List of the Species with References and Horizons. 

American species. 

Beekmantown. 

Triarthrus belli ISIatthew, Bull. Nat. hist. soc. New Brunswick, 
1902, no. 20, p. 412, pi. 18, fig. 8. 

Normanskill. 

Triarthrus fischeri Billings, Pal. foss. Canada, 1865, 1, p. 291, fig. 280. 

Upper Middle Ordovician. 

Triarthrus becki Green, Mon. tril. N. Amer., 1832, p. 87, pi. 1, fig. 6. 
Trenton and "Utica" shales. 

Triarthrus becki macasteyensis Twenhofel, Bull. Victoria mem. mus., 
1914, 3, p. 35. Macastey shale ("Utica"). 

Triarthrus billingsi Barrande, Syst. Silur. Boheme. Suppl., 1872, 
p. 427, pi. 32, fig. 4, 5. Utica. 

Triarthrus canadetwis Smith, Canad. journ., 1861, new ser., 6., p. 275, 
fig. Gloucester ("Utica"). 

Triarthrus glaber Billings, Canad. nat. geol., 1859, 4, p. 382. " Utica." 

Triarthrus spinosus Billings, Geol. surv. Canada. Kept, progr., 
1853-1856, 1857, p. 340. Gloucester ("Utica"). 

European species. 

Ceratopyge zone (Basal Beekmantown). 

Triarthrus angeUni Linnarsson, Kongl. svenska vet.-akad. Handl., 
1869, 8, p. 70, pi. 2, fig. 28. Sweden and Norway. 

Lower Dicellograptus zone (Normanskill). 

Triarthrus becki //m?»//w Hadding, Lunds univ. arsskr., 1913, n.f., 9, 
p. 69, pi. 6, fig. 18, 19. Sweden. 



RAYMOND: ORDOVICIAN TRILOBITES. 51 

Triurfhriis joiitlandicus Linnarsson, Geo), foren. Forhandl., 1875, 
2, p. 493, pi. 22, fig. 2, 2a. Sweden. 

Triarthrufi hrcki Green (var.) Reed, Palaeontogr. soc, 1903, 57, p. 
28, pi. 4, fig. 10. Balclatehie group (Llandeilo), Scotland. 

Tpper Middle Ordovician. 

Triarthrus brcki Green. Linnarsson, Kongl. Svenska vet.-akad. 
Handl., 1869, 8, p. 70, pi. 1, fig. 27. Chasmops limestone (Trenton). 
Sweden. 

I pper Ordovician. 

Triarthrus pygmaeus Tornquist, Sveriges geol. iindersokning, 1884, 
ser. C, no. 66, p. 38, pi. 1, fig. 40. Trinucleus shales (Richmond), 
Sweden. 

In the above list of the eight American species and varieties, six are 
Upper Middle Ordovician (Trenton and Utica), whereas in Europe 
three of the six species are Lower Middle Ordovician, one Lower Ordo- 
vician, one Upper Middle, and one Upper Ordovician. 

Several of the species are imperfectly known and seem to lack strik- 
ing distinguishing characteristics. Triarthrus canadensis and T. 
spinosus are of course somewhat sharply separated from the other 
species by their spines. 

Trl\rthrus fischeri Billings. 
Triarthrus fischeri Billings, Pal. foss. Canada, 1865, 1, p. 291, fig. 280. 

Triarthrus fisrhrri was poorly described and figured by Billings, and 
has not been redescribed. Of the species from the Utica, T. glaber is 
most like T. fischeri, the two agreeing in lacking spines and in having 
no tubercles along the axial lobe. Although not shomi in Billings's 
figure, T. fischeri has a narrow, upturned rim in front of the glabella. 
This rim is separated from the glabella by a narrow furrow, which, in 
this species extends around the front of the cranidium, whereas in T. 
(jlaher and T. hecki the circumglabellar furrow is not confluent with the 
furrow inside the rim on the cheeks. The glabella of T. fischeri con- 
tracts slightly toward the front; in T. hecki it expands. As Billings 
has remarked, the specimens from the Trenton and Utica are much 
larger than those from the Xormanskill. Comparison should rather 
be made with the species found at the same horizon in Europe. 

Of the latter, T. hecki humilis Hadding differs in having the eyes 
farther forward, the glabellar furrows more arcuate, and in lacking the 
anterior pair of furrows. The species described by Reed from the 
Girvan district of Scotland as Triarthrus hecki is entirely unlike both 



» 



52 bulletin: museum of comparative zoology. 

T. fischcri and T. hrcki in ha\"inf>; almost straight glabellar furrows, and 
with the neck-furrow of the glabella confluent with that of the cheeks. 
As the Scottish species is certainly not identical with Triarthrus brclci 
1 propose that it shall be known as Triarthrus recdi. 

Triarthrvs jnntlandinis has been best described and figured by 
Wiman (Bull. Geol. inst. -Upsala, 1902, 6, p. 79, pi. 5, fig. 5-8), who 
rightly objected to Holm's uniting it with T. hrcki. Specimens from 
the type-locality, figured h\ Wiman, are distinctly pointed in front, 
have very narrow glabellar furrows, faint dorsal furrows, and are in 
general quite different from all other species of the genus. 

Triarihrus fischcri is therefore quite distinct from other species found 
at the same horizon, but quite like the later Triarthrus glahcr. 

Horizon and Locality: — Billings's specimens of this species were 
found in division N at Table Head and Pistolet Ba>t', and in division 
P at Portland Creek, Nfld. The specimens in the M. C. Z. were 
obtained by Professor Hyatt on the eastern shore of the Bay at Port au 
Port, Nfld.' 

Professors Schuchert and Twenhofel collected cranidia from zone N2 
and the Isolated limestone at Table Head, and cranidia and fragments 
of the thorax from Port au Port. 

Triarthrus reedi, sp. nov. 
Triarthrus becki var. Reed, Palaeontogr. soc, 1903, 57, p. 28, pi. 4, fig. 10. 

As mentioned (page 51) the Scottish form which has been identified 
as Triarthrus bccki differs from that species in having almost straight 
glabellar furrows, and in ha\ing the neck-furrow continuous across the 
cheeks and posterior end of glabella. It appears to occur at a lower 
horizon (Llandeilo) than does the true T. bccki. 

Triarthrus caectgenus Raymond. 
Plate 2, fig. 16. 
Triarthrus caecigenus Raymond, Bull. M. C. Z., 1920, 64, p. 280. 

Entire test o\'al, of the usual shape in this genus, without spines or 
pustules except for a small one on the neck-ring. 

Cephalon somewhat irregular in outline, the glabella projecting in 
front of the cheeks. Glabella long and wide, with a very narrow 
circumglabellar furrow and upturned border. There are two pairs of 
glabellar furrows which run inward and somewhat backward and are 



c 

I 






RAYMOND: ORDOVICIAN TRILOBITES. 53 

deeply impressed, particularly at tlieir inner ends. Fixed cheeks 
narrow, with a somewhat wide convex marginal border which extends 
around the sides and connects with the neck-ring. A truncation of 
this border at the sides suggests the possible former presence of \ery 
narrow free cheeks, but there are no traces of palpebral lobes. 

Thorax with (apparently) eleven segments. Axial lobe wide and 
the rings smooth. 

Pygidium strongly segmented, with about six pairs of ribs on the 
pleural lobes and seven rings on the axial lobe. 

Mrasuronrjits: — Length 11.5 mm. Length cephalon 3.5 mm.; 
thorax 5.5 mm.; pygidium 3 mm. Width at genal angles 6 mm.; 
Avidth glabella 3 mm.; width axial lobe at front 2.75 mm.; width 
pygidium 4 mm. 

This species can be distinguished from all others by the absence 
of eyes. The most closel\' allied species is Triarfhnis humilis Hadding 
which has the eyes far forward and the free cheeks very narrow. 

Horizon and Locality: — A rather common species in the Athens 
shale in the Catawba Valley, north of Salem, Va., where the type was 
collected by Prof. S. L. Powell, and also at Lasker's Gate, three miles 
northeast of Blacksburg, Va., where it was collected by Dr. R. ]VI. 
Field and the writer. A few specimens were also found at Salt\'ille,% 
Va., near the base of the Athens. Holotype (M. C. Z. 1,593). 

Ceratopygidae Raymond. 

Crepicephalus ceratopygoides, sp. nov. 

Plate 2, fig. 15. 

Among the fossils collected by Mr. Shepard in British Columl)ia is a 
rather poorly preserved pygidium which closely simulates that of 
Ceratopyge, but is more probably referable to Crepicephalus, a genus 
hitherto supposed to be confined to the Cambrian. 

Cephalon and thorax unknown. 

Pygidium approximately semicircular, with a pair of lateral spines 
projecting from the pleural lobes just back of the middle. Axial lobe 
narrow, with five conspicuous and two faint rings. Pleural lobes 
poorly preserved, but apparently smooth except for a pair of furrows 
just behind the anterior margin. The lateral spines are not mere 
extensions of the margin, but are prolongations of the convex portion 
of each pleural lobe. 

This species belongs to the Crrpiccphaluit tvxanus group, but is not 



54 bulletin: museum of comparative zoology. 

very closely allied to any known species. It has a wider pygidiuni, the 
axial lobe is narrower, and has more rings, than any species pre\iously 
described. In the features just enumerated it is much more like 
Ceratopyge forficida Sars than like any Crepicephalus. It would be 
referred to Ceratopyge were it not for the fact that in that genus the 
spines are outlined as a distinct segment all across the pleural lobes. 

One reason for the reference of this pygidium to Crepicephalus is the 
presence in the collection from the same locality of a small cranidium 
(Plate 2, fig. 14) which appears to belong to that genus, although 
whether it represents the same species as the pygidium is problematical. 

The specimen (M. C. Z. 1,675) is very small (4 mm. long) and doubt- 
less represents an immature specimen. The glabella is highly con\'ex, 
unfurrowed, and its really semielliptical shape is obscured by a pair of 
pits in the circumglabellar furrow near its anterior end. At the 
anterior margin of the cephalon there is a raised border, and in the 
furrow behind it, obscure traces of three pits, suggesting those of some 
species of Crepicephalus. These pits are so faint that it was thought 
best not to attempt their illustration. 

Measurements: — ^ The pygidium, which is the holotype (M. C. Z. 
1,674), is 14 mm. long, and 27 mm. wide. The axial lobe is 6 mm. wide 
at the anterior end, and 12 mm. long. A pygidium- of C. texanvs fig- 
ured by Walcott is 15 mm. long, 25 mm. broad; and the axial lobe is 
10 mm. wide. 

Horizon and Locality: — The holotype was collected by Dr. Francis 
P. Shepard from the Lower Ordo\'ician east of Harrogate, B. C, 
associated with a fauna characteristic of the Pogonip formation. 

Solenopleuridae Angelin. 

IscHYROTOMA, gen. nov. 

This generic name is suggested for small Opisthoparia with short 
highly convex cephalon, small eyes near the glabella, long, convex, 
oxaX glabella with no or inconspicuous lateral furrows, and steeply 
sloping cheeks which produce a strongly notched appeai'ance at the 
front of the head. Type: — I schyrotoma tivenhofeli, sp. now 

IsCHYROTOMA TWENHOFELI, sp. nOV. 

Plate 3, fig. 1, 2. 

Cephalon narrow, trilobed, highly convex. Glabella long, semi- 
cylindrical, the anterior end rounded and overhanging the frontal 



RAYMOND: ORDOVICIAN TRILOBITES. 55 

border. Very faint traces of two pairs of glal)ellar furrows are shown 
by slight indentations in the sides back of the eyes. The dorsal fur- 
rows are deep and narrow, the neck-furrow deep and wide, so that the 
glabella is completely isolated. 

The fixed cheeks are narrow, the free cheeks convex, turned down- 
ward at the sides. Both eyes are broken off, but the position of one is 
shown opposite the middle of the glabella and close to the dorsal fur- 
row. The genal angles appear to have l)een rounded, and the cheeks 
have a narrow convex outer border separated from the general surface 
bv a narrow furrow. In front of the exe the facial suture runs nearly 
parallel to the dorsal furrow and close to it, turning inward to cut the 
margin near the middle of the front. Due to the broken surface the 
greater part of the course back of the eye cannot be seen, but it cuts 
the border at the genal angle. 

The surface of the glabella bears numerous small pustules, and simi- 
lar ones are scattered more sparsely over the cheeks. 

Isolated glabellae might well be confused with those of Petigurus, 
Goniurus, and other trilobites, so that positive identifications cannot 
be made without fairly good material. 

Measurements: — Length of cephalon 6 mm., width about 10 mm. 

Horizon and Locality: — The holotype was obtained from a pebble in 
the Cow Head conglomerate at Lower Head, Nfld., and is in the Yale 
L'niversity Museum. A second specimen was collected by the writer 
from a boulder in the conglomerate on lot 22, Concession VI, two miles 
north of Mystic, Quebec. 

Remopleuridae Corda. 

This is a small famil>, of relatively rare and specialized trilobites, 
characterized especially by the long eyes and flat glabella. It has 
been frequently stated that Remopleurides was a direct descendant of 
Paradoxides, and the genus placed in the same family with that form. 
A study of the older Ordovician species has suggested that it is more 
probable that the proximate ancestor is to be found in the Dikolo- 
cephalidae. These families approach each other most closely in 
Apatokephalus on the one hand and Rohcrgia micropthalma on the 
other, and the tendency within the Remopleuridae seems to be toward 
a reduction in the size of the pygidium, suggesting that they had their 
origin in an isopygous group. 

The following are the recognizable genera of this family : — 
Remopleurides Portlock. Glabellar furrows faint or absent. Ante- 



56 bulletin: museum of comparative zoology. 

rior tongue of glabella usually short, without marginal border. Axial 
lobe of thorax wide, fulcral nodes strongly developed. Pygidium very 
short and broad with two pairs of short spines. Hypostoma bifur- 
cated, with very long forks. Type: — Rcmoplcurides colbii Portloek. 
Middle Ordovician, northern Europe and America. 

Robergia Wiman. Glabellar furrows narrow but deeply impressed. 
Anterior tongue of glabella elongate and with a marginal border. 
Thorax narrow, axial lobe wide, pleural lobes very narrow and flat, 
without fulcral prominences. Pygidium flattened, with medium to 
long axial lobe, and three or two pairs of flat spines on the posterior 
margin. Hypostoma as in Remopleurides. Type: — R. micropthalma 
Linnarsson. Lower Middle Ordovician, northern P^urope and North 
America. 

Caphyra Barrande. Glal)ellar furrows distinct, anterior tongue 
of glabella short, a border present. Axial lobe of thorax wide, pleural 
lobes wider than in Robergia, fulcral nodes present, but not prominent. 
Pygidium long, narrow, and flat. Axial lobe short. Posterior margin 
with two pairs of spines. Hypostoma large, nearly square, not 
bifurcated. Type: — Caphyra /W/o/is Barrande. Upper Ordovician, 
Bohemia and Scotland. 

Teratorhynchus Reed. Glabella with two pairs of furrows. Ante- 
rior tongue very long, with spines at the front. Thorax with wide 
axial lobe, narrow pleural lobes with weak development of fulcra. 
Pygidium short with two pairs of spines. Type: — Teratorhynchus 
hicornis Reed. Balclatchie Group, Llandeilo, Girvan district, Scotland. 



Remopleurides panderi Billings. 
Remopleurides panderi Billings, Pal. foss. Canada, 1865, 1, p. 293, fig. 283. 

This species appears to be rare, and is easily recognized by its small 
size and the deep pits which represent the posterior pair of glabellar 
furrows. These are situated far back on the glabella, and join the 
neck-furrow. Faint traces of another pair can be seen on some 
specimens. 

Measurements: — Length of cranidium 1.5 mm.; width at palpebral 
lobes L75 mm. 

Horizon and Localify: — Billings described this species from division 
N, Table Head, Nfld. Professors Schuchert and Twenhofel collected a 
few specimens from zone M2 and from the Isolated limestone at Table 
Head, both of Normanskill age. 



RAYMOND: ORDOVICIAN TRILOBITES. 57 

Remopleurides canadensis Billings. 

Remophurides catiadensis Billings, Pal. foss. Canada, 1865, 1, p. 182, fig. 164. 
Raymond, Ann. Carnegie mus., 1905, 3, p. 334, 366, fig. 9, pi. 10, fig. 8-10. 
Bassler, Bull. 2a, Geol. surv. Virginia, 1909, p. Ill, fig. 10. Raymond, 
Ann. Carnegie mus., 1910, 7, p. 60. 7th rept. Vermont state geol., 1910, 
p. 217, pi. 32, fig. 8-10. Grabau and Shimer, N. A. index fossils, 1910, 
2, p. 270, fig. 1564. 

Two glabellae of this species, each about 5 mm. long, were collected 
from the Holston in the Catawba Valley, north of Salem, Va. The 
surface is gently convex, faintly granulose, and with very slight traces 
of glabellar furrows. 

Horizon and Locality: — The original locality of this species was in 
the Upper Chazy (Aylmer) in the front concession of the township of 
Clarence, Ontario, Canada. It is fairly common in the Middle Chazy 
at ^"alcour Island, and Chazy, N.Y., and rare in the Holston of the 
Catawba Valley, Va. Dr. Bassler has reported it from the Liberty 
Hall at Lexington, Va. 

Remopleurides rugicostatus, sp. nov. 
Plate 3, fig. 3. 

A single incomplete enrolled specimen appears to represent a species 
closely allied to R. canadensis. 

The glabella is very smooth, without granulations, and the furrows 
are just barely perceptible. Neck-furrow and neck-ring narrow. 

The thorax, which appears to be complete, has eight segments of the 
same kind as those of R. canadensis, but the most obvious difference 
between the two species is that in the form now described, the anterior 
part of each pleuron is longitudinally grooved. 

The pygidium is too poorly preserved to be described in detail, but 
is apparentl\' like that of R. canade7isis. 

Horizon and Locality: — Theholotype (M. C. Z. 1,611) was collected 
by the writer from the Ridley limestone near Stone River, two miles 
northwest of Murfreesboro, Tenn. 

Remopleurides striatulus Walcott. • 

Plate 3, fig. 4, 5. 

Remopleurides striatulus Walcott, Cine, quart, journ. sci., 1875, 2, p. 345, 
fig. 27A, a, b. Miller, N. Amer. geol. and pal., 1889, p. 566, fig. 1054 , 
Foerste, Bull. Denison univ., 1920, 19, p. 222, pi. 22, fig. 18A, B, C. 



58 bulletin: museum of comparative zoology. 

Walcott's original description of this species is accompanied by a 
rather sketchy figure of an entire specimen. 1 am therefore pubHshing 
a new figure, drawn from the type. Dr. Walcott obtained a number 
of cranidia and hypostomata from the original locality, but only two 
specimens which shoM' anything of the pygidium, and both of these are 
somewhat damaged. The pygidium of the type is less well preser\'ed 
than that of the other specimen. The latter shows that this shield is 
small, roughly rectangular in outline, longer than wide. The surface 
is evenly con\ex, sloping to the sides and posterior margin and is 
marked by neither axial lobe nor pleural ribs. The surface is crossed 
by cracks which at the anterior end are convex backward while on the 
posterior three fourths, they are concave backward. The posterior 
margin is not preser\ed, but appears to have had one or two pairs of 
blunt flat spines. This type of pygidium is very unlike that of 
Remoplcuridcs canadensis, which is shorter than wide, and ends in 
distinct spines. 

The glabella is moderatel^^ convex and its furrows are so obscure 
that they can only be made out by careful study, and on many speci- 
mens cannot be seen at all. The surface of the glabella is in some 
specimens granulated all over but in others it is very nearly smooth 
along the middle, and covered with sharp granules in the areas en- 
circled by the eyes. These details are of course very difficult to show 
in illustration and in figures it is necessary either to leave off the 
glabellar furrows and ornamentation entirely, or exaggerate them. 

Horizon and Locality: — The original examples collected by Dr. 
Walcott were from the upper third of the Trenton at Trenton Falls, 
N. Y. It has since been collected in the middle and upper Trenton 
at various places in Ontario. The cotypes are M. C. Z. 1,610-1,618. 



ROBERGIA 8CHL0THEIMI (BiUings). 

Remopleurides ? schlotheimi Billings, Pal. foss. Canada, 1865, 1, p. 294, fig. 284, 

a, b. 

Apatokephalus schlotheimi Brogger, Nyt. mag. natur., 1897, 36, p. 175, fig. 8a, 

b, p. 184. 

Wiman proposed Robergia (Geol. foren. Forhandl., 1875, 2, p. 494, 
pi. 22, fig. 3) for trilobites of the type of Remopleurides micro phthalmus 
Linnarsson, which have the general aspect of a Remopleurides or 
Caphyra, but have a larger, broader pygidium, the glabella prolonged 
some distance in front of the eves, and encircled by a narrow flat 



RAYMOND: ORDOVICIAN TRILOBITES. 59 

border. Apatokephalus Brogger has a very similar head and pygidium , 
but the facial sutures turn abruptly outward in front of the eyes. 

This species seems to be rather rare in Newfoundland, and 1 have 
seen specimens from onl\- two localities, Port au Port, and St. John 
Island. Onl\' cranidia and p\gidia ha\'e been found, and these are all 
poorl\' preserved. The best specimens show that the glabella expands 
slightly in front of the eyes, and that there is a narrow flattened border 
around its front. The anterior glabellar furrows are very short, re- 
duced to mere pits in some specimens; the median ones are long. 

The pygidium, of which 1 have seen only a single example, is nearly 
rectangular, longer than wide, with the outer points reaching farther 
back than the inner ones, thus forming a reentrant angle in the posterior 
outline. The axial lobe is ele^'ated, narrow, tapering to an acute 
point a little back of the middle. It appears to have only two cross- 
furrows on it, these near the anterior end. The pleural lobes are 
practically flat, and at the posterior margin there are four bhmt flat 
points or spines, the outer pair extending farther back and being 
broader than the others. 

The cranidium of this species is exceedingl\' like that of R. microp- 
thahua (c/. especially Hadding, Lunds univ. arssk., 1913, n. f., 9, 
p. 78, pi. 8, fig. 15-18), indeed, 1 see no important dift'erences, but both 
species are, of course, imperfectly known. Billings thus describes the 
pygidia : — " The pygidium found in association with the glabella 
somewhat resembles that of Dikelocephalus [Hungaia] magnificvs. It 
is ovate with an acutely conical axis, the side lobes with five or six well- 
defined ribs each. The axis is about half the whole length, and the 
ribs of the side lobes incline backward like those of a Remopleurides. 
The specimens are too obscurely preser\ed to be figured." From this 
it seems that the ribs on the pygidium were much more prominent 
than in the one I ha\'e before me, and unless a di\'ided rib was counted 
by Billings as a pair, there were twice as many ribs as on the pygidium 
■in the M. C. Z. specimen. 

In any case, the outline of the posterior end of the pygidium is very 
different in the American and Swedish species. In R. micropthalma 
it is convex, and there are three pairs of spines, the outer ones being- 
shortest, whereas in R. scklothnmi the outline is concave and the..outer 
spines are longest. 

Measure menis: — A cranidium from Newfoundland is 7 mm. long, 
and 7 mm. wide at the palpebral lobes. The glabella extends 2.5 mm. 
in front of the palpebral lobes. A cranidium from the Catawba 
Valley, Va., is 2.5 mm. long, 2.25 mm. wide; and the glabella projects 



60 bulletin: museum of comparative zoology. 

.75 Jiim. ahead of the palpebral lolies. A pygidium from Xew- 
foundland is 7 mm. long, and 5 mm. wide. 

The specimen from Newfoundland differs from the next to be de- 
scribed in having the pygidium of different outline and with shorter 
and narrower axial lobe. 

Horizon atul Locality: — This species has so far been found only in 
division N at Port au Port and on the southern side of St. John 
Island, Xfld., and in the Athens in the Catawba Valley, thirteen miles 
north of Salem, Va. 

RoBERGiA MAJOR Raymond. 

Plate 3, fig. 6-10. 

Robergia major Raymond, Bull. M. C. Z., 1920, 64, p. 281. 

Robergia sp. Raymond, Mem. Conn. acad. sci., 1920, 7, p. 145, fig. 40. 

Cephalon large, rounded in front, wider than long, with long narrow 
spines at the genal angles. 

Glabella elongate, a little expanded in front of the long eyes, with 
three pairs of furrows on the wide portion between the eyes. In front 
of the glabella there is an extremely narrow flattened border. Free 
cheek narrow, extended backward into a narrow spine of about its own 
length. 

Hypostoma bifurcated, with two very long prongs, as in Remo- 
pleurides. 

Thorax known from two incomplete specimens, the larger with nine 
segments. Judging from these specimens the thorax is long, narrow, 
slightly tapering. The axial lobe is wide, convex; the side lobes flat 
and narrow, the individual segments ending in short spines. 

Pygidium nearly square, as long as wide, sides straight and slightly 
convergent. Axial lobe elevated, extending three fourths of the length, 
wide at the front, tapering regularly backward. There are six well- 
marked rings. Pleural lobes practically flat, apparently crossed by 
obscure ribs, but all specimens are exfoliated, showing a wide striated 
doublure. The posterior margin shows two pairs of short flat spines, 
the inner ones being wider than the outer, and extending practically as 
far back. 

Mcasurcmrnts: — A large cranidium is 15.5 mm. long, and 15 mm. 
wide at the palpebral lobes. Nine segments of a thorax are 7.5 mm. 
long, 4 nun. wide at the anterior end, and 3.5 mm. wide at the posterior. 
The axial lobe is 2.5 mm. wide at the front. A pygidium is 10 mm. 
long, 10 mm. wide at the anterior end, and 9 mm. wide at the posterior 



I 



RAYMOND: ORDOVICIAN TRILOBITES. Gl 

end. The axial lobe is 5 mm. wide at the anterior end, and 7.5 mm. 
long. 

This species is exceedingly abundant in the Athens at Saltville, 
Va., and though no complete specimens ha\"e so tar been found, it is 
known from all the parts, including the hypostoma, which cannot be 
said of any other species of the genus. It differs but little from 
Robergia schlothrimi, such differences as there are being in the pygidium, 
which has a longer and wider axial lobe, is more nearly square, and has 
a straighter posterior margin. It differs from the Swedish R. microp- 
thalma chiefl\' in the pygidium which is much more nearly square and 
has two instead of three pairs of spines. 

Horizon and Locality: — A very abundant species in the lower part 
of the Athens at Saltville, Va., but not yet found elsewhere. Cotypes 
(M. C. Z. 1,()01-1,606). 

Robergia marginalis, sp. nov. 
Plate 3, fig. 11. 

A small trilobite, known from cranidia and pygidia only. 

C'ranidium similar to that of the type of the genus, l)ut with a 
relatively wide brim in front of the glal)ella; this brim is depres.sed 
convex, without raised border, concentrically striated, and has a row 
of small circular pits in the depression adjacent to the glabella. Gla- 
bella moderately convex, narrow, granulose. The glabellar furrows 
are unusually lightly impressed for a Robergia. The posterior ones 
are short and rather deep, directed obliquely outward. The other two 
pairs are only lightly impressed, and are parallel to and of the same 
length as the posterior ones. The median furrows do not run out on 
the palpebral lobes as is usual in the genus. 

The palpebral lobes are very large, semicircular in outline, and extend 
so far back that the posterior edges o\erhang the nuchal segment. 
The latter is wide, set off hy a narrow but distinct fiu'row. 

The facial sutures, in front of the eyes, turn slightly outward and 
then converge, so that the brim is obtusely pointed. 

The associated pygidium, which may, of course, not belong with 
these cranidia, has more divergent spines than usually seen in this 
genus. The axial lobe is narrow, pointed behind, extending to the 
reentrant between two spines at the posterior margin. There are 
three well-defined rings at the anterior end, and suggestions of two 
more. The pleural lobes are nearly flat, three pairs of ribs rising above 
the general surface for short distances. These ribs end in short flat 



62 bulletin: museum of comparative zoology. 

marginal spines, and between the last two there are two small sub- 
sidiary spines, one on either side of the median line. The latter spines 
appear to be present on one and absent from the other of the two 
pygidia found. 

Mfasmrmrnfs: — One of the cranidia is 5.5 mm. long, 4.5 mm. wide 
at the palpebral lobes, and 4.0 mm. wide where the facial sutures are 
most divergent in front of the eyes. The palpebral lobes are 2.25 mm. 
long on another cranidium which is 5.0 mm. long. 

A pygidium is 4.25 mm. long, including spines, and 4.00 mm. wide. 
The axial lobe is 3.00 long and 1.75 mm. wide at the front. 

This species differs from all other known Robergias in the breadth 
of the brim at the anterior end of the glabella and the shallowness of 
the anterior pairs of glabellar furrows. Another remarkable feature is 
the row of circular pits on the brim. This of course suggests Tramoria 
punctafa Reed (Quart, journ. Geol. soc. London, 1899, 55, p. 758, 
pi. 49, fig. 14-16) from County Waterford, Ireland. The row of pits 
in that species is, however, farther forward than in the present one. 
The latter, however, departs so widely from the typical Robergia that 
1 should have placed it in Tramoria, had it not been for the total 
absence of the first two pairs of glabellar furrows in the type of that 
genus. Robergia niargiuulis appears to stand about half-way between 
Tramoria and typical Robergia. That Tramoria is a synonym of 
Apatokephalus, as suggested by Reed in a more recent paper, seems 
very improbable. 

Horizon and Localify: — Three cranidia and two pygidia of this 
species were found in the lower part of the Lenoir, one mile east of 
Bluft' City, Tenn. Cranidium (M. C. Z. 1,721) is designated as the 
holotype, and pygidium (M. C. Z. 1,722) as paratype. 

Robergia breviceps, sp. nov. 

A small form, known from the cranidium only. The glabella differs 
from that of most species of the genus in that it enlarges slightly toward 
the front and the anterior end is somewhat abruptly truncated, turning 
down into a deep narrow furrow which separates the glabella from the 
narrow flat anterior border. There are only two pairs of furrows, the 
posterior ones being curved depressions opposite the middle of the 
palpebral lobes, and the anterior pair deeper oblique sulci which reach 
the dorsal furrows at the anterior ends of the eyes. The palpebral 
lobes are very large, one half as long as the cranidium. The surface 
of the glabella and neck-ring is minuteh- granulose. 



RAYMOND: ORDOVICIAN TRILOBITES. 63 

Measurements: — The holotype is 3 mm. long, and 3 mm. wide at the 
palpebrallobes. One palpebral lobe is 1.5 mm. long. A larger 
cranidivnn, which lacks the anterior flattened border, is 5 mm. long. 

This species differs from R. schJoiheimi in ha\ing two instead of three 
pairs of glabellar furrows and in the shape of the anterior end of the 
glabella. R. micropthalma Linnarsson, R. scaiiica Hadding, and R. 
barraudei Etheridge and Nicholson, also have three pairs of furrows. 

Horizon and Loealify: — Three cranidia of this species were found in 
the conglomerate on lot 22, concession \l, two miles north of Mystic, 
Que., in a boulder where they were associated with Arthrorhachis 
(jaJha (Billings) and other trilobites not yet identified. The holotype 
is M. C. Z. 1,727. 

Cyclopygidae, nom. nov. 
{Aeglinidae Pictet). 

Opisthoparia with large glabella, reduced fixed cheeks, eyes occupy- 
ing nearly the whole of the free cheeks. Thorax with few segments, 
generally about six; pygidium short, with few traces of segmentation. 

In his preliminary notice of the trilobites of Bohemia (1847, p. 34), 
Barrande described as Egle redivha a very curious animal whose free 
cheeks were occupied almost exclusively by the numerous lenses of very 
large eyes. The name Egle was considered b\' ( 'orda to be an incor- 
rect rendering of Aegle, already in use for a genus of plants. He 
therefore replaced it by Cyclopyge. Barrande in 1852 admitted that 
Egle was preoccupied, but proposed Aeglina in preference to Cyclo- 
pyge, and that name is in current use. It is, of course, not necessary 
to give up a name for a genus of animals because it is also in use for a 
group of plants, but unfortunately, Egle seems to have suggested itself 
to several taxonomists, for Aegle was used at least three times before 
1847 — by Oken for a mollusk in 1815, by Hiibner for one of the Lepi- 
doptera in 1816, and by Haan for a crustacean in 1835. The less 
correct form Egle was itself employed for one of the Diptera by 
Robineau-Des\oidy in 1830. It is therefore necessary to use Cyclo- 
pyge, Corda's type, Cyclopyge megacephala, being the same species as 
Barrande's FajIc rediviva. Since Aeglina has to disappear, we can no 
longer use Pictet's family name Aeglinidae, and it may be replaced, 
as is natural, by Cyclopygidae. 

Bohemia is of course the center of development of Cyclopyge, for 
there are eight species, occurring in the shales at the top and bottom 
of the Ordovician. 



64 bulletin: museum of comparative zoology. 

In D — di are: Cydopyge speciosa (C'orda) (type of his genus Miero- 
paria), C. prisca (Barrande), C. sulcata (Barrande), C. princeps 
(Barrande), and C. rediviva (Barrande). In D — ds, at the top of the 
Ordovician, Cydopyge speciosa, C. sulcata, and C. rediviva, and also 
C. (jigantea (Barrande), C. pachycephaki Corda, and C. armata (Bar- 
rande) occur. 

Examples of six of these species, including the types of C. princeps 
and C. prisca, are in M. C. Z., and in studying them one is struck with 
the fact that although all have very large eyes, there is a certain 
amount of variation in the size of the eye in proportion to the size of 
the cephalon. It reaches its maximum in C. armata, and the minimum 
in the associated C. gigantea. In several species, especially in C. 
gigantea and C. sulcata, there is an appreciable width of fixed cheek 
behind the eye, and in C. princeps the eyes are far apart in front. 

Although there is this variation in the size of the eyes, it seems as 
though the culmination of trilobite eye expanse in Cydopyge armata 
Barrande and C. suharmata Reed should be recognized by allotting to 
them a generic name of their own. In addition to having the fixed 
cheeks reduced to a mere vestige, the free cheeks entirely given up to 
the visual surface and uniting in front, these species have an Ampyx- 
like frontal spine, and the glabella is marked by two pairs of deeply 
impressed furrows. Other species have more or less of a development 
of glabellar furrows, but where the surface is not smooth, there is 
usually only one pair of furrows well developed in species other than 
those now referred to the new genus Symphysops. 

The genera of the Cyclopygidae are : — 

Cydopyge Corda. Eyes very large, but some remnant of fixed 
cheek always present behind them. Palpebral lobes narrow, bordering 
the dorsal furrows. Thorax with six segments. Pygidium short and 
wide. Type: — Egle rediviva Barrande. Ordovician, Bohemia, Scan- 
dinavia, and British Isles. 

Symph.N'sops, gen. nov. Eyes meeting in front, so as to form a con- 
tinuous band around sides and front of cephalon. Glabella produced 
into a spine in front, and marked by two pairs of furrows. Type: — 
Aeglina armata Barrande. Upper Ordovician, Bohemia, and Scotland. 

Telephus Barrande. Palpelbral lobes separated by convex fixed 
cheeks from dorsal furrows. Pygidium short and narrow. Type: — 
Tdephus fractus Barrande. Ordovician, Bohemia, Scandinavia, 
British Isles, North America. 



RAYMOND: ORDOVICIAN TRILOBITES. 65 



Telephus Barrande. 

In an interesting paper on this prexiously obscure genus, Dr. 
Hadding (Geol. foren. Forhandl, 1913, 35, p. 25, pi. 1, 2) gives a sum- 
mary of the important characteristics, as compared with the other 
long-eyed trilohites, Aeghna and Remopleurides. He came to the 
conclusion that each of these genera represented a distinct family. 
Although Aeglina (Cyclopyge) and Remopleurides are rather obviously 
only distantly related, it seems to be justifiable to put Telephus in the 
Cyclopygidae. In both Telephus and Cyclopyge the eyes are very 
large, the glabella is broad, long, and glabellar furrows are modified or 
absent. The chief difference between the cephala of the two genera 
is that in Cyclopyge the palpel)ral lobes adjoin the dorsal furrows, 
whereas in Telephus the fixed cheek intervenes. Hadding himself 
agrees that the thorax of Telephus, so far as it is known, offers no diffi- 
culties, and that the pygidium, though small in Telephus, is structur- 
ally similar to that of Cyclopyge. Hadding's statement that palpebral 
lobes and fixed cheeks are absent in Aeglina requires some modifica- 
tion. The palpebral lobes are certainly \ery narrow, but they are 
present, and the posterior portion of the fixed cheek is visible in well- 
preserved specimens of most species, and conspicuous in some. 1 
presume in his statement he had reference only to the part of the fixed 
cheek between the dorsal furrow and the palpebral lobe. 



Telephus americanus Billings. 

Telephus americanus Billings, Pal. foss. Canada, 1865, 1, p. 291, fig. 281. 
Hadding, Geol. foren. Forhandl., 1913, 35, p. 41, fig. 1, pi. 1, fig. 11. 

Hadding published a new figure of the type of this species and 
* brought out the principal characteristics of the cranidium much better 
than was done at the time of the original description. With a number 
of specimens before me 1 can only again call attention to the highly 
convex glabella with its pustulose surface and the pair of obscure 
depressions representing the posterior pair of glabellar furrows. A 
small pustule takes the place of the nuchal spine possessed by most 
species of this genus. One of Hadding's most important results was 
to show that the so-called spines on the front of the cranidium were 
really only the buttresses at the anterior ends of the eyes. 

A number of fragmentary free cheeks from Table Head, Nfld., prove 
to be entirely similar to the Swedish ones described by Hadding. 



66 bi'LLEtin: museum of comparative zoology. 

Below the visual surface of the eye is a narrow but deep groove, and 
outside that a thick elevated border. At the angle is the base of a 
small spine, but in no case does it seem to be preserved. 

Horizon and Locality: — Billings's specimens were from division N, 
Table Head and Pistolet Bay, and division P, Portland Creek, Nfld. 
Professors Schuchert and Twenhofel collected numerous cranidia and 
cheeks from zones M2, Ni, N2, and N3, and from the Isolated limestone, 
all at Table Head, Xfld. 

Near the base of the Athens at Saltville, Va., there occur specimens 
of a large Telephus 'which is too poorly preserved to be positively 
identified. 

Telephus troedssoni, sp. nov. 

Cranidium small, moderately convex, with broad, flaring palpebral 
lobes which enlarge toward the front. Glabella ovate, tapering con- 
siderably toward the front, bearing only one pair of furrows, which are 
obliquely directed depressions which do not connect with the dorsal 
furrows. The nuchal ring is wide, and bears a long slender median 
spine. The specimen is a cast of the exterior, and shows a very fine 
granular ornamentation on the palpebral lobes. 

Measurements: — The cranidium is 4.00 mm. long, and 5.00 mm. 
wide across the palpebral lobes near the front. The glabella is 2.25 
mm. long, and 3.00 mm. wide at the base. The nuchal spine is about 
1.25 mm. long. 

This species appears to be most closely allied to Telephus mobergi 
Hadding (Geol. foren. Forhandl., 1913, 35, p. 37, pi. 2, fig. 12-17), 
agreeing with that species in the possession of one pair of glabellar 
furrows, which, however, are differently placed, and in having orna- 
mentation only on the palpebral lobes. 

T. troedssoni differs from T. americanvs Billings in that the glabella 
tapers more rapidly forward, and in possessing a nuchal spine. 

Horizon and Locality: — A single cranidium was found by the writer 
in Athens shale associated wath Nemagraptus gracilis in a cutting on 
the railroad two miles northeast of Athens, Tenn. Named for Dr. 
Gustav Troedsson who was with me when the specimen was found. 
Holotype (M. C. Z. 1,723). 

Styginidae Raymond. 

Approximately isopygous Opisthoparia with glabella greatly ex- 
panded at the front, anterior portions of the facial sutures widely 



RAYMOND : ORDOVICIAN TRILOBITES. 67 

di\ergent, eyes typicall\- very far back. Thorax of nine segments 
in the topical genus. Pygidium with well-defined, long axial lobe, 
pleural lobes smooth or with faint furrows. 

Stygina Salter. Glabella only faintly outlined, withoutjurrows. 
Eyes close to posterior margin. Type:— Stygina latifrons (Portlock). 
Ordovician, Scandinavia, and British Isles. 

Broxteopsis Nicholson and Etheridge. Glabella strongly outlined, 
with or without three pairs of furrows. Eyes close to posterior margin. 
Type: — Bronicopsis scotica Nicholson and Etheridge. Ordovician, 
Sweden, Great Britain, and eastern North America. 

HoLOMETOPUS Angelin. Glabella strongly outlined. Eyes about 
their own length from the posterior margin. Type: — Holometopus 
limhahis Angelin. Lower Ordovician, Scandinavia, and eastern North 
America. 

Stygina Salter. 

This Ordovician genus, found principally in the British Isles, was 
included under the Asaphidae by Salter (Palaeontogr. soc, 1864, 
(1866), p. 171, pi. 18) but with the comment that it showed character- 
istics which made it transitional between "Asaphus" and "lllaenus." 

Among the peculiarities of the genus are: — Glabella not strongly 
outlined but much expanded at the front, extending almost to the 
anterior margin. Facial sutures far apart at the front. Free cheeks 
wnde. Eyes small and very far back. Thorax with nine unfurrowed 
segments. Pygidium with ringed axial and smooth pleural lobes. 

The presence of nine unfurrowed thoracic segments excludes this 
genus from the Asaphidae as now restricted, and the form of cephalon 
and pygidium prevent its assignment to the lllaenidae. The form of 
glabella, the free cheeks, and position of the eyes, suggest the Goldi- 
idae, but the axial lobe of the pygidium is too long and the pleural 
lobes too smooth to meet the requirements of that family. For tri- 
lobites of this type, with a Goldius-like cephalon and an asaphid-like 
pygidium, the family Styginidae was erected. 

Holometopus Angelin. 

When he proposed this genus, Angelin (Pal. Scandinavica, 1854, 1, 
p. 58, pi. 33) described three species, which he arranged in alphabetical 
order. Since the first two were described from pygidia only, it is 
e\-ident that he had in mind the third as the typical form, since his 
description of the cephalon could have been taken from that one only. 



68 bulletin: museum of comparative zoology. 

1 therefore designate the third species, Holometopvs limbatus, as the 
type of the genus. 

Holomdopus limbatus differs from Stygina in ha\ing the glaljella 
strongly raised above the cheeks and in having the e\"es farther forward. 
This is a rare species and 1 have not seen a specimen. From exidence 
of alhed species 1 should be inclined to doubt the correctness of the 
position of the eyes in Angelin's figure, were it not for his definite 
statement "Oculi modici, semilunares, distincte reticulati, subcen- 
trales." 

Holometopus limhafus was found in the Orthoceras limestone (Upper 
Beekmantown) at Fagelsang, near Lund, in Scania, Sweden. Billings 
(Pal. foss. Canada, 1862, 1, p. 95, fig. 85) described a very similar 
species, Holomdopus angelini, from the limestone in the upper part 
of the Levis, at Point Levis, Que. 



Bronteopsis Nicholson and Etheridge. 

Bronteopsis Salter nomen nudum (Wj'ville Thomson Mss.), Palaeontogr. soc, 

1864 (1866), p. 143. 1883 (1883), p. 216. 
Bronteopsis Nicholson and Etheridge, Mon. Silur. foss. Girvan, 1879, p. 157, 

pi. 11, 12. Reed, Palaeontogr. soc, 1904, 58, p. 92, 1914, 68, p. 26, pi. 4. 

This genus was proposed in manuscript by \V\'\ille Thomson for a 
trilobite from the Girvan district of Scotland, and referred to without 
reference to any type-species by Salter. It was first published by 
Nicholson and Etheridge, who described one new species, Bronteopsis 
scotica, which becomes the type. 

Bronteopsis is very like Stygfna, but has a much more strongly 
outlined glabella and a shorter p\'gidium. It differs from Holometopus 
chiefl\' in ha^■ing the eyes farther back, in the position of those of 
Stygina. 

Salter, Nicholson and Etheridge, and Reed, all considered this genus 
closely allied to Bronteus (Goldius) and ha\-e placed the genus in the 
Bronteidae (Goldiidae). The p\gidium is, howe\er, so unlike that of 
Goldius and both cephalon and pygidium are so like those of Stygina, 
that Bronteopsis can be much more satisfactorily placed with the 
latter genus than the former. The Styginidae are howexer probably 
more closely allied to the Goldiidae than to the Asaphidae. 

Holometopus and Bronteopsis are closely allied and 1 am not \et 
sure they should be separated. Since there are, howe\er, two species, 
H. limbatus Angelin and H. angelini Billings, which ha\-e their eyes a 



RAYMOND: ORDOVRIAN TRILOBITES. 69 

little farther forward than in Bronteopsis, it may be as well to keep 
the genera apart. Sueh a form as Holonirtopiis uifoi.s Wiman must 
certainl\- be transferred to Bronteopsis. 

Bronteopsis scotica Nicholson and Etheridge. 

Bi-onieopsis scotica Nicholson and Etheridge, Men. Sihir. foss. Girvan, 1879, 
p. 167, pi. 10, fig. 21, 22, pi. 11, fig. 1-4. Reed, Palaeontogr. sec, 
1904, 58, p. 94, pi. 13, fig. 5-13. 

A single imperfect cranidium appears to represent this species. It 
differs from Bronteopsis grcgaria and agrees with B. scotica in having 
three pairs of glabellar furrows represented by pits, and also has a pair - 
of prominent eye-lines situated unusually far back. The posterior 
pair of glabellar furrows have the same position and shape as those of 
B. scotica, but are much less deeply impressed. 

Measurements: — The cranidium is 10 mm. long; and the anterior 
portion of the glabella is 7 mm. wide. 

Horizon and Locality: — The single cranidium was collected by 
Professors Schuchert and Dunbar from the Normanskill, one mile from 
the Dominion Iron and Steel Company's quarries at Agathuna, New- 
foundland. The Scottish specimens are found in the Balclatchie 
group (Llandeilo) of the Girvan district of Scotland. 



Bronteopsis gregaria Raymond. 
Plate 3, fig. 12-14. 

Bronteopsis gregaria Raymond, Bull. M. C. Z., 1920, 64, p. 283. 
Holometopus angelini Billings (partim), Pal. foss. Canada, 1865, 1, p. 281, 
Hon, p. 95, fig. 85. 

( ranidium much expanded at the front, so that it is wider than long. 
Glabella convex, prominent, expanded at the anterior end, the width 
there being equal to about three fourths the length. The glabella 
tapers rapidly toward the narrowest place, at the neck-ring, and has an 
ol)scure median carina on its posterior half. In the dorsal furrows are 
obscure indications of three pairs of pits, one pair close to the anterior 
margin and two pairs on the constricted "neck" of the glabella, these 
being Aestigial glabellar furrows. The fixed cheeks form wide flat- 
tened bands on either side of the glabella and opposite its narrow part 
are raised nearly or quite as high as the glabella itself. The neck-ring 
liears a small median tubercle. 



70 bulletin: museum of comparative zoology. 

Pygidium approximately semicircular in outline, convex, with a 
narrow concave border. Axial lobe long, the acutely tapering posterior 
end continuing, though only faintly raised, to the border. At the 
anterior end of the axial lobe are three well-defined rings, behind which 
there are two or three rather obscure ones. The pleural lobes are 
smooth, except for an anterior rib. The smaller specimens are nearly 
flat, and the posterior portion of the axial lobe is more clearly defined 
than in the large ones. 

Measurements: — Length cranidium 7.5 mm., width at front 9 mm. 
Width glabella at front 5.5 mm., at neck-furrow 3.5 mm. Length 
pygidium 4 mm., width 7.5 mm. 

Horizon and Locality: — The types are from the base of the Liberty 
Hall limestone at Lexington, Va., where the species is common. It 
is also common at the top of the Holston at the Thomas farm, three 
miles northeast of Blacksburg, \a., in the Athens at Chatham Hill, 
on the northern slope of Walker Mountain, north of Marion, Va. 
A single specimen was found above the middle of the Holston on the 
Hoge farm, seven miles soi*th of Bland, Bland Co., Va., and another 
single specimen in the middle Ottosee, seven miles north of Mendota. 
Specimens from these three localities are in entire agreement. In 
Tennessee 1 found it at onh' one localitv, between the Holston and 
TelHco, in South Knoxville. 

In Newfoundland Schuchert and Twenhofel found this species in 
zones M2, Ni, and the Isolated limestone, all at Table Head. These 
specimens dift'er from the ones described above in having the cranid- 
ium a little shorter and broader, the posterior part of the glabella 
a little wider, and a slightly shorter axial lobe on the pygidium. 
Specimens nearer these than the other Virginian specimens were 
collected by Dr. Shuler on the northern side of Walker Mountain, 
near White Gate, Bland Co., Va. 

This species is much more nearly related to Bronteopsis ardmilla- 
nensis Reed than to the type of the genus. The Scottish species has 
a slightl\' ditt'erent confoi-mation of the fixed cheeks and more traces 
of ribs on the pleural lobes of the pygidium, but the differences between 
the two species are small. B. nitens Wiman, obtained from boulders 
of the older Chasmops limestone, has a somewhat wider glabella 
and a more acutely triangular axial lobe on the pygidium. Cotypes 
(M. C. Z. 1,595-1,597). 

Bronteopsis marginata, sp. nov. 

This species is closely allied to B. gregaria, differing from it in having 
a broader concave border in front of the glabella, and a less strongly 



RAYMOND: ORDOVICIAN TRILOBITES. 71 

delimited glabella, which is less constricted toward the back. The 
pygidium is proportionately shorter. 

Measurements: — An imperfect cranidium, the holotype, is 6 mm. 
long, and the border in front of the glabella 2 mm. wide. A pygidium 
is 3 mm. long, and 6.5 mm. broad. 

Horizon and Locality: — A rare fossil in a boulder in the conglomer- 
ate on lot 22, concession VI, two miles north of Mystic, Que., where it 
is associated with Normanskill fossils. Holotype (M. C. Z. 1,759). 

Bathyuridae Walcott. 
Bathyurellus Billings. 

Bathyurellus is a genus seldom met with, although thirteen species 
have been described. It is of some interest because it is one of the few 
genera common to the Beekmantown and Chazy, and found both in 
conglomerates and in situ in Newfoundland, Quebec, and New York. 

Billings did not designate a type for the genus, but since he described 
all parts, and had complete specimens of B. nitidus only, it seems 
entirely proper to select that species as the type. 

Bathyurellus abruptus Billings. 

Plate 3, fig. 18. 

Bathyurellus abruptus Billings, Pal. foss. Canada, 1865, 1, p. 263, fig. 247, 250. 

Schuchert and Twenhofel collected several cranidia and pygidia of 
this species near the lobster factory at the head of the bay at Old Port 
au Choix, Nfld. The cranidium is very readily recognized, because the 
glabella is long and descends abruptly into the very narrow concave 
border. The surface markings, consisting of fine cracks arranged 
concentrically on the glabella, are also characteristic. The palpebral 
lobes are very large. 

One small cranidium has a pair of faint glabellar furrows which 
reach the dorsal furrows at the anterior ends of the palpebral lobes. 

Lying beside one of the pygidia is a long, narrow, oval hypostoma, 
which probably belongs to this species. The surface is evenly convex, 
and the maculae but little behind the middle. 

The pygidium assigned to this species is a very peculiar one, and 
there seems to be no evidence that they belong together other than the 
fact that they occur in the same lasers in fairly equal numbers and 
have similar surface markings. 

The anterior lateral angles are truncated, the pygidium is longer 



72 bulletin: museum of comparative^ zoology. 

than wide, and is concave only on a small part of each pleural lobe, all 
characteristics in which this species departs from the typical Bathyu- 
rellus. If the pygidium were more convex, it would somewhat suggest 
that of Hyboaspis, a fact which may throw some light on the relation- 
ships of that genus. 

Horizon and Localiti/: — Billings's specimens were from divisions 
F, G, and H, Port au Choix and Keppel Island, Xfld. Schuchert and 
Twenhofel obtained it from two zones 3100-2 and 3100-3 at Old Port 
au Choix, where it occurs in the Beekmantown with Pctigurus new, P. 
timon, and Bathyurellus margi)iatus. 

Bathyurellus :\l\rginatu8 Billings. 
Bathyurellus marginatus Billings, Pal.rfoss. Canada, 1865, 1, p. 264, fig. 248. 

This species occurs at the same horizons and in the samvT localities 
as the last, but is more rare. Billings had but one cranidium, and 
Schuchert and Twenhofel found but one, a very small specimen. 
Pygidia are absolutely unlike those assigned to the associated B. 
abruptus, and are not concave. BathyurcUus expansus Billings, from 
Stanbridge, has a pygidium which is similarly ribbed, but the axial 
lobe is wider and the surface outside it is largely concave. 

Bathyurellus validus Billings. 
Bathyurellus validus Billings, Pal. foss. Canada, 1865, 1, p. 268, fig. 252. 

Billings says that the glabella and fixed cheeks of this species are 
like those of B. fraternns and that the genal angles are prolonged in 
broad flat spines as in B. formosiis. The genal spines of B. fratermis 
are also broad, but they appear to stand nearly at right angles to the 
body, and only the narrow brim is approximately flat. The pygidium 
is similar to that of B.fratcrnus, but lacks the ribs on the pleural lobes. 

Horizon and Locality: — The original locality was in division L at 
Point Rich, Nfld. Schuchert, Twenhofel, and Dunbar found isolated 
pygidia at Port au Choix, Port Rich, and, the highest point in itg range, 
the Leperditia bed at Port au Port. Hyatt collected a pygidium at the 
first point north of Port au Port, Nfld. 

Bathyurellus nitidus Billings. 

Bathyurellus nitidus Billings, Pal. foss. Canada, 1865, 1, p. 265, fig. 249. 

Bathyurellus tiitidus, B. formosus, B. fraternus, and B. validus are 
very much alike. B. nitidus may be recognized by the fact that, like 



RAYMOND: OEDOVICIAN TRILOBITES. 73 

B. abrupius, it has a long glabella which reaches the concave border. 
The glabella is much more pointed than in the former species, and is 
not nearly so convex, especially at the anterior end. Genal spines are 
said to be absent. The pygidium is like that of B. fratcnius, in that it 
shows two or three pairs of ribs on the pleural lobes, but the axial lobe 
is somewhat shorter. 

Horizon and Locality: — This species has been found only at the 
type-locality in the pebbles of the conglomerate at Cow Head. Schu- 
chert and Dunbar found only a cranidium and a p\gidiuni. 

Bathyurellus formosus Billings. 
Bathyurellits formosus Billings, Pal. foss. Canada, 1865, 1, p. 266, fig. 250. 

Bathyurellus formosus has a shorter glabella than B. nitidus, and 
differs from both B. fraternus and B. validus in that the anterior part 
of the glabella is more convex, and the dorsal furrows are straight 
lietween the eyes. One tiny cephalon, which, with the genal spines, is 
only 2.5 mm. long, has the same short, elevated glabella, narrow brim, 
and long genal spines as the adult. Billings states that in this species 
the eyes are smaller than in B. nitidus, but this does not seem to be a 
constant characteristic. The cranidium of B. viarginatus has an even 
narrower brim than B. foruiosus, and a wider cheek-roll in front of the 
glabella. 

Horizon and Locality: — Like the last, this species has been found 
only in the pebbles of the conglomerates at Cow Head, Nfld. Schu- 
chert and Dunbar collected three cranidia. 

Bathyurellus fraternus Billings. 

Plate 3, fig. 19. 

Bathyurellus fraternus Billings, Pal. foss. Canada, 1865, 1, p. 267, fig. 251a, b. 

Entire body ovate, broadest at the head, the thorax enclosed by the 
long genal spines. Cephalon large, broad, evenly convex, with a 
narrow, concave brim which extends back along the genal spines. The 
latter are continued nearly or quite to the end of the pygidium. The 
glabella is elevated but slightly above the general surface, pointed in 
front, outlined by shallow cur\ed dorsal furrows which bend slightly 
inward between the eyes. The palpebral lobes are large, slightly 
convex, but proportionately smaller than in B. formosus. The cheeks 
are wide, and curved abruptly downward from the eyes. 



74 bulletin: museum of comparative zoology. 

The thorax consists of nine segments. The axial lobe is strongly 
convex, a little more than one third the total width, and tapers con- 
siderably from front to back. The pleural lobes are flat, and, what is 
most remarkable, turn slightly upward instead of downward at the 
sides, so that the concavity which is so characteristic a feature of the 
pygidium extends to the thorax as well. 

The segments are very flat, and each bears a shallow median furrow 
on the outer portion. 

The pygidium is nearly semicircular, the axial lobe broad, depressed, 
convex, the remainder concave. There are four rings on the axial 
lobe, and three pairs of broad ribs on the pleural lobes, none of them 
very strongly marked. The under surface, where exfoliated, seems to 
be coarsely punctate. 

Measurements: — The specimen, with the head bent somewhat down- 
ward, is 48 mm. long. The cephalon, on the axial line, is 25 mm. long; 
the thorax 18 mm.; and the pygidium 14 mm. The greatest width of 
the thorax is at the third segment, where it is 29 mm. wide. The axial 
lobe is 13 mm. wide at the anterior end of the thorax, and 9 mm. wide 
at the front of the p\'gidium. The pygidium is 24 mm. wide at the 
front; and the axial lobe is 9 mm. long. 

Bathyurellus fraiernus differs from B. nitidus not only in having a 
less elevated glabella with a cheek-roll between it and the brim, but 
also in having a much wider axial lobe on the thorax. B.formosus has 
a more convex glabella, and B. expansus has a more convex glabella 
and more ribs on the pygidium. 

Bathyurellus validus and B. fraternus are almost identical. Billings 
separated them chiefly l>ecause he thought that B. fraternus came from 
an horizon 2,000 feet above that of B. validus, but as B. fraternus was 
obtained from pebbles in a conglomerate, that argument has no force. 
Since B. validus is not yet known from entire specimens, and since the 
two species can be separated by the greater smoothness of the py- 
gidium of the latter, both may for the present be recognized. 

Horizon and Locality: — The original specimens were from the 
pebbles in the conglomerates at Cow Head, Nfld. Schuchert and 
Dunbar collected a single cranidium there, and Hyatt obtained the 
entire specimen (M. C. Z. 1,643), described above, on the west side of 
Gargamella Cove, near the base of the Chazy. 



RAYMOND: ORDOVICIAN TRILOBITES. 75 

Bathyurellus expansus Billings. 
Bathyurellus expansus Billings, Pal. foss. Canada, 1865, 1, p. 318, fig. 306a, b. 

The cranidium of this species closely resembles that of B. formosus, 
as both have a con\ex glabella and a cheek-roll between the front of it 
and the concave brim. In B. expansus, however, the roll is consider- 
ably wider than in the former species. On the pleural lobes of the 
pygidium there are fom* pairs of rather distinct broad ribs. 

Horizon and Localiiy: — The original specimens were from lot 20, 
concession VI, in Stanbridge, Que. ; the species is quite common on lot 
22 of the same concession. Schuchert and Dunbar found one cra- 
nidium in the conglomerate at Cow Head, Nfld. 

Bathyurellus brevlspinus Raymond. 

Bathyurellus brevispinus Raymond, Ann. Carnegie mus., 1905, 3, p. 337, pi. 10, 
fig. 13-15. 7th rept. Vermont state geol., 1910, p. 218, pi. 32, fig. 13-15. 

This trilobite was described from cephala only, but when collecting 
at the typical locality recently 1 found a single cranidium associated 
with three pygidia which very probably pertain to this species. 

Pygidium semicircular, depressed convex, the width of the concave 
border equal to one third the length. Axial lobe narrow, convex, dis- 
tinctly raised and outlined at the posterior end. Its surface shows 
two distinct and two faintly marked rings. The inner moities of the 
pleural lobes are low, nearly flat-topped, sloping abruptly into the flat 
border. There are three pairs of broad ribs beside the half ribs at the 
front, so that the whole surface, except directly back of the axial lobes, 
is involved. 

In the original description this species was compared with Bathy- 
urellus forinosits. The pygidium of that species is not yet known. 
So far as can be judged from the present material, B. brevispinus would 
appear to be intermediate in characteristics between B. frafern'us and 
B. expansus, having the pygidium more strongly ribbed than the 
former and less so than the latter. 

Measurements: — The largest pygidium is 6 mm. long, 12 mm. wide; 
and the axial lobe is 4 mm. long. The smallest is 3 mm. long, and 
has more sharply marked rings and ril)s and a slightly narrower 
border than the large specimen. 

Horizon and Locality: — All the specimens so far collected have come 
from the reef at the base of the Upper Chazy in a pasture three miles 
southeast of Chazy, N. Y., near Little Monty Bay. 



76 bulletin: museum of comparative zoology. 



Bathyurellus glensaulensis Reed. 

Bathyurellus glensaulensis Reed, Quart, journ. Geol. soc. London, 1910, 66, 
p. 274, pi. 21, fig. la-3b. 

This, the only extra- American species yet described, is most closely 
allied to B. crpansus so far as can be determined from the known char- 
acteristics of the two species. The Irish form combines a very wide 
cheek-roll with a relatively short and prominent glabella. The genal 
spines are short like those of Batfuiurcllus brrvispinus Raymond, \mt 
the latter species has a narrow cheek-roll, like B. formosus. 

Horizon and Localiiy: — This species has been found only in a' cal- 
careous ash on the Glensaul River, near Garranagerra, County Galway, 
Ireland. 

AsAPHiDAE Emmrich. 

Ogygiocariniae Raymond. 

NiOBE quadraticaudata (Billings). 

Plate 3, fig. 20. Plate 6, fig. 13. 

Asaphus quadraticaudatus Billings, Pal. foss. Canada, 1865, 1, p. 272, fig. 258. 
Asaphus morrisi Billings {partim), Ibidem, p. 272, fig. 257. 

Billings knew only the pygidium of this species, but collected also 
specimens of the hypostoma, which he supposed to belong to his 
"Asaphus" morrisi. Professors Schuchert and Twenhofel collected, 
among other specimens, one nearly complete, which shows clearly that 
this is a Niobe. 

Entire test elongate, subrectangular, tapering but little. 

Cephalon longer than thorax or pygidium, uniformly convex, highest 
along the median line of the glabella. Glabella large, long, smoothly 
convex, without furrows. It is nearly parallel-sided, Init expands a 
little in front of the eyes. At the base is a pair of long lunate elevations. 
The eyes are situated close to the glabella, from which the palpebral 
lobes are hardly separated. They are well forward, as usual in the 
genus, a trifle more than their own length from the posterior border. 
At the horizon of the posterior ends of the eyes there is a small median 
pustule. Some exfoliated specimens show traces of three pairs of 
glabellar furrows. Free cheeks wide, striated, the outer part of the 
slope concave. Just below the visual surface of the eye is a narrow 
concentric step-like fold of the shell, which is so peculiar as to make 



RAYMOND: ORDOVICIAN TRILOBITES. 77 

detached free cheeks readily recognizable. In front of the glabella the 
border is somewhat convex and the anterior margin curved downward. 
The entire surface of the cephalon, but more especially the glabella, 
is covered with wa\y cracks and elevated lines, and very numerous 
large and small puncta. 

Thorax of eight segments. Axial lobe a little more than one third 
of the total width. Pleural lobes with narrow diagonal furrows. The 
segments are ornamented with numerous cracks and small puncta 
arranged parallel to the axis of the animal. 

Outline of the pygidium suggestive of quadrangularity, but smoothly 
rounded. Axial lobe wide, gently convex. Pleural lobes depressed 
convex, with wide conca\'e border. The axial lobe has a single ring 
and the pleural lobes a single pair of ribs. The ornamentation consists 
of numerous irregular cracks arranged more or less parallel to the outer 
margin. 

The specimens of this species are accompanied b;s' a number of 
hypostomata which are evidently the same as described by Billings as 
the hypostoma of Asaphus morrisi. These not only show b\' their 
form that they belong toNiobe, but their surface markings prove that 
they belong to the species now under discussion. The hypostoma is 
long, rudely rectangular, the surface slightly convex, and the narrow 
wings expand forward. The posterior margin has a shallow notch, 
forming two short broad lobes. In front of the notch is a deep trans- 
verse furrow, and in front of that a pair of deep maculae. Surface 
covered with deep, somewhat irregular, transverse cracks. 

Measurements! — Length of entire specimen about 65 mm.; width at 
genal angles 35 mm.; length cephalon, about 23 mm.; length thorax 
21 mm.; width axial lobe at front 13 mm.; length pygidium 21 mm., 
width at front 29 mm.; width axial lobe at front 11 mm. Eye 6 mm. 
long. Back of eye 7 mm. from posterior margin of head. A larger 
cranidium is 31 mm. long. The glabella is 16 mm. wide at the neck- 
ring, 20 mm. wide in front of the eyes and the border in front of the 
glabella is 3 mm. wide. An hypostoma is 14 mm. long, and 11 mm. in 
greatest width, near the posterior end. A larger hypostoma is 19 mm. 
long, and 17 mm. wide. 

Niobe laeviceps Angelin is a species which has the pygidium as smooth 
as that of the form just described, but both cephalon and pygidium are 
shorter. Niobe lindstrdmi Schmidt has a cephalon very like that of N. 
quadrafieavdata, and the p\'gidium is nearly as smooth, but has several 
rings on the lobe and it lacks the characteristic surface markings. 
Most other species of Niobe have ribs on the pygidium. 



78 bulletin: museum of compaeative zoology. 

This Newfoundlandian species is, so far as 1 can learn, the last 
survivor of the genus. 

Typically a basal Ordovician genus, species of Niobe are found in the 
Ceratopyge "Region" of Sweden and Norway, the Tremadoc of Great 
Britain and France, the Orthoceras limestone, "Regio C" of Scandi- 
navia, and the equivalent beds in Russia. It has not beeti reported in 
any of these countries from strata younger than the American Beek- 
mantown. 

Horizon and Locality: — Billings's original specimens were from di- 
vision N, Table Head, and the conglomerates of P, four miles northeast 
of Portland Creek, Nfld. Professors Schuchert and Twenhofel found 
it a common fossil in their zones M2, Ni, and the Isolated limestone at 
Table Head, and also obtained one specimen from zone N2 at the same 
locality. All these localities are in strata of Normanskill age. 

Niobe morrisi (Billings). 
Plate 6, fig. 10. 
Asaphus morrisii Billings (partim), Pal. foss. Canada, 1865, 1, p. 272, fig. 257. 

Approaching the subject from an American viewpoint, 1 had sup- 
posed Asaphis morrisi, of which pygidia only are surely known, to be a 
Basilicus, but the study of specimens collected by Schuchert and 
Twenhofel convinces me that it is really a Niobe of the type of N. 
emargvnula Angelin. Specimens of this species do not appear to be 
common. 

In the absence of more complete material the generic reference is of 
course in some doubt. The general appearance of the pygidium, with 
its broad form and ill-defined ribs, is rather that of Niobe than Basilicus. 

The axial lobe is broad at the front, tapers regularly and extends 
back to the posterior margin, though it is but faint where it crosses the 
concave portion. It usually shows but two well-defined rings and two 
partially developed ones. One specimen in the present collection 
shows seven rings, and Billings said there were ten obscure rounded 
rings on the type. The pleural lobes show four or five pairs of broad, 
rounded, rather obscure ribs. 

The surface markings are striking and characteristic. The whole 
surface is finely punctate, and also marked by a system of short wavy 
cracks which approximately parallel the posterior margin. These 
cracks are absent from the furrows between the ribs and from the dorsal 
furrows. On the doublure the terrace lines are very strongly developed. 



eaymond: ordovician trilobites. 79 

Billings assigned to this species the hypostoma which 1 have de- 
scribed above as probably belonging to Niobe quadraticaudata. It is 
undoubtedly the hypostoma of a Niobe, but not having seen it in place, 
there is still some question as to whether Billings may not have been 
correct in his disposition of it. 1 have assigned it to the former species, 
because, first, there can be no doubt but what that species is a true 
Niobe, and secondly, because 1 find that hypostoma associated with 
shields of X. qxiadraticamlata in localities which have not so far pro- 
duced pygidia of X. morrisi. There are, however, indications that 
some of the cranidia, free cheeks, and hypostomas now referred to N. 
quadraticaudaia really belong to N. morrisi. For instance, there is one 
hypostoma from zone Ni, Table Head, which has much less prominent 
striae than the others. This might belong to X. morrisi. Some of the 
free cheeks from the same locality not only show the rim-like border 
below the eye but haA'e an elongate tubercle projecting from this rim. 
And lastly, on the same fragment of rock with a pygidium of N. 
morrisi there is a cranidium which seems to have a broader glabella 
and longer and larger basal glabellar lobes than A', quadraticaudata. 
The surface ornamentation is almost exactly the same as on the pygidia 
of N. morrisi, and the surface much more strongly punctate than in the 
shell which remains on the entire specimen of N. quadraticaudata. 

From the above, it is evident that more material is necessary for a 
satisfactory description of this species. 

Measurements: — Billings says: "Width of the largest pygidium 
seen 3| inches [about 87 mm.]; length 2\ inches [about 56 mm.]." 
The largest pygidium in the present collection is 65 mm. wide, and 35 
mm. long. A better preserved one is 49 mm. wide, and 28 mm. long; 
the axial lobe is 12 mm. wide. 

Horizon and Locality: — Billings reported the species from division 
N, Table Head, and the conglomerates of P, four miles northeast of 
Portland Creek, Nfld. Schuchert and Twenhofel collected it only 
from zone Ni at Table Head, but there are two pygidia in the M. C. Z. 
(1,649, 1,650) collected by Professor Hyatt on the east side at Port au 
Port. All are from the horizon of the Normanskill. 

Niobe lineolata, sp. nov. 

Plate 3, fig. 15, 16. 

Test small, nearly parallel-sided. Cephalon almost semicircular in 
outline, the genal angles extended into short but sharp spines. Gla- 
bella depressed convex, smooth, nearly parallel-sided, expanding but 



80 BULLETIN : MUSEUM OF COMPARATIVE ZOOLOGY. 

little in front of the eyes. Neck-furrow very faintly indicated on the 
median lobe. Just ahead of it is a minute median pustule. No traces 
of glabellar furrows. Eyes very large, nearly one half the whole 
length of the cephalon. Facial suture marginal in front. A narrow 
flat border extends around the front of the glabella. The posterior end 
of the hypostoma is rounded, but details cannot be made out. Thor- 
acic segments short, axial lobe ele\ated above the pleural lobes, nar- 
row, less than one third the total width. 

Pygidium semicircular in outline, with a narrow concave border. 
Axial lobe prominent, tapering regularly backward to a point at the 
posterior margin, depressed and faint where it crosses the concave 
border. On it are four to eight faintly defined rings. The pleural 
lobes show four pairs of rounded ribs which extend down onto the 
conca^•e portion. 

The surface on all parts is covered w^ith very fine raised wavy lines. 

Measurements: — Length of a nearly complete specimen 20 mm.; 
width at front of thorax 14 mm., length of thorax 7 mm.; length of 
pygidium 7 mm., width 14 mm. Length of another cephalon 6 mm., 
width 12 mm. 

A specimen from Portau Port is 21 mm. long, and 13.5 mm. wide. 
The cranidium is 8 mm.; the thorax 6 mm.; and the pygidium 7 mm. 
long. A large pygidium is 10.5 mm. long, and 19 mm. wide. 

Horizon and Locality: — This species is most common at Port au 
Port where Schuchert and Twenhofel collected it in their zone 6 
(Normanskill) and where Professor Hyatt also obtained a large num- 
ber of specimens. Professor Hyatt obtained it also from the same 
horizon on the south side of St. John Island. There is a single p}'gid- 
ium in the Yale collection from zone Ni at Table Head, and there are 
several cephala, pygidia, and incomplete specimens from zone N2 at 
the same locality. A few specimens were also obtained from the 
Normanskill near the quarry of the Dominion Iron and Steel Company 
at Agathuna, Nfld., by Schuchert and Dunbar. 

The holotype and figured paratype are in the Yale LTniversity Mu- 
seum. Two other paratypes are M. C. Z. 1,760 and 1,761. 

Megalaspis huttoni (Billings). 

Plate 6, fig. 11. 

Asaphus huttoni Billings, Pal. foss. Canada, 1865, 1, p. 271, fig. 256. 

I was at one time of the opinion that the specimens designated as 
Asaphus htdtoni 'were only the young of A. morrisi (see Bassler, Bull. 



i 



RAYMOND: ORDOVICIAN TRILOBITES. 81 

92, U. S. N. M., 1915, p. 102), but with more material it appears that 
they are not only a distinct species, but belong to a different genus. 
The generic reference depends upon: — First, the divided ribs on the 
pleural lobes of the p\gidium; secondly, the similarity to Megalaspis 
pagiata Tornquist; and lastly, the form of the cranidium. 

Cranidium narrow, pointed in front. Glabella depressed convex, 
very narrow between the eyes, expanding in front, definitely outlined. 

Just in front of the ill-defined neck-furrow is a prominent median 
pustule. Eyes small, elevated, situated well back of the middle. 
Fixed cheeks small. Free cheeks and hypostoma unknown. 

Pygidium rounded in outline, more than one half as long as wide. 
Surface rather evenly convex, axial lobe narrow and long, concave 
border narrow. On the axial lobe there are, according to the state of 
preservation, from one to fourteen indistinct rings. On the pleural 
lobes are six to twelve pairs of broad rather indistinct grooved ribs 
which merge into the general surface on the outer parts of the lobes. 

This species is exceedingly like the Swedish and Norwegian M. 
pagiata, differing from it in having the pygidium a trifle more elongate 
and the ribs a little more distinct. 

Megalaspis pagiata occurs in the middle of the Lower Dicellograptus 
beds in Jemtland, Sweden, and in zone 4a, (Ogygia shale), in the 
Mjosen district in Norway. 

Measurements: — Billings's type, a pygidium, was 5 lines (10 mm.) 
long, and 7 lines (14 mm.) wide. A small pygidium in the present 
collection is 11.5 mm. long, and 17 mm. wide. A large one is 43 mm. 
long, and 50 mm. wide. The largest specimen, which is considerably 
flattened, is 50 mm. long, and 78 mm. wide. 

Horizon and Locality: — Billings reported his specimens from division 
N, Table Head, Nfld. Professors Schuchert and Twenhofel seem to 
have found but nine specimens, two in zone Ni at Table Head, five in 
zone No at the same locality, and two in zone b at Port au Port, Nfld., 
all in the Normanskill. 

Xenostegium Walcott. 
Xenostegium Walcott, Smith, misc. coll., 1924, 75, no. 2, p. 60, pi. 13, fig. 5. 

Walcott has suggested this generic name for some of the species 
which have been referred to Megalaspis by American authors. The 
generic diagnosis, "Xenostegium contains many species, some of 
which were formerly referred to Megalaspis. It is characterized by 
the spined pygidium" leaves much to be inferred from the sketchy 



82 bulletin: museum of comparative zoology. 

outline figures. The genotype is Asaphus {Megalaspis f) goniocercus 
Meek, a species hitherto known from p^,'gidia. Walcott figures a 
cranidium, which, if correctly assigned to this species, indicates the 
necessity for the new generic name. Basing the separation on the 
characteristics of the cranidia, Xenostegium differs from Megalaspis 
in lacking the dorsal furrows, so that the glabella is not delimited, and 
in having the facial sutures reach the anterior border at the sides 
instead of meeting at an acute angle on the median line. It is not 
obvious how the cranidium differs from that of Hemigyraspis, which 
occurs at the same horizon and localities as Xenostegium. 



Xenostegium shepardi (Raymond). 
Plate 3, fig. 21. 
Megalaspis shepardi Raymond, Amer. journ. sci., 1922, ser. 5, 3, p. 204. 

Cephalon and thorax unknown. 

Pygidium elongate, subtriangular, pointed behind. Axial lobe 
clearly outlined by the dorsal furrows, but not elevated above the 
general surface; it is contracted near the middle, but as the dorsal 
furrows do not unite behind it, it persists as a median ridge to the pos- 
terior extremity. There are six faintly defined rings on the anterior 
half. Pleural lobes smooth, except for the anterior half rib, and an 
obscurely defined pair just behind it. The shell has numerous, irregu- 
larly scattered, puncta. 

Two other species of this type have been described from western 
North America: — A^. hclemminis (White) and A', gonioccrcvm (Meek). 
The former is the better known, since it has been figured (Rept. U.S. 
geol. surv. west 100th mer., 1877, 4, p. 59, pi. 3, fig. 9). So far as 
can be judged from the figure and description, X. shepardi differs from 
this species chiefly in the contraction of the middle portion of the axial 
lobe, and in having less distinct transverse furrows on both axial and 
pleural lobes. It is also proportionally longer and narrower, as shown 
by the measurements. A", gonioccrcvm is described as almost entirely 
destitute of dorsal furrows, and the axial lobe is said to fade out pos- 
teriorly before reaching the posterior end. It is also wider than long, 
and thus not so slender as A', shepardi. 

Measurements: — The pygidium, which is the holotype (M. C. Z. 
1,685), is 36 mm. long, and 36 mm. in width. The axial lobe is 10 
mm. wide at the front and 6 mm. at the narrowest place. White 
states that a pygidium of A', helemnurus was 15 mm. long to the base 



RAYMOND: ORDOVICIAN TRILOBITES. 83 

of the caudal spine [should add only 1 or 2 mm. to complete, according 
to the figure], and 22 mm. wide. Meek gives the dimensions of a 
pygidium as: length .74 inch (18.5 mm.), width .94 inch (23.5 mm.). 
' Horizon and LocalHj/: — The holotype was collected from the Lower 
Ordovician limestone one eighth mile above the entrance to Sinclair 
Canvon, northeast of Lake Windermere, B. C, by Mrs. Francis P. 
Shepard. 

Hemigyraspis mcconnelli Raymond. 
Plate 3, fig. 22. 

Hemigyraspis mcconnelli Raymond, Bull. 1, Victoria mem. mus., 1913, p. 41, 
pi. 4, fig. 4. 

This species was described from an entire but more or less damaged 
specimen. A pygidium collected by Dr. Francis P. Shepard in some 
measure supplements the original, and is herewith described and 
figured. 

Pygidium almost semicircular, a little more than twice as wide as 
long. Surface depressed convex, with a narrow concave border. 
Axial lobe gently convex, a little less than one third the total width at 
the front, tapering rapidly posteriorly. When ex-foliated it shows four 
poorly defined rings which are probably very inconspicuous in speci- 
mens retaining the test. The pleural lobes show only the faintest 
traces of furrows. 

This species is seemingly very closely allied to H. coUicana, which 1 
described (Ann. Carnegie mus., 1910, 7, p. 41, pi. 14, fig. 9-13) from 
the Lowest Ordovician (Ceratopyge zone) of central Pennsylvania. 
It differs chiefly in having a wider and less distinctly segmented axial 
lobe. 

Horizon and Locality: — The original specimen of this species was 
obtained near Golden, B. C, and the one here figured (M. C. Z. 1,680) 
was collected by Dr. F. P. Shepard in a continuation of the same strata 
(Lowest Ordovician) in Sinclair Canyon, near Lake Windermere, south- 
east of Golden.. 

NiLEUS \L\CROPS Billings. 
NUeits macrops Billings, Pal. foss. Canada, 1865, 1, p. 274, fig. 259. 

Billings stated that Nilem macro ps differed from iV. scrutator in 
having the eye much larger. Although this single characteristic 
suffices to distinguish some of the more typical specimens, it should be 



84 bulletin: museum of comparative zoology. 

pointed out that a more useful flift'erence is that in N. utacrops the 
cranidium is proportionatel\' much longer and narrower than in N. 
scrutator, and the specimens are usuall\' of much smaller size. The 
median tubercle is, in this species, located almost in the middle of the 
head, whereas in N. scrutator it is back on a line with the posterior ends 
of the eyes. 

Measurements: — A large cranidium from Ni is 21 mm. long, and 
23 mm. wide at the palpebral lobes. A smaller one is 10 mm. long, and 
12 mm. wide. 

Horizon and Locality: — This species is reported by Billings from 
division N, Table Head, Nfld. Professors Schuchert and Tvvenhofel 
collected one large cranidium from zone Mi, Table Head, and se\eral 
smaller ones from zones M2, Ni, N2, and the Isolated limestone, all 
at the same locality. It does not appear to be so common as A'. 
scrutator. I have seen it only from Newfoundland, and in the con- 
glomerate on lot 22, concession VI, two miles north of Mystic, Que. 

NiLEUS SCRUTATOR BilUngs. 
Plate 3, fig. 17. 
Nileus scrutator Billings, Pal. foss. Canada, 1865, 1, p. 274, fig. 260. 

This species is more common and is a larger species than the last. 
Although Billings figured only an imperfect cephalon, he described the 
p\'gidium and mentioned a couple of obscurely preserved complete 
specimens. That seven is the usual number of segments in the thorax 
is shown by the fact that this is the number present both in Billings's 
specimens and an entire one collected by Dr. R. INI. Field near 
Saltville, Xa. 

At the Thomas farm, near Blacksburg, Ya., where this species is 
fairly common, 1 found a single hypostoma. It is transversely oxal in 
outline, the gently convex body flanked by broad flat wings. The 
posterior border is slightly conca\-e, the cur\-ature interrupted l)y a 
short angular median projection. 

Measurements: — A large cranidium from zone X2, Table Head, 
Nfld., is 25 mm. long, and 35 mm. wide at the palpebral lobes. A 
pygidium from the same locality is 15 mm. long, and 31 mm. wide. A 
cranidium from Chatham Hill, \a., is 12.5 mm. long, and 19 mm. wide 
at the pHlpel)ral lobes. A pygidium from the same place is 8.5 mm. 
long, and Hi mm. wide. The entire specimen from near Salt\ille, V'a., 
is 35 mm. long; the cephalon 12 mm.; the thorax 10 mm.; and the 



RAYMOND: ORDOVICIAX TRILOBITE.S. 85 

pygidium 13 min. long. The hypostoma from near Blacksbiirg, Xa., 
is 6.5 mm. long, and 9.5 mm. wide. 

Horizon (lud Locality: — Billings recorded the species from division 
X at Table Head, and the conglomerates of P at Portland Creek, Nfld. 
Professors Schuchert and Twenhofel collected it in the following zones 
at Table Head, Xfld: — Leperditia bed, their locality 3,100—14, one 
specimen, zone Mi, one specimen, zone Ma, five specimens, zone N], 
one specimen, zone X'o, thirteen specimens. It is also found at Port 
au Port, specimens from this locality being present in the collections 
of both Yale and the M. C Z. 

It occurs in the Athens at the ciuarries east of Salt\ille, \a., at 
Chatham Hill, on the northern side of Walker Mountain, north of 
^Marion, Va., and in the middle and upper Athens at Bullsgap, Tenn. 
It is rather common at the top of the Holston at the Thomas farm, 
three miles northeast of Blacksburg, Va. Specimens have also been 
obtained from boulders in the conglomerate on lot 22, concession VI, 
two miles north of Mystic, Que. 

AsAPHiNAE Raymond. 
Basilicus laevici^lus, sp. nov. 

Plate 4, fig. 15, 16. Plate 6, fig. 15. 

Curiously enough Basilicus is very poorly represented in the south- 
ern Appalachians and I have seen so far only one fragmentary cranid- 
ium, one free cheek, one hypostoma, and one pygidium, all from 
Bland County, Va. Although there is no positive evidence that these 
are all fragments of one species, they will for the present be so regarded, 
since all occur at about the same horizon. 

The anterior end of the cranidium is broken away, but it was appar- 
ently short and wide. The glabella is not very definitely outlined, but 
is somewhat elevated and was evidently considerably higher than the 
border at the front. There are practically no traces of glabellar fur- 
rows, but faint lateral lobes can be made out back of the eyes. The 
neck-furrow is also nearly obsolete. The eyes are large, situated far 
back, and the palpebral lobes are flat. In front of the eyes the facial 
sutures turn abruptly outward and the glabella likewise expands. The 
free cheek is broad and shows a short flat genal spine. The hypostoma 
is large, rather smooth for this genus, with deep maculae and long 
pointed forks. 

The pygidium is short and smooth for the genus. It is gently con- 



SQ bulletin: museum of comparative zoology. 

vex, with a wide smooth axial lobe, and the pleural lobes show four 
pairs of short, faint, smoothly rounded ribs. The border is wide, 
rather steep, and gently concave. The ribs do not cross it, and al- 
though the axial lobe and the upper parts of the pleural lobes are 
practically smooth, the concave border is crossed by fine wavy cracks 
which follow a course nearly at right angles to the axis. 

Measurements: — The cranidium is too fragmentar\" to give an\' 
satisfactory measurements, but was probably about 55 mm. long, and 
60 mm. wide at the widest part in front of the e\'es. The hypostoma 
is about 37 mm. long, and 38 mm. wide. The pygidium is 61 mm. long, 
and 86 mm. wide. 

This species is not particularly like either Basilicus harrandi (Hall) 
or B. marginalis (Hall), the two American species of the genus, being 
much smoother than either, and the same remark applies to all the 
British forms except B. powisi (Murchison), a Caradoc form which 
seems closely allied. The cephala of B. laevicidus and B. potcisi agree 
in lacking glabellar furrows, in the abrupt outward turn of the sutures 
in front of the eyes, and in that the cheeks have very short spines. 
'The pygidia of the American form are smoother than the British ones 
ior they show no rings on the axial lobes and have only four instead of 
eight or nine pairs of obscure ribs. 

Horizon and Locality: — A rare species found so far only in the 
middle of the Holston in the McNutt quarry at Sharon Springs, in 
Bland Co., Va. The cranidium was collected by Dr. E. W. Shuler; 
the remainder of the specimens by the writer. Cotypes (M. C. Z. 
1,634-1,638). 

Homotelus Raymond. 

Bomotelus Raymond, Bull. M. C. Z., 1920, 64, p. 285. 
Onchometopus Raymond and Narraway, non Schmidt. 
Isotelus (partim) of authors. 

The generic name Onchometopus was first applied (Ann. Carnegie 
Tnus., 1910, 7, no. 1, p. 51; Raymond, Ibidem, p. 63) to an American 
trilobite b;\^ Raymond and Narraway in describing a new species from 
the Middle Ordovician of Minnesota and Pennsylvania. The essen- 
tial features of the trilobites for which this name has been used are 
the isoteliform glabella and sutures, but asaphiform lack of concave 
borders on the shields. Since my attention was first directed to this 
combination of characteristics, wider experience has shown that they 
form a large group in the Middle and Upper Ordovician and that 
although similar to the Russian Onchometopus they are probably not 



RAYMOND: ORDOVICIAN TRILOBITES. 87 

congeneric with it. The two genera form one more example of that 
paralleUsm among the Asaphidae to which 1 have already called 
attention (Proc. trans. Royal soc. Canada, 1912, ser. 3, 5, sect. 4, p. 
111). Detailed study with large numbers of specimens indicates that 
Onchometopus is a derivative of Asaphus, while Homotelus sprang 
from Isotelus, not once merely, but probably several times. Homo- 
telus differs from Isotelus chiefl\' in lacking the concave borders on the 
shields. Often specimens are found in which concave borders are 
feebly or sometimes even well developed, indicating that this char- 
acteristic is one of suppression and showing readily how a Homotelus 
could have been e\'olved time after time from various species of 
Isotelus. Homotelus cannot then be regarded in a strict sense as a 
good genus, but is a convenient term for a number of species showing 
similar characteristics. 

At the time of our first use of Onchometopus, Mr. Narraway and 1 
pointed out that the American species which we referred to the genus 
did not have the peculiar hooked doublure w^hich Schmidt considered 
the most important feature. In 1914 it was my privilege, aided by 
the Shaler Memorial fund, to collect Onchometopus from the typical 
localities south of Lake Ladoga, and direct comparison of specimens 
is now possible. Cephala of American and Russian forms are exceed- 
ingly alike in smoothness of glabella, position of eyes, course of facial 
sutures, and shape of fixed and free cheeks. Doublures are strikingly 
different not onl\- in the hooked and furrowed character of that of 
the Russian form, but also in its narrowness. Greater differences 
are seen in the thorax, where Onchometopus shows the high narrow 
ring of an Asaphus, while the Homotelus has the broader and flattened 
rings of the Isotelus. The pygidia again are similar, but that of 
Onchometopus is generally shorter and more nearly semicircular. 

As the type of Homotelus 1 selected a species from the Eden of the 
region of Cincinnati, chosen because of the excellent material available, 
and named it Homotelus ulrichi for Dr. E. O. Ulrich of the U. S. 
Geological Survey. 

Homotelus ulrichi Raymond. 
Plate 6, fig. 3-5. 
Homotelus ulrichi Raymond, Bull. M. C. Z., 1920, 64, p. 287. 

Outline of entire animal oval, whole surface rather evenly convex, 
the eyes being the only conspicuous prominences. C'ephalon and py- 
gidium about equal. 



88 bulletin: museum of comparative zoology. 

Cephalon twice as wide as long, nearly semicircular, but since the 
outline comes just within the semicircle, passing through the anterior 
point and genal angles, there is a suggestion of triangularity. The 
glabella is smooth, not differentiated. On an occasional specimen 
there are two pairs of pits between the eyes, the vestiges of two pairs 
of glabellar furrows. The neck-furrow is practically obsolete and just 
in front of its normal position is a \'ery small median pustule. The 
dorsal furrows are very faint except on crushed specimens. The eyes 
are small, strongly elevated and far apart. The palpebral lobes are 
small, conca^'e on top and so short that a part of the visual surface 
looks upward. The genal angles are rounded and the sides of the 
cheeks have a narrow flattened and striated border which stands at an 
angle with the general surface and is turned downward at the sides and 
front. This joins the nearly horizontal doublure in a sharp edge. 

Axial lobe of thorax wide, but less than one half the entire width. 

Pygidium not quite twice as wide as long, the narrow axial lobe 
faintly but definitely outlined, most prominent at the posterior end. 
Pleural lobes smooth. 

Measurements: — The entire specimen selected as the type is 58 mm. 
long, and 33 mm. wide at the genal angles. The cephalon is 18.5 mm. 
long; the eye 5 mm. long, and the back of the eye 6 mm. from the pos- 
terior margin of the head. The thorax is 20 mm. long, 32 mm. wide 
at front, and 32 mm. wide at back. The axial lobe is 15 mm. wide at 
front, and 13.5 mm. wide at back. The pygidium is 19.5 mm. long, 
32 mm. wide at the front. The axial lobe is 15 mm. long. 

Homotelns obtnsus (Hall) of the Chazy differs from this species in 
having more strongl;s' impressed furrows and particularly in its very 
conspicuously punctate shell. Homotehts simplex (Narraway and 
Raymond) is much more closely like the present one but has the eyes 
larger and farther back, more traces of ribs on the pygidium, and lacks 
the angulated border on the cephalon. 

Horizon and Locality: — This species seems to be quite common in 
the Eden in the vicinitA- of Cincinnati, Ohio, but as the specimens are 
all in the Dyer collection 1 have no data on either exact horizon or 
locality. Cotypes (M. C. Z. 1,575, 1,576). 

Homotelus elongatus Raymond. 

Plate 4, fig. 1-3. 

Homotelus elongatus Raymond, Bull. M. C. Z., 1920, 64, p. 288. 
Onchometopus simplex Bassler {non Raymond and Narraway), Maryland geol. 
surv. Cambrian and Ordovician, 1919, p. 348, pi. 47, fig. 11. 



RAYMOND: ORDOVICIAN TRILOBITES. 89 

Test large for the genus, elongate, both shields subtriangular, 
strongly convex. Cephalon subtriangular, less than twice as wide as 
long, evenly convex. Glabella smooth, not outlined, dorsal furrows 
present only back of the eyes and glabellar furrows obsolete. P^yes 
prominent, situated a little back of the middle but more than their 
length ahead of the posterior margin. Genal angles rounded. 

Thorax abruptly deflected at the sides, depressed convex on top. 
Axial lobe less than one half the total width. 

Pygidium triangular, strongly and evenly convex, the axial lobe 
hardly outlined except at the posterior end. Exfoliated specimens 
show traces of several ribs on the pleural lobes. 

Measurements: — One entire, but much damaged, specimen is about 
105 mm. long and 60 mm. wide at the genal angles. A well-preserved 
pygidium is 44 mm. long, and 63 mm. wide. A smaller one is 36 mm. 
long, and 51 mm. wide. 

This species is readily recognized by its highly convex triangular 
shields. The axial lobe of the pygidiinn is also less strongly defined 
than in most other species. 

Horizon and Locality: — A very common species in the lower 
Echinosphaerites zone of the Chambersburg in the vicinity of Cham- 
bersburg and jNIarion, Pa. and Strasburg, Va. Bassler reports it from 
the Nidulites zone of the Chambersburg at Wilson, Md. Cotypes 
(M. C. Z. 1,577-1,579). 

HoMOTELUS INDENTUS Raymond. 
Plate 4, fig. 6. Plate 5, fig. 7. Plate 9, fig. 2. 
Homotelus indentus Raymond, Bull. M. C. Z., 1920, 64, p. 288. 

This species is so far represented only by pvgidia, but these differ 
obviously from the majority of species of the genus in their more 
elongate form and the upturned posterior border. The axial lobe is 
long, narrow^ gentl\- tapering, and prominent. The pleural lobes 
ribless, evenly convex. Back of the axial lobe the posterior margin 
is upturned, so that in this region there is a concave border. This 
upward tilt in the posterior margin suggests a somewhat pointed 
cephalon. The surface of the test is covered with small flat-bottomed 
circular depressions which are arranged about as closely together 
as they can be and still retain their circular shape. They appear to 
be very large, but superficial puncta. Along the borders these are 
less numerous, and among them are numbers of short wavy cracks 



90 bulletin: museum of comparative zoology. 

roughly parallel to the margin. Exfoliated specimens, of course, show 
no trace of this ornamentation, but do show faint traces of ribs on the 
pleural lobes. 

Measurements: — The largest pygidium is 43 mm. long, and 57 mm. 
wide. The axial lobe is 35 mm. long, and 17 mm. wide at the front. A 
second specimen is 33 mm. long, and 45 mm. wide. The ratio of length 
to width indicates the elongation of the pygidium in this species. This 
index in H. vlrichi, which is more like H. indentiis than anv other de- 
scribed species, is about 610, in H. ohiusus it is 655-680, in H. elongatus, 
which has a long pygidium, it is about 700, whereas in the largest speci- 
men of H. indentxis it is 754. 

Aside from the length of the pygidium and the upturned posterior 
margin, the character of the ornamentation serves to identify this 
species. 

Horizon and Locality: — This seems to be a rather rare species, 
found so far only in the Holston in the Catawba Valley, north of 
Salem, and on the Hoge farm, nine miles southwest of Bland, Va. The 
specimens from this latter locality were collected by Dr. E. W. Shuler. 
Cotypes (M. C. Z. 1,580, 1,581).' 

HOMOTELUS OBTUSUS (Hall), 
Plate 4, fig. 7, 8. 

Asaphus ? obtusus Hall, Pal. N. Y., 1847, 1, p. 24, pi. 4 (bis), fig. 14. 
Onchometopus obtusus Raymond, 7th rept. Vermont state geol., 1910, p. 22, pi. 
34, fig. 1, 2, pi. 38, fig. 2-4. Bassler, Bull. 92, U. S. N. M., 1915, p. 8*73. 

This species, or one exceedingly closely allied to it, is very abundant 
at the top of the Holston at the Thomas farm, three miles northeast of 
Blacksburg, Va. All the specimens are dissociated pieces: — cranidia, 
free cheeks, hypostomata, thoracic segments, and pygidia. The 
specimens agree with H. obtusus in having the eyes farther back than 
in other species of the genus, in the short, rounded form of the pygid- 
ium, the faintness of the axial lobe on the abdominal shield, and more 
particularly in the presence of numerous large puncta on the test. 
The puncta are not, however, as prominent as in the typical speci- 
mens. 

Measuremenis: — A cranidium 17 mm. long indicates that the eye 
was 5 mm. long and the posterior margin of it 3.5 mm. from the poste- 
rior edge of the cephalon. A large pygidium is 21 mm. long, and 32 mm. 
wide. A pygidium of H. obtusus from Valcour Island, N. Y., is 17 mm. 



RAYMOND: ORDOVICIAN TRILOBITES. 91 

long, and 25 mm. wide. The ratio of length to width is very nearly the 
same, the index being 656 in one case and 680 in the other. 

Horizon and Locality: — In the t^\'pieal region in Vermont and New 
York, Homotelus obhistis is most common in the upper part of the 
Chazy. In Virginia it is very abundant in the top of the Holston on 
the Thomas farm, three miles northeast of Blacksburg, and occurs also 
in the upper part of the Holston in the Catawba Valley, north of Salem, 
and at the base of the Liberty Hall at Lexington, Va. 



Homotelus laevis Raymond. 
Plate 9, fig. 3, 4. 
Homotelus laevis Raymond, Bull. M, C. Z., 1920, 64, p. 289. 

This name is suggested for a species, the pygidia of which are com- 
mon and of which a few fragmentar\' cranidia and free cheeks have 
been seen. In general outline and proportions the pygidium is most 
like that of H. obtusus, but the axial lobe is more strongly developed 
and the puncta are much fewer, finer, and farther apart. There is 
also a faint concave border on the posterior part. The cranidium 
is very slightly convex, the eyes large and well back. The cephalon 
is in fact much more typically isoteliform than that of an\- other 
species. Exfoliated or compressed specimens show rather plainly the 
ribs of the pygidium. 

Measurements: — A small pygidium is 22 mm. long, and about 
35 mm. wide. The axial lobe is 16 mm. long, and 11 mm. wide at the 
front. A large specimen (flattened) is 45 mm. long, and about 70 mm. 
wide. 

Horizon and Locality: — This species is exceedingl\' common in the 
Athens at Chatham Hill, on the northern slope of Walker Mountain, 
north of Marion, Va. It is also found in the same formation near 
White Gate and Tilsons Gap, Bland Co., and in the Holston near 
McDonalds Mills in the Catawba Valley, north of Salem, Va., in all of 
which localities it was collected by Dr. E. W. Shuler; and also in the 
Holston at the McNutt quarry, Sharon Springs, ^^a. A single large 
pygidium collected by the writer in the Athens near Saltville, Va., is 
probably of this same species. In the lower part of the Athens near 
Bullsgap, Tenn., the species is quite common. Holotype (M. C. Z. 
1,600); paratype (M. C. Z. 1,607). 



92 bulletin: museum of comparative zoology. 

HoMOTELUS LAEVIURUS Raymond. 
Plate 4, fig. 4, 5. 
Homotelus laeviurus Raymond, Bull. M. C. Z., 1920, 64, p. 290. 

This species has a short broad cranidium, of little con\'exity, on 
which the glabella is entirely merged into the general surface, and 
dorsal and glabellar furrows quite absent. The median pustule is 
small, but prominent on the otherwise smooth surface, and the shell 
seems devoid of puncta. The free cheeks and thorax are unknown. 

The pygidium is evenly convex and the only marking is a very 
slight swelling indicating the position of the posterior end of the axial 
lobe. Even in internal casts the outline of the axial lobe shows only 
vaguely. 

Measurements: — A cranidium is 17 mm. long, and 24 mm. wide at 
the tips of the fixed cheeks. At the widest point in front of the eyes 
it is 16 mm. wide. Another cranidium is 11.5 mm. long, 16 mm. wide 
at the tips of the fixed cheeks, and 9.5 mm. wide at the palpebral lobes. 
A pygidium is 14 mm. long, and 19 mm. wide. 

This species is more nearly allied to Homotelus simplex Raymond 
and Narraway than to any other described species, but has smoother 
shields, and the pygidium in particular shows less trace of the axial 
lobe. The absence of puncta in the shell separate it from H. obtusus, 
the only other species with which it could be confused. 

Horizon and Locality: — A \er\- common trilobite in the Kimms- 
wick limestone at Mincke, Mo., where it was collected by Dr. D. C. 
Barton. Cotypes (M. C. Z. 1,584, 1,585). 

Homotelus catactus Raymond. 
^ Plate 5, fig. 5. 

Homotelm catactus Raymond, Bull. M. C. Z., 1920, 64, p. 290. 

The only representative of this genus so far found on Newfoundland 
is a single cranidium which does not seem referable to any of the 
described species. 

This specimen indicates a short and wide cephalon which was evenly 
arched and rather convex for the genus. The glabella is merged com- 
pletely into the general surface, and both dorsal and glabellar furrows 
are completely absent. The facial sutures turn far outward in front 
of the eyes, so that this portion of the cranidium is wider than in any 



RAYMOND: ORDOVKIAN TRILOBITES. 93 

Other species of the genus. The palpebral lobes are large, indicating 
very large eyes, and are situated a little more than their own length 
in front of the posterior margin, but not quite twice their length from 
the anterior edge. The surface, so far as can be determined from a 
largely exfoliated specimen, is smooth. 

This species differs from any previously described in ha\ing larger 
eyes and in the greater width of the portion of the cranidium in front 
of them. 

Measurements: — Length of cranidium, about 32 mm., width at pal- 
pebral lobes 32 mm. Length of palpebral lobe 8 mm., distance from 
back of palpebral lobe to posterior margin 11 mm. 

Horizon and Locality: — The single specimen was collected by Pro- 
fessor Dunbar from a pel)ble in the Cow Head conglomerate on Stear- 
ing Island, Xfld, and is in the Yale University IVIuseum. 



HoMOTELUS susAE (Whitfield). 

Asa-phiis susae Whitfield, Geol. Wi.sc., 1882, 4, p. 236, pi. 5, fig. 3, pi. 10, fig. 8. 

Chamberlin, Geol. Wise, 1883, 1, p. 160, fig. 
Asaphus (Isotelm) sii^ae Calvin, Iowa geol. surv., 1903, 13, p. 46. 
Not Asaphus, Isotelus, Onchometopus susae of Whiteaves, Clarke, and Raymond. 

Calvin has pointed out the distinction between the original Asaphus 
susae of the Trenton and the rather similar Isotelus sitsae of the IVIaquo- 
keta. He says of the former that " It is smaller, more convex, thicker 
in front than posteriorly, with the anterior part of the head deflected 
so that near the front margin the surface of the glabella stands nearly 
at right angles to the general plane of the body — characteristics 
correctly shown in Whitfield's Figure 8, Plate 10. The eyes are more 
prominent, the visual surface is larger than in the species figured and 
described by Clarke, and the posterior limb of the glabella is much 
narrower in proportion to its length." Calvin was able to compare 
specimens from the upper part of the Trenton near Florenceville, 
Howard Co., Iowa, with specimens from the Maquoketa of the same 
region, so his opinion is gi\en especial weight. He found that the 
examples from the higher l)eds agreed with those described by Clarke 
as Isotelus snsae, and for this latter species suggested the name Isotelus 
flo renceinllen s is. 

Horizon and Locality: — Homotelus susae, as restricted, is known only 
from the upper Trenton at Apple River, Jo Daviess Co., 111., and at 
the same horizon near Florenceville, Howard Co., Iowa. 



94 



BrLLETIN: MrSELM OF COMPARATIVE ZOOLOGY. 



HOMOTELUS FLORENCEVILLENSIS (Calvin). 

Isotelus susae Clarke, Geol. Minn., 1897, 3, pt. 2, p. 708, fig. 10, 11. 
Isotelusflorencevillensis Calvin, Iowa geol. surv., 1903, 13, p. 46. 

Calvin's reasons for flistinguishing this species from Homotelus susae 
have been set forth under the preceding caption. Summarized, it 
may be said that //. florniccvillcnsis has a broader and more depressed 
form, less prominent eyes, a longer and flatter glabella, a longer 
pygidium, and a less definitely outlined axial lobe on the latter shield 
than H. susoc. The species are, however, much alike, and without 
direct comparison of specimens a separation would probably not have 
been made. 

Horizon and Localiiii:— This species is so far fully identified only 
in the Maquoketa at Granger and Spring Valley, Minn., and the 
vicinity of Florence ville, Howard Co., Iowa. 



HoMOTELUs GRATiosus Raymond. 

Plate 6, fig. 1, 2. 

Homotelus gratiosm Raymond, Bull. M. C. Z., 1920, 64, p. 291. 

Asaphus (Isotelus) smae Whiteaves (no?i Whitfield), Pal. foss. Canada, 1897, 

3, pt. 3, p. 231. 
Onchovietopus susae Raymond, Proc. and trans. Roy. soc. Canada, 1912, 

ser. 3, 6, sect. 4, pi. 2, fig. 1, 2. 

Cephalon nearly semicircular, evenly convex, with large, elevated 
eyes. Cranidium absent from the type, but on other specimens de- 
pressed, smooth, glabella not outlined. Fixed cheeks smooth, genal 
angles rounded. Eyes large, near the middle of the cephalon. 

The axial lobe of the thorax is wide for an Homotelus, being nearly 
one half the total width. 

Pygidium short and wide, nearly semicircular, with the axial lobe 
outlined at the anterior end only. 

Measurements: — Length of cephalon 25 mm., width 51 mm.; the 
eye is 10 mm. long. Total width of thorax at middle 48 mm.; width 
of axial lobe 23 mm. Length of pygidium 26 mm., width 46 mm. 

This species differs from Homoiclus florenceriUensis, which occurs at 
the same horizon, in having the eyes much farther forward and larger, 
as well as in the shorter and wider shields. It differs from other 
known species of the genus in the same particulars. 



RAYMOND: ORDOVICIAM TRILOBITES. 95 

Horizon and Locality: — The holotype, a gift of Mr. A. H. Becker 
and Mr. John H. Bradley, Jr., (M. C. Z. 1,5^), was found near the 
top of the Maquoketa at Patterson's Spring, near Brainerd, Iowa. 

VoGDESLA. Raymond. 

Although proposed as a subgenus of Nileus, Vogdesia proves to be 
one of the Asaphinae, and closely related to Homotelus and Braehyas- 
pis. This conclusion has been reached from a study of the dorsal 
surface, as the hypostoma has not yet been seen. Vogdesia differs 
from both the genera mentioned in having a wider axial lobe in the 
thora.x, and little or no trace of dorsal furrows on the pygidium. The 
type is Vogdesia bearsi Raymond, from the Chazy. Other species 
are Vogdesia nmmesoiensis (Foerste) and Nileus sp. (Foerste, Bull. 
Denison univ., 1920, 19, p. 218, pi. 23, fig. 4A, B), both from the 
Trenton, and Vogdesia rigilans (Meek and Worthen), a common 
trilobite in the Maquoketa. 

Vogdesia gigas Raymond. 
Plate 6, fig. 8. 
Vogdesia gigas Raymond, Bull. M. C. Z., 1920, 64, p. 292. 

This species differs from T. vigilans only in that the type is twice 
as large as the largest known specimen of the latter, the eyes are 
farther from the anterior margin, and the test is slightly if at all punc- 
tate. 

Measuremenis:— Specimen, if extended, about 120 mm. long. The 
cephalon is 34 mm. long, and 58 mm. wide; an eye is 8 mm. long, and 
8 mm. from the posterior margin. The pygidium is 36 mm. long, and 
55 mm. wide, with no trace of an axial lobe. The thorax is estimated 
to be about 50 mm. long, each of the eight segments being 7 mm. long 
in the enrolled state. 

Horizon and Locality: — This species is known from a single speci- 
men collected by the writer near the base of the Maquoketa on a 
creek four miles west of Clermont, Iowa. Holotype (M. C. Z. 1,589). 

Vogdesia vigilans (Meek and Worthen). 

Asaphiis {Isoteliis) vigilans Meek and Worthen, Proc. Acad. nat. sci. Phil., 
1870, p. 53. Geol. surv. 111., 1875, 6, p. 497, pi. 23, fig. 6. 



96 bulletin: museum of comparative zoology. 

Nileus vigilans Finch, Proc. Iowa acad. sci., 1904, 11, p. 179, pi. 14. Slocom, 
Bull. Field mus. nat, hist. Geol. ser., 1913, 4, no. 3, p. 52, pi. 14, fig. 9-15. 
Ann. rept. Geol. surv. Iowa, 1916, 25, p. 199, pi. 15, fig. 9-15. 

Vogdesia vigilans Raymond, Ann. Carnegie mus., 1910, 7, p. 70. 

Not Nileus vigilans of Clarke, Schuchert, and Grabau and Shimer. 

This species is too well known to need an;s- comment, and I am list- 
ing it here to emphasize the generic reference and to correct the bibli- 
ography. 

Slocom says, "Free cheeks finely punctate." The same is true of 
the remainder of the body. 

Horizon and Locality: — The original specimens were from the upper 
Ordovician shales of Carroll and Kendall Counties, 111. It is very 
common in the lower Maquoketa near Elgin and Clermont, Iowa. It 
is also reported by Slocom from the same horizon at Bloomfield and 
from the upper Maquoketa at Patterson's Springs near Brainerd, Iowa. 

Vogdesia minnesotensis (Foerste). 

Illaenus {Nileus) minnesotensis Foerste, 15th rept. Geol. nat. hist. surv. Minn.. 

1886, p. 478, fig. 1. 
Nileus vigilans Clarke, Geol. Minn., 1897, 3, pt. 2, p. 712, fig. 17-19. Schu- 

chert, Proc. U. S. N. M., 1900, 22, p. 173. Grabau and Shimer, N. A. 

index foss., 1910, 2, p. 299, fig. 1610 c, d. Slocom, Bull. Field mus. nat. 

hist. Geol. ser., 1913, 4, no. 3, p. 53. Ann. rept. Geol. surv. Iowa, 1916, 

25, p. 200. 

Slocom has pointed out that the specimens of Nileus vigilans 
found in the Trenton differ from the typical specimens in having the 
facial sutures marginal in front of the cranidium and in having the 
anterior part of the cephalon much less inflated. To this should be 
added the fact that the eyes are much less elevated and the palpebral 
lobes much larger, so that they cover a greater portion of the top of 
the eyes. 

The lower e^tcs and depressed cranidium gi\e this form quite a 
different appearance from the true F. vigilans, and since it has already 
recei\ed a name, it may as well be recognized as a distinct species. 

Horizon and Locality: — This species is reported by Clarke from 
the Lower Trenton at Minneapolis and the "Galena" at Wykoff' and 
Pleasant Gro\'e, Minn. Foerste's original specimen was from Minne- 
apolis. Specimens collected by the writer at Owatonna, Minn., are 
in the Carnegie Museum. Schuchert reported it from the Trenton of 
Baffin Land. 



RAYMOND: ORDOVICIAN TKILOBITES. 97 

NiLEOiDES Ra\THond. 
Nileoides Raymond, Bull. M. C. Z., 1920, 64, p. 284. 

Some years ago 1 described a Chazyan triloiiite under the name 
Nileus i)crkinsi. Although similar to Nileus, this species differs from 
all others of that genus in having the eyes relatively small and par- 
ticularly in ha\ing them very far back. Another peculiarity is the 
strong de\'elopment of the \ertical suture on the doubhu'e. I have 
examined with care great numbers of specimens of Nileus from Norway 
and Sweden without ever finding this suture, nor does it show in any 
of the xA-merican specimens. The strong development on Nileoides 
perkinsi is therefore of considerable importance. 

Cephalon Nileus-like, glabella not outlined, cranidium smooth, 
gently convex, elongate, not abruptly inflected in front of the eyes. 
Eyes large, but not so large in proportion to the length of the cephalon 
as in Nileus. Vertical suture present. Axial lobe of thorax wide. 

Type: — NileKS perkinsi Raymond. Upper Chazy, Vermont, and 
New York. 

Nileoides perkinsi Ra^^nond. 

Nileus perkinsi Raymond, Ann. Carnegie mus., 1910, 7, p. 69, pi. 18, fig. 7, 8. 

7th rept. Vermont state geol., 1910, p. 224, pi. 38, fig. 7, 8. Proc. and trans. 

Roy. soc. Canada, 1912, ser. 3, 5, sect. 4, p. 119, pi. 2, fig. 8, pi. 3, fig. 1. 
Nileoides perkinsi Raymond, Bull. M. C. Z., 1920, 64, p. 284. 

This rare species has previously been known from only two speci- 
mens, one a cephalon, the other a cephalon and five segments of the 
thorax. Both were found on Isle La Motte, Vt. In 1919 1 obtained 
a specimen in the reef at the base of the Upper Chazy, east of Chazy, 
N.Y., which retains the cephalon, thorax, and the anterior part of 
the pygidium. The vertical suture of the doublure is well shown, 
thus confirming the evidence of the other specimens. 

The thorax contains eight segments, which are wide, flat, smooth, 
and lack dorsal furrows. There is not enough of the pygidiiun pre- 
served to give am' idea of its characteristics. 

ISOTELUS lOWENSIS Owcn. 

Asaphus (Isotelus) ioivensis Owen, Rept. Geol. surv. Wise, Iowa, ]Minn., 1852, 
p. 577, pi. 2, fig. 3-7, pi. 2, fig. 1-8. 

Isotelus iowensis Clarke, Geol. Minn., 1897, 3, pt. 2, p. 704. Slocom, Bull. 
Field mus. nat. hist. Geol. ser., 1913, 4, no. 3, p. 48, pi. 13, fig. 1, 2. Ray- 
mond, Bull. M. C. Z., 1914, 58, p. 255, pi. 2, fig. 6 (71071 pi. 3, fig. 1, 2). 
Slocom, Ann. rept. Geol. surv. Iowa, 1916, 25, p. 193, pi. 14, fig. 1, 2. 



98 bulletin: museum of comparative zoology. 

Isotelus maximus Clarke {■partim), Geol. Minn., 1897, 3, pt. 2, p. 703, fig. 5. 
Isotelus gigas Weller, Geol. surv. New Jersey Pal., 1903, 3, pi. 14, fig. 5. 

After making a considerable collection of Isotelu.s in the vicinity of 
Clermont and Elgin, Iowa, I conclude that there are two species there 
which have been passing under the name Isotelus iowerisis. One form 
has a very punctate surface and the pygidium shows only faint traces 
of ribs. The other has very few puncta in the test, and the ribs are 
rather conspicuous on the surface, especially two or three at the 
anterior end of the pygidium. The second form also has a more 
elongate, less rounded pygidium than the first. Mature specimens 
are distinguished without difficulty, but exfoliated examples of the 
young are too much alike to be differentiated. 

That the smoother of these forms is the original /. iowensis is shown 
by reference to Owen's original description and his metal-ruled figures 
on his plate 2 A. The restored view of plate 2, figure 3, is so obviously 
incorrect in many particulars that it cannot be taken as an illustration 
of the species. 

Slocom has recently given a full description of this species, so that 
1 shall refer only to a couple of details. Both Owen and Slocom state 
that the anterior margin of the cranidium makes a smooth cur\e, and 
that the sutures do not meet at an angle. This observation must have 
been based on poorly exposed material, for good specimens of free 
cheeks, cranidia, and entire cephala show that the sutures do meet at 
an angle, and that the free cheeks, though narrow, do extend to the 
middle of the front of the cephalon. 

Horizon and Localiti/: — This species is very common in the Maquo- 
keta shales at Elgin and in the \icinity of Clermont, Iowa, anfl Clarke 
figured a specimen from the same formation at Granger, Minn. 



Isotelus walcotti Walcott. 

Isotelus walcotti Walcott (Ulrich Mss.), Smith, misc. coll., 1918, 67, p. 190, pi. 

24, fig. 1. 
Isotelus iowensis Raymond (partim), Bull. M. C. Z., 1914, 58, p. 255, pi. 3, 

fig. 1, 2 {nan pi. 2, fig. 6). 

In discussing the specimens from the Trenton at Trenton Falls, 
N. Y., which in 1914 I referred to Isotelus iowensis, 1 stated that "The 
specimens from the Trenton, though sometimes larger, are too much 
like the Iowa specimens to be distinguished as a distinct species at the 
present time." 



RAYMOND: ORDOVICIAN TRILOBITES. 99 

Wak'ott has recently figured, without description, one of these 
specimens from Trenton Falls, and given to it a manuscript name sug- 
gested by Dr. Ulrich. After restudying the material from the Trenton 
in connection with a much larger collection from the Maquoketa than 
was a\ailal)le to me five years ago, 1 am al)le to find some minor 
dift'erences which may justify the new species, especially since the 
specimens are found in such widely separated localities and at difTerent 
horizons. The chief difference lies in the fact that although the 
glabellae of the two forms are alike in shape and furrows, the anterior 
portion is much more definitel.\' outlined in /. walcotii than in /. ioivoi- 
sis, and there is also a median carina along the middle of the glabella 
in the former species, as shown in Dr. Walcott's figure. 

The change in name does not alter the force of my remarks in the 
paper of 1914. Isoielus walcoffi was apparently derived from /. gigas 
through the inhibition of complete development and grew to adult size 
while retaining many of the juvenile characteristics. Isofiius lownisis 
is a \ery slightly modified descendant which survived to the late 
(}rdo\ician. This furnishes a very good example of the formation of a 
new species by a sudden "jump," due in this case to the failure of com- 
plete de^•elopment (brady genesis). 

Horizon and Locality: — All of the completely identified specimens 
of Isoielus walcoffi have been found in the "Walcott quarry," east of 
the gorge at Trenton Falls, N. Y. There are eight complete specimens 
and a number of fragmentary ones in the M. ('. Z. 

LsoTELUS REJUVENis Raymond. 
Plate 5, fig. 6. 
Isoielus rejuvenis Raymond, Bull. M. C. Z., 1920, 64, p. 294. 

Entire specimen elongate o\al, narrow, strongly convex. Cephalon 
large, with short genal spines which in uncrushefl specimens have their 
outer surfaces nearly vertical. The facial sutures follow the same 
course as in /. iowcnsis, being very close to, and parallel to the anterior 
margin. The eyes are very small, elevated, situated a trifle more than 
their own length in front of the posterior margin. The glabella is 
faintly outlined, constricted between the eyes, and nearly smooth. 

Thorax as in /. ioicensis, the dorsal furrows shallow, and the axial 
lobe more than one third and less than one half the total width. 

Pygidium elongate, narrow, with steep sides. The axial lol)e is 
narrow, faintly outlined except in young specimens, and without rings 



100 



bulletin: museum of comparative zoology. 



except for the one on the anterior end. The pleural lobes show traces 
of several pairs of ribs, two of which at the anterior end are very 
distinct. 

Measurements: — The holotype is 105 mm. long; the cephalon is 
38 mm. long, and 62 mm. wide; the pygidium is 46 mm. long, and 
55 mm. wide. 

This species differs from Isotelns iowensis in ha^•ing smaller eyes, a 
longer and narrower pygidiuna with two pairs of ribs on the anterior 
end, and in having a less densely punctate shell. 

In the following table, measurements (in mm.) of specimens of 
Isotelus rejuvenis, I. oicensis, and /. walcotti are gi\'en in parallel col- 
umns for comparison. It will be noted that although the proportions 
of specimens of /. walcotti and /. iowensis are about the same, /. 
rejuvenis is somewhat narrower, and has a longer p\gidium. 





Isotelus 
rejuvenis 


Isolelus 
iowensis 


Isotelus 
uatcotti 


Total length 


105 




52 






54 




Greatest width 


62 




30 






31 




Index — Width -=- length 


.59 




.57 






.57 




Length cephalon 


38 




19 






19 




Ilndex- — Length -^ width 


.61 




.63 






.61 




Length pygidium 


46 


37 


19 


60 


40 


20 


49 


"Width pygidium 


55 


42 


25 


77 


54 


26 


64 


Index — Length -^ width 


.87 


.88 


.76 


.78 


.74 


.77 


.76 



Horizon and Locality: — The species has so far been found only in 
the lower part of the Maquoketa at Clermont and Elgin, Iowa, at both 
of which places it is rather common in association with /. iowensis. 
The holotype (M. C. Z. 1,586) was' collected by the writer on a creek 
about four miles west of Clermont. 



RAYMOND: ORDOVICIAN TRILOBITESi. 101 

EcTENASPis Raymond. 
Edenaspis Raymond, Bull. M. C. Z., 1920, 64, p. 292. 

Several years ago Mr. A. G. Becker, while collecting in the ravine 
of a small stream about two miles west of Clermont, Iowa, came upon 
a slab of limestone on which were two specimens of the trilobite which 
Slocom later described as McgaJaspis bcckcri (Bull. Field mus. nat. hist. 
Geol. ser., 1913, 4, p. 50, pi. 14, fig. 5. See also Geol. surv. Iowa, 1916, 
25, p. 196, pi. 15, fig. 5). The outstanding feature of this animal is the 
great elongation of the anterior portion of the cephalon. The elongate 
triangular head-shield invited a comparison with such asaphids as 
Megalaspis extcniiata (Dahnan), hence the generic reference. 

Xo one has as yet been fortunate enough to disco^■er an hypostoma 
of this species, so that it is not possible to sa^• definitely that M. 
beckeri is not a Megalaspis, but that it is almost certainly not one is 
indicated by the following considerations : — 

1st. Nearly all the species of Megalaspis in the typical region in 
northern Europe are found in the Lower Ordovician, only one or two 
surviving till the ^Middle Ordovician, and none till the Upper Ordovi- 
cian rocks were deposited. 

2d. Megalaspis is exceedingly rare in America, whereas isotelids are 
common and highl^• ^'ariable. 

3d. Xo hypostoma of the ogygiocarinid type has been found in 
the Maquoketa. 

4th. The glabella of Megalaspis beckeri is not definitely outlined 
and is long, whereas in all species of the true Megalaspis the glabella is 
outlined and is relatively short. 

5th. The axial lobe of the thorax of M. beckeri is wider in propor- 
tion to the total width than is that of any species of the true Mega- 
laspis. 

In consideration of the above, I made Megalaspis beckeri the type of 
a new genus, Ectenaspis, the extended or stretched out character 
of the cephalic shield suggesting the name. This genus seems very 
close to Isotelus, and its derivation from Isoteloides through some 
such forms as /. angusticaiuJus Raymond and Ectenaspis homalono- 
toides (Walcott) is quite probable. 

Ectenaspis beckeri (Plate 9, fig. 7) is an exceedingly rare fossil in the 
lower part of the Maquoketa (Upper Ordovician) in Fayette Co., Iowa. 
The only other species which can now be placed in this genus is Ecten- 
aspis homalonotoiclcs (Walcott). 



102 bulletin: museum of comparative zoology. 

ECTENASPLS HOMALONOTOIDES (Walcott). 

Plate 4, fig. 9, 10. 

Asaphus homalonotoides Walcott, 31st rept. N. Y. state mus. nat. hist., 1879, 

p. 70 (advance sheets, 1877, p. 70). Whitfield, Geol. Wise, 1882, 4, p. 

237, pi. 5, fig. 4. 
Asa-phus iriangulafus Whitfield, Ann. rept. Wise. geol. surv., 1879 (1880), 

p. 59. 
Isoieloides homalonotoides Raymond, Bull. 1, Victoria mem. mus., 1913, pi. 4 

fig. 5. 
Not Isoteloidoi homalonotoides Raymond and Narraway, Ann. Carnegie mus., 

1910, 7, p. 52, pi. 16, fig. 9-11. 

Lack of figures has caused some confusion about tliis species, both 
to Whitfield and myself. The types are in the Walker Museum at the 
l'ni\ersity of Chicago, and Mr. A. W. Slocom was good enough to send 
me excellent casts from which I have had illustrations prepared. The 
anterior end of the cranidium is drawn out into a sharp point in the 
same manner though not to so great an extent as that of Kdcuaspis 
beckeri, and the pygidia of the two species are practicall\- identical. 
It seems therefore that Asaphtis homalonotoides must be referred to 
Ectenaspis rather than to Isoteloides. 

The cranidium is long and narrow, pointed in front, depressed con- 
vex. The glabella is definitely, though faintly, outlined, about three 
fourths the total length, has nearly parallel sides, Ijeing contracted but 
slightly lietween the eyes, and shows faintly two pairs of glabellar 
furrows. The eyes and palpebral lobes are entirely broken away, but a 
fold in the test just in front of them indicates that they were ele\ated, 
possilily high, as in E. beckeri. They are situated fiir back and the 
fixed cheeks are very narrow. The neck-furrow is shallow on the 
axial lobe, somewhat more distinct on the fixed cheeks. In front of 
the glabella is a wide depressed border. 

The p^•gidium is triangular, pointed behind, with a narrow concave 
border. The axial lobe is prominent, narrow, eight tenths the entire 
length. There are traces of about six rings on the axial lobe, and 
three or four pairs of ribs show faintly on the sides. 

Measurements: — The cranidium is 16.5 mm. long, 11 mm. wide in 
front of the eyes; and the glal)ella is 12 mm. long. The p\gidium is 
18.5 mm. long, 23 mm. wide at the front; the axial lobe is 15 mm. long, 
8 mm. wide at the front, and 3 mm. wide 2 mm. in front of the posterior 
end. 

The only known specimen showing the thorax is that in the Victoria 



RAYMOND: ORDOVICIAN TRILOBITES. 



103 



Memorial Museum at Ottawa. It retains seven segments attached 
to the pygidium, and shows that the axial lobe occupies about the 
same proportion of the total width as in E. bcckeri. 

Horizon and Locality: — The types were found at Dunlith, 111., at 
a horizon said to be near the base of the Trenton. The specimen in 
Ottawa was found by Mr. W. A. Johnston in the crinoid beds along the 
Trent Canal near Kirkfield, Ont., at a horizon less than eighty feet 
above the base of the Trenton. 

Hyboaspis Raymond. 
Hyboaspis Raymond, Bull. M. C. Z., 1920, 64, p. 385. 

This name was proposed for a curious trilobite in the pygidium of 
which are combined the elongate form of the asaphid and the short 
axial lobe of the illaenid. 1 know of no asaphid with short axial lobe 
on the pygidium and only in Actinolobus among the lllaenidae is 
there any hint of elongation of the pygidium and even there nothing 
comparable to what is seen in the form described. Although the 
ascription of the genus to either the Asaphidae or lllaenidae cannot 
positively be made until the cephalon is found, 1 have for the present 
placed it with the Asaphidae. Type:— Hyboaspis shuleri Raymond. 

Hyboaspis shuleri Raymond. 
Plate 5, fig. 3, 4, 8. 
Hyboaspis shuleri Raymond, Bull. M. C. Z., 1920, 64, p. 285. 

Cephalon and thorax unknown. 

Pygidium elongate, narrow, highly convex, turned up somewhat at 
the posterior end. Axial lobe low, not sharply outlined, without rings, 
a trifle more than one third the total length. Pleural lobes steep- 
sided, with narrow concave border, which does not extend around the 
posterior end. No traces of ribs, except for the anterior one. Surface 
of pleural and axial lobes crossed by wavy cracks which have a course 
approximately at right angles to the axis. Doublure wide, especially 
at the posterior, where it extends half way to the front, and marked 
by deep but widely separated terrace lines. 

Measure ments: — The largest pygidium is 73 mm. long, and about 
56 mm. wide. The smallest is 22 mm. long, and 21 mm. wide. In the 
large specimen the axial lobe is 25 mm. long. In the small one it is 
8 mm. in length. 

Horizon and Locality:— Only three pygidia of this species have 



104 bulletin: museum of comparative zoology. 

so far been found: two by Dr. E. W. Shuler in 1914 and one by the 
writer in 1917. All came from the middle of the Holston in the 
McNutt quarry at Sharon Springs, Bland Co., Va. Cotypes (M. C. Z. 
1,587, 1,588). 

Hyboaspis depressa, sp. nov, 
Plate 5, fig. 1, 2. 

Among the trilobites collected from the Chazy in 1919 is a consider- 
able number of pygidia which resemble those of Isotclus platyviargina- 
his Raymond but which have the short axial lobe of Hyboaspis. They 
differ from H. shidcri in having a subcircular outline and depressed 
form. 

Unfortunately no entire specimens were found, and there is nothing 
to indicate whether any of the detached cephala in the collection may 
belong with them. Isoidvs horrisi, I. platymargiuatus, Nileoides 
perkinsi, and other more or less large smooth specimens were found in 
the same strata. Since the pygidium of Nileoides perkinsi is unknown, 
it might be suspected that these shields belong to that species, were 
they not all much too large. 

Cephalon and thorax unknown. The pygidium has roughly the 
outline of a truncated circle, the greatest width being behind the 
anterior margin. Surface of the central portion evenly convex, sloping 
gently into a wide concave border. Axial lobe not much elevated, 
wide at the front, short, tapering rapidly. Dorsal furrows shallow. 
Half way down the slope there is another furrow, Aariously developed 
on different specimens, but usually rather faint, especially behind the 
axial lobe. It is approximately parallel to the margin. The surface 
of the shell is co\ered with very narrow cracks which are somewhat 
wavy, but in general transverse to the axis. 

Measurements: — A small pygidium is 35 mm. long, about 42 mm. 
wide at the anterior end; the axial lobe is 14 mm. long, and 16 mm. 
wide at the front. A larger one is 56 mm. long, about 66 mm. wide; 
and the axial lobe is 20 mm. long. 

Horizon and Locality:— This species is fairly common in the reef 
at the base of the Upper Chazy, two miles southeast of Chazy, N. Y., 
where ten pygidia (including the cotypes M. C. Z. 1,683, 1,684) were 
collected by the writer. A specimen from the same horizon on Isle 
La Motte, Vt., collected by Professor Hyatt, has long been in the 
M. C. Z., and another one, probably from the same horizon, was 
found in Prof. H. M. Seeley's collection at Middlebury College. 



baymoxd: ordoviciax trilobites. 105 

Illaenidae Corda. 
Illaenus fraterkus Billings. 
Illaenus fraiernus Billings, Pal, foss. Canada, 1865, 1, p. 276, fig. 262a, b. 

This species is readily recognized by the subhemispheric form of 
the cranidiuni, the straight dorsal furrows, and the nearly smooth 
surface. The profile is much more nearly a semicircle than that of 
any other of the species from Newfoundland. The surface of the 
cranidiinn is covered with fine cracks but thej- are finer, farther apart, 
and less continuous than those of /. consiviilis and much less con- 
spicuous. 

The axial lobe of the pygidium is low, and the dorsal furrows faint. 

Horizon and Localify: — Billings listed this species from division L, 
Point Rich, N, Table Head, and the conglomerates of P, four miles 
northeast of Portland Creek, Xfld, but Professors Schuchert and Twen- 
hofel found it only in their zones 10 and 11 at Point Rich. 1 have 
not seen it elsewhere. 

Illaenus consimilis Billings. 

Illaenus cotisimilis BiUings, Pal. foss. Canada, 1865, 1, p. 277, 331, fig. 263a-c, 
317, 318a. 

This species was fully described by Billings, and the present collec- 
tion has brought out no new information. It is one of the common 
fossils at its horizon and the cranidia are very readil;\- recognized, since 
they are covered with coarse elevated striae and cracks roughly 
parallel to the anterior margin. The top of the cranidium appears 
somewhat concave, since the palpebral lobes are at an elevation higher 
than the glabella. As shown in Billings's figure, the free cheeks have 
broadly roimded genal angles and show a curious indentation in the 
margin below the eye. The eyes are situated so far back as practically 
to reach the posterior border. 

The pygidium shows wrinkles similar to those on the cranidium, 
but they are less crowded and are found principall\' on the anterior 
and lateral portions, the region back of the low axial lobe being smooth. 

Horizon and Localify: — Billings recorded this species from division 
L, Point Rich, and ]\I and N, Table Head, Newfoundland. Pro- 
fessors Twenhofel and Schuchert collected it in their zones M2, Ni, 
and N2, and in the Isolated limestone, all at Table Head, Nfld. 1 have 
not seen the species elsewhere. 



106 BTLLETIX: MUSEUM OF COMPARATIVE ZOOLOGY. 

Illaenus valvulus, sp. nov. 
Plate 4, fig. 13, 14. 

Cranidium short, high, and very smooth. The dorsal furrows are 
very short and show as indistinct depressions near the posterior 
margins, rather than regular furrows. The frontal slope is steep, 
evenly convex, and on the top the glabella is elevated slightly above 
the cheeks. The palpebral lobes are large and close to the posterior 
margin. The shell is smooth and polished, but where the surface is 
exfoliated there seems to be an inner shell with minute and rather 
sparsely scattered puncta. 

Only one segment of the thorax, the posterior one, has been seen. 
From it one would judge that the .segments were \ery short, flat, and 
that the axial lobe was wide. 

The pygidium is almost flat, very smooth, and the axial lobe is 
indicated only at the anterior border. The surface shows a few very 
fine wrinkles and puncta. 

Measurements: — A cranidium is 5 mm. long in projection and 11 
mm. over the curve. It is 13.5 mm. wide at the palpebral lobes. The 
last segment of a thorax is 7.5 mm. wide. A pygidium is (3 mm. long, 
and 16 mm. wide. 

Horizon and Locality: — A rare species, found only in the Holston 
in the Catawba Valley, north of Salem, Va. Cotvpes (M. C. Z. 1,651, 
1,652). 

Illaenus lautus, sp. nov. 
Plate 4, fig. 11, 12. 

Cranidium short, high, with a ver\- steep frontal slope. The dorsal 
furrows are narrow but distinct and converge throughout the greater 
part of their courses, turning outward at the anterior ends. The 
glabella is on the same level with the cheeks and exfoliated specimens 
show a very faint median ridge which extends to the anterior margin. 
Close to the posterior margin, on what woukl be the neck-ring were 
there a nuchal furrow, is a small median pustule. The eyes are of 
medium size, situated close to the posterior margin. The test, so far 
as it is preserved, appears to be smooth. 

Measurements: — A cranidium is 7 mm. long (in projection) and 
15 mm. measured over the curve. It is 16 mm. wide at the palpel)ral 
lobes. All of the specimens are small. 

Horizon and Locality: — This is a rather rare species found so far 



RAYMOND: ORDOVICIAN TRILOBITES. 107 

only in the Holston at the Ross Repubhc quarr\-, three miles southeast 
of Knoxville, Tenn., and in the Holston in the Catawba Valley, north 
of Salem, Va. The cotypes (M. C". Z. 1,653, 1 ,()o4) are from the former 
locality. 

Illaenus fieldi, sp. nov. 
Plate 7, fig. 1-4. 

A large Illaenus with subhemispheric cephalon, deep dorsal furrows, 
and small eyes. The furrows are strongly marked, wide and deep. 
In their course they first converge for a short distance then become 
roughly parallel, and near the top of the anterior slope, turn rather 
sharpl\' outward. The median lobe of a single exfoliated specimen 
from the Holston in the Catawba \'alley, Va., shows four pairs of 
scars, corresponding to glabellar furrows. The eyes are small, situated 
very close to the posterior margin, and the palpebral lobes are depressed 
below the surface of the glabella and fixed cheeks. The surface of the 
shell shows numerous shallow puncta, and around the anterior margin 
there is a slightly elevated striated rim. 

No thorax which can with al)solute certainty be assigned to this 
species is known. 

The pygidium is of a \er\- common t\pe, depressed con\ex, with 
short, wide, low axial lobe, and the sides sharply truncated so that 
they make an angle of about 115° with the anterior margin. The 
surface is covered with closely packed, fine wrinkle-like raised lines. 

Measurements: — A cranidium is 20 mm. long in projection, and 
about 36 mm. wide at the palpebral lobes. The length measured o\er 
the curve is 35 mm. Another cranidium is 21 mm. long in projection 
36 mm. over the curve; and 37 mm. wide at the palpebral lobes. A 
small pygidium is 8 mm. long, 13 mm. wide at the front, and 14.5 mm. 
wide at the back. A larger one is 17 mm. long, about 25 mm. wide at 
the front, and about 27 mm. wide at the back. 

This species is most nearly allied to Illaenus americanus, differing 
from that species chiefly in the greater curvature of the dorsal furrows. 
The dorsal furrows of /. americanus bow slightly outward in the middle 
of their course, whereas those of /. fieldi bow inward. The similarit\' 
in con\exity of head, shape and position of e\es, and of pygidium in 
the two species is rather remarkable. In shape of cranidium and 
course of glabellar furrows, Illaenus marginalis approaches /. fieldi, 
but the eyes of the latter species are very much smaller than those of 
the former. 



108 bulletin: museum of comparative zoology. 

Horizon and Localitij: — This is the most common Illaenus in the 
Lower Middle Ordovician of Virginia and Tennessee. The cotypes 
(M. C. Z. 1,658-1,660) are from the Holston in the Catawba Valley, 
north of Salem, Va. It is also common in the Holston at the Hoge 
farm, Bland Co., Va., and occurs in the same formation at the McNutt 
quarry near Sharon Springs, Bland Co., near Ceres, Bland Co., Va., 
and at Concord, Tenn. It is \ery common at the base of the Liberty 
Hall at Lexington, Va., and fairly common in the Ottosee at Speers 
Ferry and north of Mendota, Va. A number of specimens were col- 
lected from the Lenoir, southeast of Knoxville, Tenn., and one from 
the Pearisburg at Pearisburg, Va. Specimens of pygidia believed to 
belong to this species Avere found in the shale at the base of the Ottosee 
at Luttrell, Tenn., and a thorax and pygidium near the base of the 
Holston at Lone Mountain, Tenn. Some poorly preserved specimens, 
not positively identified, come from the Ottosee near Goodwins Ferry 
on the New River, Va . Specimens have been collected by Profs. S. L. 
Powell, R. M. Field, E. W. .Shuler, and the writer. 



Illaenus bayfieldi Billings. 

Illaenus bayfieldi Billings, Canad. nat. geol., 1859, 4, p. 369, fig. 4-6. Geol. 
Canada, 1863, p. 133, fig. 65a-c. Raj-mond, Ann. Carnegie mus., 1905, 
3, p. 348, pi. 13, fig. 11, 12. 7th rept. Vermont state geol., 1910, pi. 35, 
fig. 11, 12. 

Billings mentioned this species as the only Illaenus known to him, 
entire specimens of which were common. Sir William Logan must 
have been unusually fortunate in his visit to the Mingans in 1859 as 
subsequent collectors have not found the species particularly^ abundant, 
and it has not been found outside those islands. Professor Twenhofel 
collected a very excellent enrolled specimen from Harbor Island, and 
two cranidia on the west of Quarry Cove (Quarry Island). It is listed 
from zone A3 of Schuchert and Twenhofel's section only. 

The principal characteristics of this species are the short, wide, 
evenly convex head, short, straight, rapidly converging dorsal furrows 
and small eyes, situated very far apart and close to the posterior 
margin. 

Measvrcmenh': — The following measurements were taken from the 
specimen collected b\- Professor Twenhofel. Length of cephalon (in 
projection) 14 mm., along the curve 24 mm. Width at genal angles 
34 mm.; at palpebral lobes 28 mm. 



RAYMOND: ORDOVICIAN TRILOBITES. . 109 

Illaenus margixalis, sp. nov. 
Plate 7, fig. S, 9. 

A large lllaeniis with a high, evenly convex cranidium which is 
rather flat on top. The dorsal furrows are wide and shallow, far apart 
at the posterior margin. Their courses con\erge to a point opposite 
the anterior margins of the eyes, and there turn outward and fade out. 
The top of the glabella is about even with the palpebral lobes. These 
latter are large, and situated about one half their own length from the 
posterior margin. Around the anterior margin is a raised, striated, 
convex border. No well-preserved free cheek has been seen, in spite 
of the fact that this is a common species. 

The associated pygidium is depressed convex, with wide, faintly 
outlined axial lobe. 

Measurements: — Length of cranidium (in projection) 22 mm. o\-er 
the curve 47 mm.; width at palpebral lobes 44 mm., length of a palpe- 
bral lobe 7 mm. Length of a pygidium IS mm., width 34 mm.; width 
of axial lobe at front 13 mm. 

Horizon and Locality: — Numerous cranidia and pygidia of this 
species were collected by Professors Schuchert and Twenhofel in their 
zones 10 and 11 at Point Rich, a few specimens in their zone ]Mi at 
Table Head, and numerous small ones in the Isolated limestone at 
Table Head, Nfld. Professor Hyatt obtained some rather poor 
fragments of the same species at Port au Port, Nfld. Types in the 
Yale University Museum. 

Illaenus alveatus, sp. nov. 

Plate 7, fig. 5. 

This species is remarkable because it has a narrow concave brim on 
the front of the cranidium. The cranidium is short, high and wide, the 
front very steep, almost vertical. The dorsal furrows are short, 
shallow, and narrow, and after first con\-erging slighth' for a short 
distance, turn outward and become lost at the top of the anterior slope. 
The glabella is scarcely raised above the general surface and of course 
merges into the general even convexity of the front. The palpebral 
lobes show that the eyes were large, close to the posterior margin, and 
distant from the dorsal furrows. The anterior brim is narrow, being 
merely a narrow trough with upturned rim. The specimens are largely 
exfoliated, but such patches of test as are retained show no surface 
markings. 



110 bulletin: museum of comparative zoology. 

On the same small fragment of limestone with one of the eranidia is 
a fragment of a thorax showing the greater part of six segments and a 
partially ex-foliated pygidium. They are of the right size to have 
belonged to this cranidium and it is presumed that they are part of the 
same specimen. The axial lobe of this thorax is rather wide for an 
Illaenus, and only slightly convex. The pleural lobes are flat near 
the dorsal furrows, and then abruptly- deflected to form steeply sloping 
sides. The pygidium is short antl wide with a short, low axial lobe 
which is rather sharply outlined. The surface of the test shows a few 
small irregularly scattered puncta. 

Mcasurrments: — One cranidium is 8 mm. long (in projection), and 
19 mm. wide at the axial lobes. The six segments of thorax associated 
with this cranidium are 6 mm. long, the w^idth 20 mm. at the front, and 
the axial lobe 8 mm. wide. The pygidium is 7.5 mm. long, and 15 mm. 
wide. The axial lobe is 6 mm. wide at the front. 

The very low^ glabella, lightly impressed glabellar furrows, and the 
presence of an anterior brim separate this species from other described 
species. The latter characteristic in fact, makes this species unique 
among the Illaeninae, and to be strictl\' logical, the species should 
perhaps be transferred to the Bumastinae, where, however, it could not 
be assigned to any established genus. 

A closely allied species is Illaenus wcavrri Reed (Quart, journ. Geol. 
soc. London, 1909, 65, p. 142, pi. 6, fig. la-lc, 2, 3) from the Llandeilo 
of Counties Mayo and Galway, Ireland. It has the same shape, and 
particularly the same very abrupt deflection of the front of thecephalon, 
but lacks the curious lip-like brim. 

Horizon and Locality: — This is a \ery rare species, collected by 
Professors Schuchert and Twenhofel in their zone 10 between Garga- 
mella Cove and Point Saunders, Nfld., and in zone 1 1 at Point Rich, 
Xfld. Holotype in the Yale University Museum. 



Illaenus protuberans, sp. nov. 

Plate 8, fig. 1, 2. 

Although but a single cranidium of this species has been found, it 
differs so greatly from any other known species of the true Illaenus 
that it is quite within the bounds of propriety to describe it. The 
cranidium is small, high, protuberant in front. Viewed from above, 
the outline is triangular, the median lobe elevated above the cheeks 
and having very much the same form as the same lobe in Amphilichas 



RAYMOND: ORDOVICIAN TRILOBITES. Ill 

prominulus (p. 126). The palpebral lobes are very indistinctly shown 
by the specimen but appear to be small and close to the posterior 
border. The surface seems to be smooth, except for terrace lines along 
the anterior border. 

Measurenicuis: — Length of cranidium 9 mm., width at palpebral 
lobes, about 11 mm.; width of axial lobe at posterior margin 5.75 mm. 

The only species with which this one can be compared is Illacnus 
ronifrons Billings, which is found in the Upper ('hazy of the Mingan 
Islands. That species, however, has the long, elevated eyes of a 
Thaleops, whereas the specimen from Virginia is surely an lllaenus. 
Except for the eyes and size, the species are much alike. 

Horizon and Locality: — The single specimen (Holotype M. C. Z. 
1,661) was collected from the granular limestone at the top of the 
Holston at the Thomas farm, three miles northeast of Blacksburg, Va. 

Illaenus tumidifrons Billings. 
lllaenus tumidifrons Billings, Pal. foss. Canada, 1865, 1, p. 278, fig. 26-la, b. 

This species was very fully described by Billings, and is easily 
recognized by its very tumid cephalon. The e\es are a little larger 
and a little farther back than in Billings's 264a. Even small speci- 
mens have ten segments in the thorax, an extended specimen 5 mm. 
long having the full number. 

Horizon and Localiiy: — Billings's original specimens were from the 
conglomerates of Division Pat Cow Head, Nfld. Professors Schuchert 
and Dunbar obtained numerous cranidia and p\gidia and two entire 
specimens from the same locality. It has never been reported else- 
where. 

Illaenus consobrinus Billings. 

lllaenus consobrinus Billings, Pal. foss. Canada, 1865, 1, p. 280, fig. 266a, b. 

Professors Schuchert and Dunbar obtained ten cranidia of this 
species from the type-locality at Cow Head, Nfld., where it occurs in 
pebbles in the Cow Head conglomerate. 

Illaenus vl\tor, sp. nov. 

Plate 6, fig. 16, 17. 

A large lllaenus, represented by four nearly complete specimens, 
three of which are natural moulds, and one partially enrolled retaining a 
part of the test. 



112 bulletin: museum of comparative zoology. 

All are somewhat flattened, so that the natural curvature cannot be 
determined. The cephalon is very wide, for e\en with the free cheeks 
lacking, the palpebral lobes extend beyond the margin of the thorax. 
The dorsal furrows are deep at the posterior margin, grow fainter as 
they converge forward. The glabella is ovate, depressed con\ex, \'ery 
wide at the back. 

The thorax has ten segments and a very wide axial lobe. 

The pygidium bears a short, wide axial lobe which is only partly 
encircled by the dorsal furrows. The pleural lobes have straight sides 
which make an angle of about 105° with the front. 

The enrolled specimen is unique in that it is the only American 
illaenid I have ever seen which retains the hypostoma. This organ is 
not exactly in place, but is still present on the median line of the 
glabella. It presents no unusual characteristics, but is very small, 
only about one third the apparent length of the cephalon. 

This species seems to be most like Illaemis latiaxiaius Raymond and 
Narraway. The two agree in the very wide axial lobe, con\'ergent 
glabellar furrows, and the angle of truncation of the sides of the 
pygidium. I. viator seems to have the eyes farther apart and a shorter 
and wider cephalon. lUaenus americaniis Billings is another closely 
allied species, but has a narrower axial lobe, differently cur\-ed dorsal 
furrows, and the truncated sides of the pygidium di\'erge at a wider 
angle. 

Measurements: — The specimens are all so poorly preserved that 
only approximate measurements can be secured. The best specimen 
is 48 mm. long, 43 mm. wide at the palpebral lobes; the cephalon is 
18 mm. long; the thorax 13 mm. long; the pygidium 17 mm. long, and 
30 mm. wide. The cephalon of the enrolled specimen is about 25 mm. 
long (much flattened), and the hypostoma 7 mm. long, and 9 mm. wide. 

Horizon and Locality: — ■ The specimens are from a thinl\' bedded 
sandstone, determined by Professor Schuchert to be of late Richmond 
age, on the west shore of Long Point, Nfld. Professors Schuchert and 
Dunbar, collectors, 1917. Cotypes in the Yale University Museum. 

Illaenus, sp. ind. 

Two imperfect cranidia from the lower part of the Richmond, New- 
foundland are of interest only from the fact that the genus is not else- 
where recorded from this horizon. 

The better specimen, found on the shore opposite Black Duck Bay, 
can hardly be distinguished from a cranidium of Illaenm americaniis, 



RAYMOND: ORDOVICIAN TRILOBITES. 113 

except that the dorsal furrows converge somewhat more sharply in the 
first 2 mm. of their courses. The profile is also different, the front 
being much less incurved. 

The other cranidium found near Long Point lighthouse is very 
badly preserved, but may possibly be a small specimen of lUaenus 
viator. 

Thaleops clavifrons (Billings). 

Illaenus clavifrons Billings, Canad. nat. geol., 1859, 4, p. 379. 
Illaenus vindex Billings, Pal. foss. Canada, 1865, 1, p. 179, fig. 160. Raymond, 
Ann. Carnegie mus., 1905, 3, p. 353, fig. 2. 

This species was but briefly described by Billings, as he considered 
it as possibly only a variety of Illaenus conifrons. Later, however, he 
described more perfect specimens under another name. The two can- 
not occur together very regularly, for Professor Twenhofel collected a 
large number of Thaleops clarifro)is, but did not bring back a single 
fragment of /. conifrons. Both species are probabh- to be referred to 
Thaleops, though the eyes of /. conifro7is are not yet fully known. 

Cranidium quadrate, dominated by the glabella which has a very 
steep frontal slope. The dorsal furrows are parallel from the posterior 
margin half way to the front, there turn abruptly outward and finally 
converge again around the front of the glabella, though very faint 
there. The top of the glabella is nearly flat, and on the constricted 
neck-portion are traces of two or sometimes three pairs of furrows. 
These show much more plainl\' on some specimens than on ethers and 
generall\- take the form of slight swellings. The cheeks are depressed 
below the surface of the glabella, but the long palpebral lobes raise the 
eyes abo\e them. The surface of small specimens is covered with 
numerous coarse puncta. In large specimens these puncta become 
relati\ely large, somewhat irregular depressions which give the surface 
a unique appearance. Free cheeks and thorax unknown. Pygidium 
convex, truncated at the sides, with high axial lobe, and the same 
surface markings as the cranidium. 

Measurements: — A small cranidium is 6 mm. long (in projection), 
and 11 mm. wide at the palpebral lobes. A cranidium of medium size 
is 10 mm. long (in projection) 17 mm. long over the curve; and 21 
mm. wide at the palpebral lobes. The glabella is 5.5 mm. wide at the 
back, and 9 mm. wide at its widest point near the front. A large 
cranidium is 15 mm. long in projection, and about 34 mm. wide at the 
palpebral lobes. A large pygidium is 18 mm. long, 27 mm. wide at 
the front, and 30 mm. wide at the back. ■> 



114 bulletin: museum of comparative zoology. 

The ornamentation is sufficient to distinguish this from any other 
described species of Thaleops. 

Horizon and Locality: — This is a common species in zones A3 and 
A5 of the Mingan formation of Upper Chazy age in the Mingan Islands. 
Professor Twenhofel collected it on Large Island, Harbor Island, the 
west side of Quarry Cove, and Panoquet. 

Bumastus erastusi Raymond. 

Illaenus erastusi Raymond, Ann. Carnegie mus., 1905, 3, p. 351, pi. 13, fig. 8, 9. 
Bumastus erastusi Raymond, Ann. Carnegie mus., 1910, 7, p. 71. 7th rept. 

Vermont state geol., 1910, p. 229, pi. 35, fig. 8, 9. 
f Illaenus crassicauda Hall, Pal. N. Y,, 1847, 1, p. 24, pi. 4 bis, fig. 13. 

This species was described originally from the strata at the base of 
the Upper Chazy on Valcour Island, N.Y. Professor Twenhofel 
found a considerable number of specimens on the Mingan Islands 
which are probably to be referred to it, though there are some differ- 
ences. The dorsal furrows are shorter on the specimens from the 
Mingan Islands than on those from New York, and the pits ahead of 
the furrows, which are so prominent on the original specimen, are small 
and inconspicuous. 

The pygidia from both localities agree in being elongate, highly 
convex, no axial lobe defined except by the depressions at the anterior 
margin, and in showing a faint concavity in the profile of the posterior 
slope. 

One specimen collected by Professor Twenhofel has the cranidium 
and pygidium connected by a somewhat crushed thorax, so that the 
correctness of the association of the two shields is assured. 

This species is associated both at Valcour Island and in the Mingan 
Islands with Bumastus glohosus. It has a less highly elevated cranid- 
ium than that species, and a much longer pygidium. 

Horizon and Locality: — This species has been found in the Middle 
and Upper Chazy, at the lower end of Lake Champlain in New York, 
and Vermont, and in zone A5 (Upper Chazy) on Bald Island and Large 
Island, Mingan Islands. 

Bumastus porrectus, sp. nov. 
Plate 8, fig. 7, 8. 

Bumastus trentonensis Clarke {non Emmons), Geol. Minn., 1897, 3, pt. 2, p. 
720, fig. 32 (no?i fig. 30, 31, 33). Grabau and Shimer, N. A. index fossils, 
1910, 2, p. 298, fig. 1610b. 



RAYMOND: ORDOVICIAN TRILOBITES. 115 

When Mr. Xarraway and I wrote of the history and status of the 
names Buiiia.stii.s- trcutoncnsis and Illucnus trintottcniiis we somewhat 
weakly intimated that there might be some trilobite of this family 
which could use the name trentoncnsis, but the more the question is 
studied the more certain it becomes that the only proper method is to 
suppress the name entirely. Such action leaves bumastids which are 
rather common at Trenton Fails and elsewhere without names, a 
condition which I shall endeavor to remedy forthwith. 

The entire animal is about one half longer than wide, slender, with 
slight traces of dorsal furrows. 

The cephalon is somewhat plumper than the quarter of a sphere, 
evenly convex, and ^•estiges of dorsal furrows are seen in \er\- faintly 
visible traces of lunettes. The e\es are small, situated far back and 
far apart. The free cheeks are small and so nearly vertical in position 
that they are concealed by the eyes when viewed from above. 

The thorax has ten segments, is evenly convex, and has a \ery wide 
axial lobe which is delimited by broad, shallow, dorsal furrows. 

The pygidium is short, smooth, and evenly con\ex, without any 
trace of an axial lobe. 

The surface of the entire test is smooth, the only ornamentation 
being faint concentric wrinkles on the anterior margins of both 
cephalon and pygidium. 

Mra.siarmnifs: — P^ntire length of the type, about 23 mm. (cephalon 
slightly displaced). Width of cephalon 13 mm., length in projection 
9 mm. o\er the curve 12 mm.; width at the palpebral lobes 12 mm. 
Length of thorax 6.5 mm., width at front 12.5 mm., width at back 
11.5 mm.; width of axial lobe at front 9 mm. Length of pygidium 
8.5 mm., width 11 mm. 

This species differs from most other described bumastids in the 
almost total absence of dorsal furrows from the cephalon. Its nearest 
ally, Bumasfus miUrri (Billings), frequently has the lunettes equally 
obscure, but in that case the dorsal furrows usually appear as shallow 
depressions at the posterior margin. Bumasius milleri has a wider 
cephalon than B. porrrctvs, so that the entire animal is less slender, 
and has the appearance of tapering much more rapidly toward the 
pygidium. It would, however, be almost impossible to distinguish 
isolated cranidia and pygidia of the two species. Bumasius milleri 
always has nine thoracic segments. B. porrcctus usually has ten, but 
may have only nine. 

Horizon and Locality: — The type and the specimen figured by Dr. 
Clarke in the Paleontology of Minnesota are from the upper third of 



116 bulletin: museum of comparative zoology. 

the Trenton at Trenton Falls, N. Y. The type (M. C. Z. 728) was 
collected by Dr. C. D. Walcott. 

BuMASTUS HOLEi Foerstei 

Plate 8, fig. 5, 6. 

Butnastus holei Foerste, Bull.Denisonuaiv., 1920, 19, p. 214, pi. 21, fig. 15a, b; 
pi. 22, fig. a, b. 

Entire animal obovate in outline, evenly con\'ex, the cephalon 
considerably larger than the pygidium. The cephalon is evenly con- 
vex, with a slight longitudinal median depression. The dorsal furrows 
are represented by large depressed lunettes from which, on the cast, 
shallow furrows extend straight back to posterior margin, whereas on 
testiferous specimens only the lunettes show. The eyes are small, 
very far apart, close to the posterior margin. The free cheeks are 
small and so nearly vertical in position as to be hardly visible from 
above. There is a minute median pustule just in front of the narrow 
obscure nuchal furrow and the surfaces of exfoliated cranidia are 
covered with rather coarse puncta; where the shell is preserved, it is 
granulose. 

The thorax has ten segments. The axial lobe is very wide and the 
dorsal furrows very shallow. The surface is granulose. The pygid- 
ium is about four fifths as long as wide, e\enly convex, without trace 
of axial lobe. Exfohated specimens show a median longitudinal 
furrow which becomes deeper posteriorly and at the anterior end faint 
traces of four or five segments, behind which are two large faintly 
raised areas, one situated on either side of the median groove. These 
latter markings probably indicate the position of the attachment of 
the dorsal (extensor) muscles. The exterior surface is faintly granu- 
lose and has a few delicate, raised lines parallel to the anterior margin. 
When exfoliated, the surface is punctate, like the cephalon. 

Measurements: — The largest entire specimen in the collection is 
54 mm. long, 32 mm. wide at the genal angles; and 27 mm. wide at the 
pygidium. The cephalon is 20 mm. long in projection and 31 mm. 
over the curve. The inner edges of the lunettes are 17.5 mm. apart 
and the width at the palpebral lobes is 29 mm. 

The plesiotype is 37 mm. long, 24 mm. wide at the genal angles; 
20 mm. wide at the pygidium. The cephalon is 13 mm. long in pro- 
jection, 22 nun. wide at the palpebral lobes, and the lunettes are 12 mm. 
apart. The thorax is 13 mm. long, 23 mm. wide at the front, 20 mm. 



RAYMOND: ORDOVICIAN TRILOBITES. 117 

wide at the back; and the axial lobe is 17 mm. wide at the front. The 
pygidium is 16 mm. long, and 20 mm. wide. 

This species is most closely allied to Bvmastiis billingsi Narraway 
and Raymond and differs only in possessing a small median tubercle, 
fainter and straighter dorsal furrows, and in the very punctate appear- 
ance of the internal cast of the cephalon and pygidium. These puncta 
have not, however, been seen on specimens from localities other 
than Trenton Falls, X.Y. Specimens retaining the test resemble B. 
porrcctus, the lunettes being faint and the posterior portions of the 
dorsal furrows concealed, but the entire animal is less slender and 
there is a greater disparity between the sizes of the cephalon and 
pygidium. 

Horizon and Locality: — The M. C. Z. contains fi\e more or less 
complete specimens from the Trenton at Trenton Falls, collected by 
Dr. C. D. Walcott many years ago, but it is not by any means common 
there. In the Kimmswick at Mincke, St. Louis Co., ]Mo., it seems to 
be one of the most common trilobites and numerous detached shields 
were collected there and at Glencoe, Mo., bv Dr. D. C. Barton. The 
plesiotype (M. C. Z. 715) is from Trenton Falls. Dr. Foerste's speci- 
mens, which ha^e been described since the above was written, were 
found in the Kimmswick limestone on Sanders Branch, Ralls Co., Mo. 



BuMASTUS GLOBOSUS (BiUiugs). 

Illaenus globosus Billings, Canad. nat. geol., 1859, 4, p. 367, fig. 1-3. Geol. 

Canada, 1863, p. 133, fig. 64a-c. Raymond, Ann. Carnegie mus., 1905, 

3, p. 350, pi. 13, fig. 6, 7. Grabau and Shimer, N. A. Index fossils, 1910, 

2, p. 294, fig. 1605a-c. 
Bumastus globosus Raymond, Ann. Carnegie mus., 1910, 7, p. 71, pi. 19, fig. 9. 

7th rept. Vermont state geol., 1910, p. 228, pi. 35, fig. 6, 7; pi. 39, fig. 9. 

Proc. and Trans. Roy. soc. Canada, 1912, ser. 3, 5, sec. 4, p. 120, pi. 3, 

fig. 3. 

This is one of the most common trilobites in the Chazy along Lake 
Champlain, and is equally abundant in the typical locality for the 
species, the Alingan Islands. Its very abundance has produced a 
tendency to rather loose reference of all Chazyan bumastids to this 
species. 

As with other members of the family, the dorsal furrows are very 
characteristic of the species. Billings states that on the type they 
extend only one third the length of the cephalon, which is true if he had 
reference to a measurement over the cur^•ature, but not if compared 



118 bulletin: museum of comparative zoology. 

with tlie actual length, of which they equal about one half. Billings's 
description of them as subparallel is also true onl\- in a most general 
sense, for they are distinctly con\ergent in all specimens. Each fur- 
row is approximately straight through the greater part of its course, 
but turns outward at both ends. On some the furrows appear 
straighter and more nearly parallel than others, the differences arising 
largely from the shape and depth of the lunules, and the presence or 
absence of the dorsal test. 

Billings was unable to make out the outline of the fixed cheeks of 
his specimens. As shown by material both from the Mingan Islands 
and Chaz\-, N. Y., these cheeks are small, but extend outward l>eyond 
the eyes. The facial suture turns abruptly outward at the back of the 
eye, runs nearly parallel to the posterior margin for a short distance, 
then graflually approaches it. 

There is considerable difference in the size attained at different 
localities. Billings's type seems to be typical of those found at the 
Mingan Islands, although Professor Twenhofel found one or two 
cranidia which were larger. Specimens from the Chazy in the Cham- 
plain ^'alley are generally small, but in the reefs at the base of !he 
Upper ( 'hazy, both at Chazy and \'alcour Island, numerous large shields 
are found, some more than twice the size of those from the Mingan 
Islands. 

Measurements: — Billings gives the following measurements of the 
type: — Length of cephalon (on the curvature) 1 inch (25 mm.), 
measured from the middle of anterior to middle of posterior margin 
9 lines (IS mm.) ; length of thorax and pygidium, each 9 lines (18 mm.). 
The largest cranidium from the ^Mingan is 32 mm. o^•er the cur^-ature, 
or 23 mm. long. The largest from the reef at Chazy is 40 mm. long 
and one from Valcour Island has the same length. Measured over the 
curvature, the latter is 55 mm. long. 

Horizon and Loeality: — Billings cited this fossil from the "Mingan 
Islands, and also Island of Montreal, Chazy." Schuchert and Twen- 
hofel report it from zones A 3-5 of the Mingan formation (Upper 
Chazy) on the Mingan Islands. It is fairly common throughout the 
Chaz\- in the Champlain Valley, but most abundant and of largest 
size at the base of the Upper Chazy. 

Small cranidia and pygidia which appear to l)elong to this species 
are common in the Lenoir at Lenoir Cit\- and one mile east of Bluff '! 

City, Tenn. 



RAYMOND: ORDOVICIAN TRILOBITES. 119 

BuMASTUs COMES, sp. nov. 

Plate 7, fig. 7. 

Illaenus globosus Raymond {non Billings), Ann. Carnegie mus., 1905, 3, pi. 13, 
fig. 6 {non fig. 7). 

This trilobite occurs commonly in the Chaz\' associated with B. 
globosus, from which 1 ha\e not previously' differentiated it. 

Cephalon highl;)- convex, with steep anterior and lateral profiles. 
The eyes are small, situated far apart, and close to the posterior mar- 
gin. The short dorsal furrows are arcuate, arise back of the eyes and 
run inward on a smooth curve to the narrow lunules, then turn slightly 
outward. The doublure is strongly striated, and a broad band of 
terrace lines rises high on the slopes of the cephalon. The test on the 
upper surface is finely punctate. 

Thorax and p;\gidium unknown. 

This species is more likely to be confused with Bumastus globosus 
than any other. Billings stated that the dorsal furrows in that species 
were subparallel, a little curved outward at the anterior extremities. 
Specimens from the Mingan Islands agree with this description, but 
the furrows are not strictly parallel, there being a slight convergence. 
The median parts of the furrows are nearly at right angles to the 
posterior margin, whereas in B. comes, the furrow is throughout its 
course decidedly curved. In profile, size, con\exity, and proportions, 
the cephala of the two species are very much alike. 

Measurements: — The holot^pe (M. C. Z. 1,608) is 20 mm. long from 
front to back (17 mm. in projection), the width is 28 mm.; and the 
width at the palpebral lobes 23 mm. Two other complete cephala 
have practically the same measurements. 

Horizon and Locality: — All of the specimens which are positively 
identified as this species (nine in number) are from the pasture three 
miles east of Chazy, N. Y., near Little Monty Bay. 

Bumastus aplatus, sp. nov. 
Plate 8, fig. 3, 4. 

Cranidium depressed, convex, smooth, with short, converging, 
faintly impressed furrows. The palpebral lobes project but slightly, 
indicating rather long, very narrow eyes. The length is only three 
fourths the breadth at the palpebral lobes, suggesting a short cephalon. 

Free cheeks and thorax unknown. 



120 bulletin: museum of coaiparative zoology. 

Pygidiimi two thirds as long as wide, depressed convex, smooth, with 
no trace of raised axial lobe. The position of the notches on the 
anterior border indicate a wide axial lobe in the thorax. 

The surfaces of both shields are marked by rather widely scattered, 
fine puncta. 

The dorsal furrows of this species are fainter than those of B. cjlohosm 
and are less nearly parallel. They are not, however, so faint as those 
of several of the other species described in this paper. The long 
narrow palpebral lobes suggest B. longiops, but the eyes do not appear 
to have been so long, and, moreo\er, the dorsal furrows are entirely 
obsolete in that species. 

Measurements:— The cranidium designated as the holotype (M. C. Z. 
1,609) is 12 mm. long (11 mm. in projection) ; and 16 mm. wide between 
the palpebral lobes. The pygidium of the paratype (M. C. Z. 1,610) is 
10 mm, long, and 16 mm. wide. The smallest specimen is 4.5 mm. long 
(3.5 mm. in projection); and 5.25 mm. wide at the palpebral lobes. 

Horizon and Locality: — Cranidia and p^gidia of this species are 
very common in the upper part of the Lower Chazy in Fleury's pas- 
ture, on the southwestern part of Isle La Motte, Vt. Three speci- 
mens, two cranidia and one pygidium, were found in the Lower 
Lenoir, one mile east of Bluff City, Tenn. 



BUMASTUS LIODERMA, Sp. nov. 

Plate 7, fig. 10, 11. 

A large Bumastus for the Ordovician, with large plump shields and 
slight traces of dorsal furrows. 

Cranidium large, very convex, smooth, without traces of dorsal 
furrows on the test. On the cast there are small shallow lunettes, and 
a pair of extremely faint narrow furrows run diagonall\- outward and 
backward from the lunettes to the posterior margin. The palpebral 
lobes are small, and close to the posterior margin. Part of a free cheek 
preserved in one specimen shows that the genal angles are broadly 
rounded and that the cephalon is constricted on either side in front of 
the eyes as in many species of Bumastus. The surface is smooth 
except on the anterior slope, where there are numerous terrace lines 
which show on the test but not on the cast. 

Only unsatisfactory fragments of the thorax have been seen. 

The pygidium is large and smooth, without trace of axial lobe. 

Measurements: — A cranidium is 45 mm. long (in projection); and 



RAYMOND: ORDOVICIAN TEILOBITES. 121 

about 62 mm. wide at the palpebral lobes. Another is 33 mm. long in 
projection, about 55 mm. over the curvature, the palpebral lobes about 
43 mm. apart, and the lunettes 22 mm. apart. A small cranidium is 
18 mm. long in projection, 23 mm. over the curve, and 25 mm. wide at 
the palpebral lobes. A pygidium which probably belongs with the 
first cranidium above is 33 mm. long and 42 mm. wide. Another is 31 
mm. long and 39 mm. wide. 

This species with its almost complete lack of traces of dorsal fur- 
rows on the cephalon and small eyes is very like the Buniastns porrectus 
of the Trenton and differs from that species chiefl\- in the much greater 
size of the specimens. It differs from Bvmastus hold in lacking the 
small median tubercle on the posterior portion of the cranidium, in 
having the lunules smaller and farther forward, and the furrows run- 
ning backward from the lunules diagonally instead of straight. The 
differences from the other species of Bumastus are too obvious to 
require comment. 

Horizon and Locality: — The species is very common at the type- 
locality, the McNutt quarry near Sharon Springs, Va., where it occurs 
in the Holston. It is found in the same formation in the Catawba 
Valley, north of Salem, Va., and at the Ross Republic quarry, three 
miles southeast of Knoxville, Tenn. It is also found in the Murat at 
Lexington, Va., in the Ottosee at Speers Ferry, Va., and the Lenoir, six 
miles southeast of Knoxville, Tenn. Cotypes (M. C. Z. 1,655-1,657). 



Bumastus limbatus Raymond. 

lUaenus indeterminaius Raymond (non Walcott), Ann. Carnegie mus., 1905, 

3, p. 347, pi. 13, fig. 1, 2. 
Bumastus limhatus Raymond, Ann. Carnegie mus., 1910, 7, p. 71. 7th rapt. 

Vermont state geol., 1910, p. 230, pi. 35, fig. 1, 2. 

A single cranidium which is referred with doubt to this species was 
found in the Lenoir, six miles southeast of Knoxville. It agrees with 
B. limbahis in having a depressed cranidium and very long dorsal 
furrows, but these furrows are more curved than in the type of B. 
limbatus and more like those seen in small specimens of B. indetermin- 
atus. As only a single small specimen has been found, a more exact 
determination must be left for the future, but the occurrence of this 
type of Bumastus in the Lenoir is of interest. 

Measurements: — The cranidium is 20 mm. long. 



122 bulletin: museum of comparative zoology. 

BuMASTUs DisPASSus, sp. nov. 
Plate 7, fig. 6. 

Three segments of the thorax and the p\'gidium represent a species 
of Bumastus of a type unusual in the Ordovician, but not unlike many 
of the Silurian species. 

The thorax has a wide axial lobe which is elevated considerably 
above the narrow pleural lobes, the dorsal furrows being so deep as to 
set off the lobes distinctly. The individual segments are wide. 

The pygidium is slightly longer than wide, not highly convex, and 
possesses a wide concave border. The axial lobe is indicated only at 
the anterior margin, and the surface is apparently smooth. 

Measurements: — Three segments of the thorax, probably the last 
three, are together 11 mm. long, and about 26 mm. wide. The axial 
lobe is 30 mm. wide on the middle segment. The pygidium is 34 mm. 
long, and 33 mm. wide. 

The low long pygidium with its wide concave border serve to dis- 
tinguish this species. Bumastus indeterminatiis Walcott has a wide 
concave border on the pygidium and one might predict that the 
cephalon of B. dispassus would probably prove to be depressed convex, 
with long dorsal furrows like those of B. indeterminatus and B. limbatus. 

Horizon and Locality: — The holotype (M. C. Z. 1,639) was col- 
lected by the writer from the Holston marble at Fountain City, Tenn. 

Bumastus longiops, sp. nov. 
Plate 8, fig. 18, 19. 

A small Bumastus with smooth, evenly convex cranidium, very long, 
narrow, palpebral lobes, no trace of dorsal furrows on testiferous speci- 
mens and only faint linear lunules on casts. Thorax unknown. 

The associated pygidium is very depressed, almost flat, smooth, and 
the axial lobe indicated only on the anterior margin. 

Measurements: — A cranidium is 9 mm. long (in projection) 
12.5 mm. over the curve; and 11.5 mm. wide at the palpebral lobe. 
The largest cranidium in the collection is 14 mm. long in projection. 
A pygidium is 9.5 mm. long, and 15 mm. wide. 

The large, long, Nileus-like palpebral lobes of this species readily 
separate it from all other Ordovician species of Bumastus. 

Horizon and Locality: — This species is common in the Holston at 



RAYMOND: ORDOVKIAN TRILOBITES. 123 

the type-locality, the McXutt quarry, Sharon Springs, Va., and a few 
specimens have been found in the same formation on the Hoge farm, 
Bland Co., Va., the Ross Republic quarry, three miles southeast of 
Knoxville, Tenn., and the marble quarry one mile south of Concord, 
Tenn. Two specimens were obtained from the IVIurat at Lexington, 
Va., and a few from the top of the Holston at the Thomas farm, three 
miles east of Blacksburg, Va. It was collected first by Dr. E. W. 
Shuler, and later by Dr. R. M. Field and the writer. The cotypes are 
M. C. Z. 1,647, 1,64S. 

Proetidae Corda. 
Cyphaspis slocomi, sp. no\-. 

Plate 8, fig. 9. 

Cyphaspis girardeauensis Savage {non Shumard), Bull. 23, 111. geol. surv., 
1913, pi. 2, fig. 13. 

The cranidium only is known. 

Glabella highly convex, the central portion obovate, highest in front 
of the eyes, bordered by a narrow, deep furrow. Lateral lobes small, 
oval, two fifths as long as the glabella. Fixed cheeks narrow, dropping 
abruptly away from the glabella. Frontal border flat, separated from 
the glabella by a convex ridge of about its own width. Nuchal ring 
narrow, with a low median pustule. 

It is difficult to separate the various species of Cyphaspis. None 
has hitherto been reported from the Maquoketa, but several appear to 
be present at a somewhat higher horizon in the basal Silurian (Alex- 
andrian series). Cyphaspis girardeauensis Shumard, from the Gir- 
ardeau limestone, and C. intermedia Weller, from the Channahon, are 
species from that series which are very similar to the one here described. 
All three have glabellae of what Weller has called intermediate length, 
that is, about 80 per cent of the total length. The central portion of 
the glabella of C. girardeauensis is wider in front of the eyes than is that 
of the present species; otherwise there is no recognizable difference 
between the cranidia. The glabella of C. intermedia is of the same 
shape as that of C. slocomi, but the occipital segment of the former is 
said to be narrow and flat, considerably depressed below the level of 
the glabella, whereas in the latter it is convex and high with a median 
tubercle. These differences are admittedly small, but sufficient to 
permit a separation. 

Savage (Bull. 23, 111. geol. surv., 1913, pi. 2, fig. 13) has figured as an 



124 bulletin: museum of comparative zoology. 

example of C. girardeaucnsis, a small eranidium which has the glabella 
so narrow at the front as to agree much better with C. slocomi than with 
the former species. 

Measurements: — The eranidium of the holotype (M. C. Z. 1,692) 
is 2.5 mm. long; the distance from the front of the glabella to the 
posterior margin is 2 mm., and the glabella is 2 mm. wide in front of 
the eyes. 

Horizon and Locality: — The single specimen was collected by the 
writer in the Lower Maquoketa on a loose fragment just below the 
bridge over Sand Creek at Clermont, Iowa. 

LiCHADiDAE Corda. 

AcROLiCHAS Foerste. 

AcroUchas Foerste, Ohio journ. sci., 1919, 19, p. 402. 
Amphilichas Raymond, partim. 

In a previous paper (Ann. Carnegie mus., 1910, 7, p. 72) I called 
attention to the fact already noted by both Schmidt and Reed, that 
cephala which would answer the definition of Amphilichas were found 
associated with one type of pygidium in Russia and quite another in 
America. I remarked "It can hardly be doubted that the cranidia 
and pygidia found associated in the Chazy belong to the same genus 
and species, and it is equally unlikely that Schmidt was mistaken in 
associating the cranidia and pygidia which he referred to A. lineatus. 
The glabella of Amphilichas is one which might have been developed 
along parallel lines in different sections of the Lichadidae, and it is 
therefore possible that our American species is not congeneric with 
Amphilichas lineatus." 

Foerste describes his genus as follows : — 

Cranidia as in the European genus Amphilichas. Pygidia differing 
as follows: Three pairs of ribs, all with free tips; axial lobe narrowing 
posteriorly to an acute point which reaches the notch between the free 
tips of the posterior pair of ribs. Genotype: — Lichas cucullus Meek 
and Worthen. 

Although Foerste has done nothing to prove that the American 
species are not congeneric with the type of Amphilichas, it is quite 
probable that his new generic name will stand, for in the summer of 
1918 Schuchert and Dunbar found the pygidium of Amphilichas 
jukesii, and it proves to be very like that of A. lineatus and unlike that 
of any of the other American species referred to the genus. No com- 



RAYMOND: ORDOVICIAN TRILOBtTES. 125 

plete specimen of A. lineatus having been found, there has hitherto been 
some question about the correct association of cephala and pygidia in 
the genus. 

ACROLICHAS MINGANENSIS (BilUngs). 

Lichas jninganensis Billings, Pal. foss. Canada, 1865, 1, p. 181, fig. 163a, b. 
Lichas {Platymetopus) minganensis Clarke, Geol. Minn., 1897, 3, pt. 2, p. 753. 
Platymetopus minganensis Raymond, Ann. Carnegie mus., 1905, 3, p. 355, 

pi. 14, fig. 1-3, p. 366, fig. 7, 8. 
Amphilichas minganensis Raymond, Amer. journ. sci., 1905, ser. 4, 19, p. 378. 

Ann. Carnegie mus., 1910, 7, p. 72, pi. IS, fig. 6; pi. 19, fig. 13, 14. 7th 

rept. Vermont state geol., 1910, p. 232, pi. 36, fig. 1-3, pi. 38, fig. 6, pi. 39, 

fig. 13, 14. Grabau and Shinier, X. A. index fossils, 1910, 2, p. 308, fig. 

1619. Bassler, Bull. 2a, Geol. surv. Virginia, 1909, p. HI, figs. 7, 8, 10. 

Perkins, 8th rept. Vermont state geol., 1912, pi. IS, fig. 6. 
Lichas champlainensis Whitfield, Bull. Amer. mus. nat. hist., 1881, 1, p. 342, 

pi. 33, fig. 6-8. Brainerd and Seely, Bull. Amer. mus. nat. hist., 1890, 3, 

p. 22. 

The original localities for this species cited by Billings were the 
island of Montreal and the south side of Large Island, Mingan Islands. 
I have before me four cranidia, collected by Professor Twenhofel on 
Bald Island, Mingan Islands, in the coarse-grained white limestone of 
zone As of Schuchert and Twenhofel's section (Bull. Geol. soc. Amer., 
1910, 21, p. 692). These are somewhat more perfect than the cotypes 
figured by Billings and afford some additional information about 
specimens from the typical region. 

They show that the furrows which delimit the central lobe are not 
exactly straight, but show a slight deflection toward the side lobes at 
about the horizon of the e\'es. Neither do these furrows reach the 
neck-furrow at exactly a right angle, there being a slight outward bend 
in the last 1 or 2 mm. of the course. The dorsal furrows tiu'u \ery far 
out behind the eyes, making the side lobes roughly kidney -shaped. 
The ornamentation is rather luiiform on the four specimens, consisting 
of low rounded tubercles of about three sizes, none very large or con- 
spicuous. The largest tubercles seem to be spaced about their own 
diameter apart, with the smaller ones in more or less regular rings 
around them. Associated with the cranidia are two h\'postomata of 
the usual form for the genus. Their surfaces are smooth. 

This same species is quite common in the Holston in the Catawba 
Valley, north of Salem, Va., where both cranidia and pygidia were 
found. The cranidia show the same characteristics as those from the 



126 bulletin: "museum of comparative zoology. 

iMingan Islands. The pygidia agree with the ones found in the Cham- 
plain Valley. The axial lobe shows two rings, and tapers to a point 
behind, while the pleural lobes show three broad ribs with free pointed 
ends. 

Measur (Clients: — A cranidium from Bald Island, Mingan Islands, is 
23 mm. long, 28 mm. wide at palpebral lobes; and the median lobe of 
the glabella is 8 mm. wide at the horizon of the eyes. Another cran- 
idium from the same locality is 26 mm. long. 

A cranidium from the Catawba Valley is 28 mm. long, 34 mm. wide 
at the palpebral lobes, and the median lobe is 9.5 mm. wide at the 
horizon of the eyes. A pygidium from the latter locality is 26 mm. 
long, about 37 mm. wide, and the axial lobe is 14 mm. wide at the front. 

Horizon and Locality: — Besides the localities cited by Billings, which 
are both in the Upper Chazy, this species occurs in the Middle and 
Upper Chazy in the Champlain Valley, and, as recorded above, in the 
Holston in the Catawba Valley. The species also occurs in the 
Holston at the McNutt quarr^•, in Bland Co., Va., whence we have 
three cranidia, one collected by Dr. Shuler. A single pygidium from 
the Ottosee east of the quarries at Saltville, Va., may belong to this 
species, but is too poorly preserved for accurate identification. 

Bassler has reported it from the Liberty Hall at Lexington, Va., and 
there are fragments of an Acrolichas, possibly this species, in the 
upper part of the Holston zone with agnostids, three miles east of 
Blacksburg, ^'a. 

Acrolichas prominulus, sp. nov. 
Plate 8, fig. 11, 12. 

In the Holston at the McNutt quarry, Dr. Shuler found two im- 
perfect cranidia which differ from all other species of the genus in 
having the anterior end of the glabella somewhat drawn out and com- 
pressed laterally. The courses of the glabellar and dorsal furrows are 
practically the same as in Acrolichas mijigancnsis, but the surface is 
rougher than in that species because certain irregularly placed tuber- 
cles are considerably larger than the others. 

The prominent anterior end of the glabella of this species suggests 
A. cucullus (Meek and Worthen) but the dorsal surface shows no such 
transverse depression as is developed in that form. 

Two hypostomata found in the same c^uarry with these cranidia, 
differ from the hypostoma of A. minganensis in having much less ele- 
vated mounds on the proximal ends of the side wings, and they are 



RAYMOND: ORDOVICIAN TRILOBITES. 127 

therefore referred to this new species, though with considerable 
reservation. 

Measurements: — The more complete cranidiuni, a fragment of a 
large specimen, was apparently about 38 mm. long, and about 48 mm. 
wide at the palpebral lobes. The smaller cranidiuni was about 28 mm. 
long when complete. 

Horizon and Locality: — This species has so far been found only at 
the McXutt quarry, near Sharon Springs, and on the Hoge farm, 
both in Bland Co., Va. The cotypes are M. C. Z. 1,753, 1,754. 



Amphilichas .iukesii (Billings). 

Lichas jukesii Billings, Pal. foss. Canada, 1865, 1, p. 282, fig. 269a, b, p. 335, 
fig. 323a, b. 

The type of Amphilichas is Plat ymeto pus lineatu.f Angelin (Pal. 
Scandinavica, 1854, 1, p. 75, pi. 38, fig. 12, 12a), a species so poorly 
described and figured by its author that were it not for Schmidt's 
researches it would be absolutely unrecognizable. The cephalon is 
very simple for a lichad, the first pair of furrows extending back to the 
neck-furrow, and cutting the glabella into three plain lobes. This is 
the same type of cephalon as in the common American Acrolichas, but 
the pygidiinn found by Schmidt associated with it is much shorter than 
that of Acrolichas, has the pleural lobes extended as blunt points only, 
not in free ribs, and the axial lobe merges into the general surface. 
Professors Schuchert and Dunbar found a pygidium of this sort asso- 
ciated with cephala of Lichas jukesii, showing that it is a true Amphi- 
lichas. 

The cephalon of this species is somewhat peculiar, for although the 
majority of the specimens have glabellar furrows like those of Amphi- 
lichas, certain specimens have the composite lateral lobes indented or 
even divided, as in some specimens of Oncholichas. There is usually 
a faint depression crossing each lateral lobe from the middle of the 
inner side to the palpebral lobe, and in some young specimens this is a 
distinct furrow, as in the specimen from Stanbridge, figured b\- Billings. 
The eyes are very large and prominent, situated close to the furrows. 

Horizon and Locality: — This species was first described from the 
conglomerates of division P at Cow Head, Nfld., and later reported by 
Billings as abundant on lot 20, range 6 of Stanbridge, Quebec. Schu- 
chert and Dunbar found it to be common in pebbles of the Cow Head 
conglomerate at Lower Head, Nfld. 



128 bulletin: museum of comparative zoology. 

Platylichas inconsuetus, sp. nov. 
Plate 6, fig. 12. 

Cranidium (only portion known) large, convex, pentamerously lobed, 
the anterior lateral lobes standing higher than the median or middle 
laterals. The anterior furrows extend back to the occipital furrow, 
being nearest together a short distance in front of it, where they join 
the third lateral furrows, which in turn, circling the back of the ante- 
rior lateral lobes, run forward to the dorsal furrows, which they reach 
in front of the eyes. Outside the anterior lateral lobes is a pair of 
smaller, but convex and prominent lobes, which are believed to be a 
combination of the middle laterals with the lobes of the fixed cheeks, 
and outside them, at a lower level, are the palpebral lobes, poorly pre- 
served on both sides. Very large occipital lobes are present, situated 
largely back of the outer lobes. The occipital furrow is broad and 
deep, and the neck-ring broad. The facial suture cuts the posterior 
margin inside the genal angle. 

Measurements: — The specimen is 30 mm. long, about 41 mm. wide 
between the eye-lobes, and about 47 mm. wide at the fixed cheeks. 
The convexity is about 15 mm. 

Horizon and Locality: — The type (M. C. Z. 1,728) was collected by 
the writer from the Glens Falls limestone (basal Trenton) just above 
the bridge at the falls of Sprakers Creek, one mile south of Sprakers, 
N. Y. 

Hemiarges bartoni, sp. nov. 
Plate 8, fig. 10. 

The genus Hemiarges was erected by Gurich (Neues jahrb. beil. bd., 
1901, 14, p. 526) for lichads of the type of Arges icesenhergensis Schmidt 
with two pairs of bicomposite lateral lobes on the glabella. 

The cranidium here referred to this genus is small, elevated, and 
spinose. The median lobe of the glabella is narrow, highest at the 
front, and covered with spines and tubercles, five of which are more 
conspicuous then the remainder. The anterior lateral lobes are con- 
spicuous mounds, each with a pair of spines. The posterior lateral 
lobes are somewhat triangular, becoming inflated away from the axial 
region, and covered with small pustules. The palpebral lobes are well 
back and distant from the axis. 

This species resembles the type of the genus, but is much more 



RAYMOND: ORDOVICIAN TRILOBITES. 129 

elevated and spinose. The median lobe is narrower and more spinose 
than that of Hemiarges paidiamis (Clarke) and the greatest affinity 
seems to be with H. tube mil at us (Weller) from the Black River in 
New Jersey (Pal. X. J., 1903, 3, 199, pi. 15, fig. 11-13). From that 
species it appears to differ in ha\ing larger and more regularly placed 
spines. 

Measurements: — Length of cranidiimi, 6 mm., width at palpebral 
lobes, 8.75 mm. 

Horizon and Locality: — The single specimen (JSI. C. Z. 1,755) was 
collected in the Kimmswick limest one at Mincke, Mo., by Dr. D. C. 
Barton. 

Odontopleuridae Burmeister. 

Onychaspis, gen. now 

When revising the genera of the Odontopleuridae recently (Ottawa 
nat., 1916, 29, p. 135) 1 did not foresee the almost immediate need 
which has arisen for a name for odontopleurids of the same type as 
Ceratocephala, but in which the free cheeks are not fused to the 
cranidium. That a species of this type should be found in the Ordovi- 
cian is not at all surprising, since the true C'eratocephalae are all 
Silurian and were probably preceded by species in which the cheeks 
were not anchylosed. T\-pe: — Onchaspis confraga, sp. nov. 

Onchaspis confraga, sp. nov. 

Plate 8, fig. 13. 

Only the cranidium and a free cheek of this species have been found. 
They indicate a trilobite of small size with a cephalon of the same 
general pattern as Ceratocephala, but with separable free cheeks. 
There are no dorsal furrows, but the glabella is roughly blocked off 
from the low, convex, fixed cheeks by the glabellar furrows, two pairs 
of which are short and deeply impressed, placed diagonally to the axis, 
while the first pair is represented merely by a pair of pits very close to 
the anterior end of the glabella. The glabella thus roughly limited is 
somewhat rectangular, with lateral projections, narrow, and not 
greatly elevated. The palpebral lobes are damaged, but the eyes 
seem to have stood about midway in the head and not so far forward 
as in Ceratocephala. The neck-ring bears a median tubercle and a 
pair of large spines extending upward and backward. They are 



130 bulletin: museum of comparative zoology. 

longer and more like those of Ceratocephala than would be indicated 
by the figure on Plate 8. On the glabella and cheeks there are a few- 
tubercles of various sizes and, judging from the bases, there were two 
rather conspicuous spines at about the center of the glabella. The 
free cheek is bordered on the outer margin with short stout spines 
extended in an horizontal plane. 

Measureyncnts: — The cranidium, without the spines, is 5.5 mm. 
long; and the glabella is 2.25 mm. wide. 

1 do not know any species with which this can profitably be com- 
pared. The only species in the Chazy, Odonioplcura narrawayi 
Raymond, has two divergent spines on the occipital ring, but has a 
quite different type of glabella. 

Horizon and Locality: — A very rare trilobite at the top of the 
Holston at the Thomas farm, three miles northeast of Blacksburg, Va. 
Holotype (M. C. Z. 1,613). 

Glaphurus decipiens, sp. nov. 
Plate 8, fig. 20. 

Cephalon short, convex, with the glabella rising high above the 
cheeks. Glabella ovate, entirely encircled by narrow but deep dorsal 
furrows. The only glabellar furrows shown by most specimens are the 
posterior ones, which are represented by a pair of deep pits. Occa- 
sional specimens show the first and second pairs of furrows very faintly. 
The eyes are small, situated close to the dorsal furrows and about half 
way to the front of the head. The facial suture cuts the genal angle, 
runs forward and inward to the eye, and then downward and outward 
to the anterior lateral margin. In front of the glabella is a narrow 
furrow and an equally narrow convex rim. The whole surface is 
covered with irregularly dispersed pustules, but no spines are pre- 
served, if any were ever present. 

No parts of the thorax or pygidium have been found. 

Measurements: — The largest cranidium from the Mingan Islands 
is 11 mm. long, and 17 mm. wide. The glabella is 8.25 mm. long, 
(without occipital segment) and 9 mm. wide at the base. The 
cranidium from the Catawba Valley is 8 mm. long; the glabella 6 mm. 
long, and 6.5 mm. wide at the base. 

This species differs from the Glaphuriis piistulatus (Walcott) of the 
Champlain Valley in having only the posterior glabellar furrows well 
developed and apparently in lacking spines and having a much nar- 



RAYMOND: ORDOVICIAN TRILOBITES. 131 

rower border in front of the glabella. On the last two points 1 am not 
absolutely certain as these apparent differences may possibly be due to 
the state of preservation. The pustules are also less regularly ar- 
ranged on the glabella of this species than on that previously described. 
Horizon and Locality: — Four cranidia were collected by Professor 
Twenhofel in zone Ag on Bald Island, Mingan Islands, and I obtained a 
cranidium from the Lower Lenoir at Bluff City, Tenn., and another 
from the Holston limestone in the Catawba Valley, north of Salem, 
Va. The holotype is from the Mingan Islands and is in the Yale 
University Museum. 

AciDiPHORUS, gen. nov. 

This genus includes two species of trilobites which are known 
chiefly from the pygidia, hence its place in the classification is doubtful. 
They are small and the axial lobe of the pygidium extends across the 
margin and is prolonged into a conical spine from two to three times as 
long as the shield. 

Genotype: — Acidiphonis spinifer, sp. nov. 

This genus differs from Goniurus (Bull. 1, Victoria mem. mus., 
1913, p. 65) in that the terminal spine is a prolongation of the axial 
lobe and margin of the pygidium, instead of the latter alone. It is 
not probable that it belongs to any of the established families. 



ACIDIPHORUS SPINIFER, sp. nOV. 

Plate 8, fig. 15, 17. 

Pygidium short, narrow, very convex. The axial lobe, instead of 
having its axis in a plane parallel to that of the margin, as in most 
trilobites, slopes downward and backward, and continues across the 
margin to fonn a spine about twice as long as the shield proper. This 
spine is ornamented with raised longitudinal lines which give it a some- 
what fluted appearance. The anterior end of the axial lobe has five 
rings, and an ornamentation which suggests V-shaped scales. 

The pleural lobes are narrow, steep and somewhat concave. Each 
has one furrowed rib beside the anterior half-rib. 

Horizon and Locality: — Schuchert and Twenhofel collected a pygi- 
dium at their locality 3100-8, zone 11, Point Rich, another at locality 
3100-9, zone 11, and a third, the holotype, in the Leperditia bed at 
Table Head, Nfld. The type is in the Yale University Museum. 



132 bulletin: museum of comparative zoology. 

AciDiPHORUs scoRPiONis, sp. nov. 
Plate 8, fig. 16. 

This species differs from A. spinifer in having a pygidium ^\^th a 
somewhat wider axial lobe which has no rings except the one at the 
anterior end. The outline, disregarding the terminal spine, is less 
triangular, and the pleural lobes less steep. 

Measurements:— T\ie holotype (M. C. Z. 1,756) has the main shield 
of the pygidium 2.25 mm. long, and the spine extends 5.25 mm. beyond 
the margin, the width is 3.00 mm., and the axial lobe is 1.50 mm. 
wide at the front. 

On the same fragment of rock with two pygidia of this sort there are 
two cranidia of Bathyurus hreviceps Billings (Pal. foss. Canada, 1865, 1, 
p. 262, fig. 346), as well as specimens of Remopleurides affinis Billings 
and Arthrorhachis galba (Billings). It may be that this pygidium is 
that of '' Bathi/urus" hreviceps, in which case the specific name scor- 
pionis must be given up, but the generic name Acidiphorus may be 
retained, since no known genus has such a combination of cephalon 
and pygidium. 

Bathyurus hreviceps has pre\iously been known only from cranidia 
found in di\'ision N at Table Head, Nfld. The original specimens and 
those found at Mystic are small, evenly convex, and about the propei* 
size and shape to associate with the pygidia already described. The 
glabella is moderately convex and smooth, without furrows, and the 
cheeks broad, gently convex, united in front of the glabella by a very 
narrow ridge. The eyes are small, situated far back and far apart. 
There is a narrow upturned frontal border. 

Horizon and Loccdify: — Two specimens of the pygidium were found 
in a boulder in a conglomerate on lot 22, concession VI, of Stanbridge, 
Que., about two miles northeast of Mystic Station. The boulder 
contained numerous trilobites of Normanskill types. 



PROPARIA Beecher. 

Encrinuridae Angelin. 

Encrinurus nodosarius, sp. nov. 

Plate 8, fig. 14. 

Like many species of the genus, this one is known from the pygidium 
only. That shield is of small size, slightly broader than long, and the 
first four pairs of ribs cross the border and end in short rounded spines. 



RAYMOND: ORDOVICIAN TRILOBITES. 133 

The axial lobe has ten distinct rings which run entirely across it, and 
behind the distinct rings several more which are so close together 
that they cannot be counted. The pleural lobes have six pairs of ribs. 
The first four pairs cross the border and end in short rounded spines 
whereas the last two pairs turn back parallel to the posterior end of the 
axial lobe and their outer ends do not cross the border. The rings 
and ribs are both minutely pustulose, but the pustules are so small 
that they are only seen when the specimen is held at certain angles. 

Mrasuremrnis: — Length of pygidium 3.5 mm., width 4.25 mm. 
^^ idth axial lobe at front 1.5 mm. 

The older Ordovician species of Encrinurus are E. rarus (\\ alcott), 
E. trcntonensis ^^'alcott, E. tuhcrculosus Collie, E. I'annulus Clarke, 
E. rigilaiis (Hall), and E. varicosfatus Walcott. The name of the last 
species was unfortunately misprinted raricostafus by Clarke and so 
continued in Bassler's bibliography. 

Encrinurus rarus, originally described as a Ceraurus, is known only 
from a fragmentar\' cephalon, but is probably the same species as 
E. vannnhts Clarke. E. vannulus and E. raricostafus both agree with 
the form just descril)ed in having only six pairs of pleural ribs. Neither 
of these species is, however, tuberculated. E. rannidus has, moreover, 
only six to seven distinct rings on the axial lobe whereas E. nodosarius 
has ten and only three pairs of ribs have free endings. E. varicosfatus 
is probably most closely allied to E. nodosarius, but besides lacking 
pustules on the surface, five pairs of the ribs end in spines, and the 
ribs are much broader than in our species. Encrinurus ric/ihnis and 
E. trentoncnsis both have nine pairs of ribs on the pleural lobes, and 
E. tuherculosus has eight pairs, and the great number of twenty-five 
distinct rings on the axial lobe. 

Horizon and Locality: — The single .specimen (M. C. Z. I,bt4) on 
which this species is founded was found in the Lenoir, about six miles 
southeast of Knox\ille, Tenn., on the same piece of limestone as a 
specimen of PJiouierops canadensis. 

Cybeloides iowensis Slocom. 
Plate 9, fig. 8. 

Cijbeloides iowensis Slocom, Bull. Field mus. nat. hist. Geol. ser., 191.3, 4, no. 3, 
p. 64, pi. 16, fig. 1-4. Ann. rept. Geol. surv. Iowa, 1916, 15, p. 213, pi. 
17, fig. 1-4. 
The pygidium of the type of this species was so poorly preserved 

that it Avas neither figured nor described in detail. Four pygidia were 



134 bulletin: museum of compakative zoology. 

obtained by the writer from the Maquoketa, one from the typical 
locaHty for the species, Elgin, Iowa, and three along a stream four 
miles west of Clermont. 

The pygidium is narrow, highly \'aulted, subtriangular, acutely 
rounded behind. The axial lobe is about one half the total width, and 
tapers regularly backward, extending nearly to the posterior end, 
where it descends gradually to the general surface. It is crossed by 
but one complete ring, that at the anterior end, but is indented at the 
sides by about fourteen pairs of oblique pits, and has on the top six 
pairs of small sharp tubercles. 

The ring at the anterior end of the axial lobe bifurcates on the 
pleural lobes producing on either side a pair of elongate ribs which 
curve around parallel to the margin, closely approaching the axial 
lobe at its posterior end. The outer rib of each pair is marginal, and 
the inner one parallels it. Between this latter ridge and the axial lobe 
there is on either side a space covered by less conspicuous ribs. The 
pair nearest the axial lobe are short, start back of the middle, and ex- 
tend to the posterior end, separated from the axial lobe b\' a very 
narrow furrow. Just outside these lie another pair which extend 
nearly the whole length of the pygidium about parallel to the axis, 
but deflected somewhat where they embrace the ribs just mentioned. 
Another very faint rib intervenes on either side between the long one 
iand the inner of the marginal pair. 

Rounded tubercles are scattered sparsely over the surface, particu- 
larly along the ribs. 

Measurements: — The pygidium described and figured is 7 mm. long, 
6 mm. wide; and the axial lobe is 2.75 mm. wide at the anterior end. 

The p\gidium differs from that of other known species of this genus 
in that none of the pleural ribs ends in a free spine, and the lateral 
lobes have fewer ribs. The nature of the pygidium shows conclusively 
that Ci/beloides iowensis is quite distinct from C. winchelli (Clarke). 

Cybeloides, sp. ind. 

A single glabella of a Cybeloides was found at the base of the reef 
in the Holston on the Hoge farm, Bland Co., Va. It is too imperfect 
for specific identification, but is sufficient to indicate the presence of 
this genus in the Holston. This glabella resembles that of Cybeloides 
prima (Raymond) of the Chazy in ha\ing three pairs of glabellar 
furrows developed as pits along the sides, but the surface appears to 
be less pustulose. The single glabella is 3.5 mm. long. 



RAYMOND: ORDOVICIAJV TRILOBITES. 135 



Cybele MIR a (Billings). 

Encrinurus 7nirus Billings, Pal. foss. Canada, 1865, 1, p. 292, fig. 282. 
Cryptonymus mirus Vogdes, Mon. genus Zethus, 1878, p. 34. 
Cijhele ynirus Clarke, Geol. Minn., 1897, 3, pt. 2, p. 743. 

Specimens collected by Schuchert and Twenhofel add a little to 
what has previously been known of this species. The cephalon has a 
pair of rather long, thick, and strongly divergent genal spines, but the 
presence of three pairs of straight lateral furrows and no longitudinal 
furrows on the glabella show that this is a true Cybele and not a 
Cybeloides. Both the cranidia show the median furrow in the frontal 
lobe and the \ery curious branching of the anterior lateral glabellar 
furrows mentioned by Billings. The p\'gidium has four pairs of 
double ribs, the anterior half of each rib being much higher and wider 
than the other. This produces an appearance of an alternation in 
size of ribs which does not seem to occur in Cybeloides, but is to be 
observed in the Russian species of Cybele. All of the rings on the 
axial lobe seem to run entirely across, which is unusual in Cybele, and 
unknown in Cybeloides. 

Measurements: — The largest glabella is 6 mm. long, 4 mm. wide at 
the back and 6 mm. wide at the front. A small cephalon is 4 mm. long, 
and 10 mm. wide, not including the genal spines. A pygidium is 
10 mm. long, and 11 mm. wide. 

Horizon and Localiti/: — Billings reported this species from horizon 
N, Table Head and Pistolet Bay, and P, Portland Creek, Nfld. Pro- 
fessors Schuchert and Twenhofel obtained specimens in their horizons 
Ni and No at Table Head. Professor Hyatt collected a rather poorly 
preserved thorax, retaining parts of fifteen segments, and a v^ery poorly 
preserved pygidium, on the western side of Gargamella Cove, Nfld. 
All are from the horizon of the Normanskill. 



EcTENONOTUS Raymond. 
Edenonotus Raymond, Bull. M. C. Z., 1920, 64, p. 279. 

Among the anomalous trilobites described by Billings was one which 
had a glabella \ery like that of a Pliomerops, and a pygidium strongly 
suggestive of Encrinurus. Although no entire specimens have been 
reported the "glabella and pygidium were found in about equal 
numbers together, and in great abundance. Out of one small piece 
of rock scarcely a yard in length, there were taken twenty-seven speci- 



136 bulletin: museum of comparative zoology. 

mens of the glabella, and twent;s-i'our of the pygidium. In this mass 
of rock there was no other head to Avhich the pygidium could be 
referred, nor any other pygidium to which the head could possibly 
have belonged." 

The pygidium is distinctly Encrinurus-like in its elongate narrow 
form, very long axial lobe with numerous rings, and particularly 
in the way in which the posterior ribs on the pleural lobes curve back 
around the end of the axial lobe. The pygidium shows some differ- 
ences from both Encrinurus and C\bele, but the;\' are of a relatively 
minor character, and if it were not for the associated cranidium, 
the species would undoubtedly be admitted to the genus Encrinurus. 

Although the cephalon is Pliomerops-like, certain encrinurid char- 
acteristics maj^ be seen in it, particularly when compared with Cybele. 
The form of the glabella and position of the glabellar furrows is similar 
to what is seen in Cybele bellaivla (Dalman) (Schmidt, Mem. Acad, 
imp. sci. St. Petersburg, 1881, ser. 7, 30, p. 203, pi. 13, fig. 9) and the 
glabella does not expand toward the front as in Pliomerops. The 
most important point, however, is that the eye is not situated close 
to the glabella as in Pliomerops. The eye is not shown in any of the 
specimens but enough of the fixed cheek is preserved to indicate that, 
whether the eye is ultimately found to be far forward, as in Encrinu- 
rus and some species of Cybele, or far back as in other species of that 
genus, it must at least be placed at some distance from the glabella 
and thus be encrinurid in position. 

Billings made the cranidium the holot\pe of the species Amphion- 
westoni, so that in case it should prove that the cranidium and pygid- 
ium do not belong together, the pygidium will belong to an unnamed 
species. 1 propose to designate the specimen from Newfoundland 
retaining the thorax and pygidium as the holotype of the genus, in 
order that there may be in the future no uncertainty as to how the 
names should apply. 

Encrinuridae with pygidia whose simple pleural ribs do not end in 
spines, and whose glabellae have a pair of furrows which emerge on 
the front instead of the lateral border. 

Type: — Edenonotus westoni (Billings). 

Another species is E. odocostatus (Reed) from Glensaul district in 
Ireland. 



RAYMOND: ORDOVICIAN TRILOBITES. 137 

EcTENONOTUS WESTONi (Billings). 
Amphion tcestoni Billings, Pal. foss. Canada, 1865, 1, p. 321, fig. 307a, b. 

The l)est specimen from Newfoundland has twelve segments of the 
thorax and the pygidium preserved. The specimen is long and narrow, 
and does not taper rapidly. The axial lobe of the thorax makes up 
about one third the width and is only moderately elevated. The 
pleural lobes are rounded and turned down abruptl\- at the sides. 
Each pleuron is divided by a shallow narrow furrow into an anterior 
and posterior portion, the latter about twice as broad and somewhat 
higher than the former. Near the dorsal furrow there is a pair of low 
mounds on the proximal ends of both adjoining pleural rib and axial 
ring. 

The axial lobe of the pygidium is long and narrow, with al)out 
twenty-one rings. The pleural lobes slope away to the borders and 
are crossed by fen pairs of simple ribs, the last four of which turn 
back approximately parallel to the axial lobe and behind it the cor- 
responding ones on opposite sides turn toward each other, so that they 
meet on the posterior border. 

Measurements: — Billings states that the largest glabella in his col- 
lection is 10 lines (20 mm.) long, and 7 lines (14 mm.) wide. The 
pygidium he figured is 26 mm. long, and 26 mm. wide at the front, the 
axial lobe being 8.5 mm. wide at the anterior end. 

The specimen from Newfoundland retaining thorax and pxgidium is 
36 mm. long, the pygidium 15 mm. long. 

Horizon and Locality: — Billings's original specimens were from the 
"Quebec group" at Stanbridge, Que., where it was found associated 
with several other curious trilobites, a few of which have since been 
found in strata of the tvpical Chazy of the Champlain \'alley, l)ut most 
of which are still little knoAvn. It is fairly common in boulders in a 
conglomerate two miles north of Mystic, Que. 

The specimens from Newfoundland were found by Professors Schu- 
chert and Twenhofel at Point Rich in their zone 11 (3100-8), associ- 
ated with Pliomerops barrandei, Bathyurelhis validus, lUacnusf rater mis, 
and other trilobites. More recently Professors Schuchert and Dunbar 
have collected it on the south shore of East Bay near Port au Port, 
and at Twohill Point, Port Saunders, Nfld. All specimens are pygidia 
and fragments of the thorax. The horizon is Normanskill. 



138 bulletin: museum of comparative zoology. 



EcTENONOTUs ocTOCOSTATUs (Reed). 

PUomera pseudoartictdata Reed (non Portlock), Quart, journ. Geol. soc. Lon- 
don, 1910, 66, p. 276, pi. 22, fig. 5, 6. 
Encrinurus octocostatus Reed, Ibidem, p. 277, pi. 32, fig. 4a, b. 
Encrinurus sp. Reed, Ibidem, 1909, 65, p. 147. 

Reed, in his study of the fragmentary trilol^ites of the Glensaul 
district (Ireland) was confronted with the same curious association of a 
Pliomera-like cephalon and an Encrinurus-like pygidium that Billings 
had experienced in the case of Amphion westoni. He compared the 
cranidium with that of Amphion westoni, but because of another pygid- 
ium, assigned his specimens to PUomera pseudoarticulata (Portlock). 
This latter species is known from pygidia only, and both cranidia and 
pygidia cited above being so like the American Ectenonotus westoni, 
it seems probable that they belong together. 

The cranidium assigned to E. octocostatus is wider at the genal angles 
than E. westoni, but the glabellae of the two are alike in shape and 
position of furrows. The position of the eye is not shown. The 
pygidium has eight pairs of ribs on the pleural lobes, the last pairs 
turning backward and uniting with the axial lobe, as do those of E. 
westoni. The latter, howe\-er, has two or three more pairs of ribs. 

Horizon and Locality: — This species was found in a calcareous ash 
on the Glensaul River, near Garranangerra, County Galway, Ireland. 



Calymenidae Milne-Edwards. 

Calymene, sp. ind. 

The presence of this genus in the upper layers of the Holston at 
the prolific locality northeast of Blacksburg is of considerable interest, 
but the three pygidia and one glabella collected are not sufficient on 
which to base a species in so difficult a genus. All the fragments 
indicate a trilobite of very small size. The glabella is finely tuber- 
culated and shows three pairs of furrows, the first pair very near the 
front, short, and faint. The others are deeply impressed and bound 
glabellar lobes of the form usual in the genus. The best preserxed 
pygidium shows four rings on the axial lobe and four pairs of ribs on 
the pleural lobes, each rib with a narrow impressed line extending the 
full length. The ribs extend quite to the margin and the whole sur- 
face is tuberculated. Except for their small size, these fragments 



RAYMOND: ORDOVICIAN TRILOBITES. 139 

show, SO far as the^^ are preserved, the specific characteristics of the 
common Calymene senaria. 

Measuremenis: — The single glabella is 5 mm. long, 3.5 mm. wide 
at the front, and about 4.5 mm. wide at the basal lobes. The best 
pygidium is 3.25 mm. long, and 4 mm. wide. The other two pygidia 
are each 4 mm. long. 

Horizon and Locality: — So far found only in the top of the Holston, 
three miles northeast of Blacksburg, Va. 

Cheiruridae Salter. 
Ceraurus granulosus Raymond and Barton. 

Ceraurus pompilius Raymond (non Billings), Ann. Carnegie mus., 1905, 3, 
p. 365 {non fig. 6), pi. 14, fig. 14. 7th rept. Vermont state geol., 1910, 
p. 240, pi. 36, fig. 14. 

Ceraurus granulosus Raymond and Barton, Bull. M. C. Z., 1913, 54, p. 536. 

A Ceraurus which seems to belong to the above species is common in 
the upper part of the Holston at the well-known locality three miles 
northeast of Blacksburg, but all the specimens we obtained were very 
fragmentary". 

The glabella of the Virginian specimens is nearly parallel-sided, the 
basal lobes are more or less quadrangular, and the surface is granulose 
rather than pustulose. All these characteristics are like those of C. 
granulosus. The genal spines have not been seen. Nearly all the 
glabellae are exfoliated, in which condition they of course suggest 
Ceraurinus. 

The associated hypostoma is of the usual form for the genus, narrow, 
strongly convex, and moderately pustulose. 

No part of the thorax has been seen and only one pygidium. That 
is short and wide, the great spines both broken, but strongly divergent 
and between the great spines the posterior margin is angulated by two 
pairs of very short blunt spines. 

Measurements: — A large cranidium is 6.5 mm. long; and the 
glabella 4.5 mm. wide at the back and 5 mm. wide at the front. x\n 
hypostoma is 5.5 mm. long, 5 mm. wide; and the body is 3.25 mm. wide. 

Horizon and Locality: — This species is foimd near the top of the 
Middle Chazy and at the base of the Upper Chazy on Valcour Island, 
N. Y., and at the top of the Holston at the Thomas farm, three miles 
northeast of Blacksburg, Va. A single glabella was found in the 
Liberty Hall at Lexington, Va., and another in the Lower Lenoir at 
Bluff Citv, Tenn. 



140 bulletin: museum of comparative zoology. 



Ceraurus HUDSON I Raymond. 

Ceraurus hudsoni Raymond, Ann. Carnegie mus., 1905, 3, p. 367, pi. 14, fig. 15. 
7th rept. Vermont state geol., 1910, p. 240, pi. 36, fig. 15. Raymond 
and Barton, Bull. M. C. Z., 1913, 54, p. 535. 

A well-preser\e(l cranidium indicates the presence of this species in 
the Ottosee. The specimen agrees with C. hudsoni rather than C. 
'pleurexanthemus Green in having a more rapidly expanding glabella, 
and in lacking any arrangement of pustules in rows pa rallelto the axis. 
The genal spines flare widely as in both the species mentioned. 

Measure mints: — The cranidium is 14 mm. long, 32 mm. wide at 
the nuchal furrow, not including the genal spines. The glabella is 
10.5 mm. wide at the frontal lobes, 8 mm. wide at the basal lobes, and 
is 10 mm. long, exclusive of the nuchal segment. 

Horizon and Locality: — This species has previously been found 
only at the top of the middle ('hazy on Valcour Island, X. Y. 

The specimen mentioned above was found in the Ottosee near 
Tilsons Gap, Bland Co., Va. 

A Ceraurus which seems to belong to this species has been found in 
the Holston on the Hoge farm, Bland Co., Va., and in the Catawba 
Valley, north of Salem, Va., also in the middle Ottosee, seven miles 
north of Mendota, Va. The glabella is strongly pustulose and expands 
toward the front. The specimens are, howe\er, too few and frag- 
mentary to make the identification certain. 



Ceraurus angustus, sp. nov. 
Plate 8, fig. 22. 

Cephalon long and narrow for the genus, highly vaulted, with 
steeply sloping cheeks. A second specimen indicates that the genal 
angles were draAvn out into broad spines, which are, however, absent 
from the tA'pe. 

As viewed from above, the glabella occupies about one third the 
width, is moderately con^'ex, smoothl\- rounded in front, the sides 
parallel. Glabellar furrows as usual in Ceraurus, the last pair some- 
what oblique, so that the basal lobes are not exactly rectangular. The 
surface is covered Avith small sharp pustules and granules. 

Cheeks small, covered with small circular pits with intervening 
anastamosing ridges, on which are small, rounded granules. Eyes 
large, opposite the second and third glabellar lobes, and nearer the 



I 



RAYMOND: ORDOYICIAX TRILOBITES. 141 

dorsal than the nuchal furrow. Nuchal segment narrow, with 
granulose surface. 

Measurements: — The holot\pe (M. C. Z. 1,724) is 12 mm. long, and 
about 22 mm. wide at genal angles (without spines). The glabella is 
9 mm. long, 8.25 mm. wide at the frontal, and 8 mm. wide at the 
basal lobes. Width at palpebral lobes about 15 mm. 

This is a remarkably narrow Ceraurus, and were it not for the shape 
of the glabella, would suggest a Cyrtometopus. This characteristic 
readily distinguishes it from other species. The glabella alone might 
be confused with that of C. granulosus, ha\'ing the same shape and 
ornamentation, but it lacks the square basal lobes of that species. 
Ceraurus ingricus Schmidt and C. glaber Angeliu are similar narrow 
forms in northern Europe. 

Horizon and Locality: — Dr. E. W. Shuler collected three cranidia 
of this species from the Ottosee at Tilsons Gap, Bland Co., Va. 



Ceraurus tenuicornis, sp. nov. 
Plate 8, fig. 23. 

This species is based on a single well-preserved pygidium found at 
about the middle of the Athens. It is remarkable for the reduction 
of all parts except the great spines, the posterior margin between 
them being almost straight. The anterior segment of the pygidium is 
almost entirely free from it and is a short narrow segment with short 
slender pleural spines. The axial lobe behind this has three rings, the 
first connecting the great spines, and the other two in the very short 
area behind. The third one is so reduced as to be a mere pustule. 
The great spines are long, slender and curve slightly outward near the 
tips. The surface is covered with fine granulations. 

Measurements: — Length of central portion, 1.5 mm., length over 
all, 10 mm. 

It is barely possible that this pygidium ma\' prove to belong to 
Ceraurus granulosus, but it is not in agreement with the pygidium 
found near Blacksburg associated with glabella referred to that species. 
The ornamentation, if the same on the cephalon as on the pygidium, 
would be even more delicate in the cephalon of this species than in 
C. granulosus. 

This specimen exhibits a greater reduction of the axial part of the 
pygidium than in any other known species of Ceraurus, and this 
tendency is here carried almost to the same extreme as in the Deiphon 



142 bulletin: museum of comparative zoology. 

of the Silurian. It is of interest to note that the culmination of this 
tendency was reached at approximately the same time (Upper Chazy) 
as the greatest development of the opposite type of pygidium, as seen 
in Ceraums ruedemanni Raymond from New York. 

Horizon and Locality: — This species is so far known only from a 
single pygidium (M. C. Z. 1,664) found beside the railroad track two 
miles north of Bullsgap, Tenn., in material brought from the cutting 
one mile south of Otes. The horizon seems to be in the middle of the 
Athens. 



Ceraurus ruedemanni Raymond. 
Plate 9, fig. 1, 

Ceraurus ruedemanni Raymond, Bull. 189, N. Y. state mus., 1916, p. 121, pi 

30, fig. 9-12. 
Undetermined hypostoma Raymond, Ann. Carnegie mus., 1910, 7, pi. 19, 

fig. 22. 

This species was described from fragments collected b\' Dr. Ruede- 
mann. More recently the writer has found at the typical locality an 
incomplete cranidium which is somewhat larger and more perfect than 
the original. It shows that although the eye is large, the palpebral 
lobe is small, and that very strongly defined eye-lines are present. 

Until this trilobite was discovered, Ceraurus scidiger (Eichwald) 
and C. dentaius Raymond and Barton were the species of the genus 
which had produced the largest specimens. Complete specimens 
of the latter, 84 mm. in length on the median line, have been found, 
and the length of C. scuiiger is estimated at 106 mm. Ceraurus 
ruedemanni, however, if it had the same proportions as C. dentaius, 
must have reached a length on the median line of 160 mm., and at 
least 25 mm. should be added for the pygidial spines. Under the 
favorable conditions w^hich existed among the reefs of Stromatocerium 
in the later parts of Chazy time, trilobites appear to have reached 
unusual size. 

Measurements: — The cranidium figured is 46 mm. long, and 73 mm. 
wide at the palpebral lobes. The glabella is 37 mm. long, 38 mm. wide 
at the front, and 35 mm. at the basal lobes. 

Horizon and Locality: — This species has so far been found only in 
the reef at the base of the Upper Chazy in a pasture, three miles east of 
Chazy, N. Y., and at the same horizon at Coopersville, N. Y. 



o 



RAYMOND: ORDOVICIAN TRILOBITES. 14 



• Ceraurinus pompilius (Billings). 

Cheirurus pompilius Billings, Pal. foss. Canada, 1865, 1, p. 181, fig. 162. 
Ceraurinus pompilius Barton, Bull. M. C. Z., 1913, 54, p. 550. Washington 
univ. studies, 1916, 3, pt. 1, no. 1, p. 134. 

The original locality of this species cited by Billings was "South 
side of Large Island, Mingan Islands." Professor Twenhofel collected 
a single imperfect glabella of e.xactly the same size as the type in zone 
As on Bald Island, Mingan. Since it has been shown that the speci- 
mens from Valcour Island, N. Y., which I identified as C. pompilius 
do not belong to it (Bull. M. C. Z., 1913, 54, p. 536), this species is 
unknown outside the typical region. 

Attention should be called to the date of publication of Dr. Barton's 

second paper, which, through no fault of the author, bears the date of 

July, 1915, although it was not actually published till 20 January, 

'191*6, and not distributed, at least in the form of separata, for some 

weeks after that. 

Ceraurinus polydorus (Billings). 

Cheirurus polydorus Billings, Pal. foss. Canada, 1865, 1, p. 286, fig. 274, 
Ceraurinus polydorus Barton, Bull. M. C. Z., 1913, 54, p. 549. Washington 
univ. studies, 1916, 3, pt. 1, no. 1, p. 134. 

One of the specimens from Newfoundland reveals the presence in 
this species of eye-lines, which originate a little in front of the middle of 
the first lateral glabellar lobes, and run backward to the palpebral 
lobes, which are opposite the second pair on the glabella. Otherwise 
the specimens add nothing to what was known from Billings's short 
description. 

Horizon and Locality: — Billings's specimens were from division N, 
Table Head, and division P, Portland Creek. Professors Schuchert 
and Twenhofel collected it only from their zones Ni and N2 at Table 
Head, Nfld. Professor Hyatt collected a rather good cranidium from 
the conglomerates at Cow Head, Nfld. 

Kawina vulcanus (Billings). 

Cheirurus vulcanus Billings, Pal. foss. Canada, 1865, 1, p. 284, fig. 271a-c (nan 

p. 324, fig. 310a-c). 
Pseudosphaerexochus vulcanus Raymond, Ann. Carnegie mus., 1905, 3, p, 367, 

pi. 14, fig. 16, p. 368, fig. 10. 7th rept. Vermont state geol., 1910, p. 241, 

pi. 36, fig. 16. Grabau and Shimer, N. A. index fossils, 1910, 2, p. 320, 

fig. 1634d. 



144 bulletin: museum of comparative zoology. 

Cheirurus prolificus Billings, Pal. foss. Canada, 1865, 1, p. 325, fig. 311, 312. 
Ceraurus {Psevdos-phaerexochus) -prolificus Clarke, Geol. Minn., 1897, 3, pt. 2, 

p. 738. 
Kaivina vulcamis Barton, Washington univ. studies, 1916, 3, pt. 1, no. 1, p. 117, 

fig. 9. 

Professor Hyatt collected a glabella of this species at the typical 
locality, Cow Head, Nfld. Billings cited it under the names Cheirurus 
vulcanus and C. prolificus from Stanbridge, Que., and from the Upper 
Chazy at Montreal. Mrs. Eleanor M. Hudson later found a single 
incomplete cephalon, which 1 figured, in the lower part of the Upper 
Chazy on Valajur Island, N. Y. Professor Twenhofel collected a single 
small glabella in zone A5, Upper Chazy, on Bald Island, Mingan 
Islands. 

Professors Schuchert and Dunbar collected a large number of cran- 
idia and cephala of Cheirurus prolificus and a smaller number which 
can be referred to C. vulcanus from the type-locality. After going over 
them rather carefulh* it appears probable that the specimens called 
C. prolificus are the young of C. vulcanus. The only difference notcfl 
by Billings was that in C. vulcanus the eye was opposite the anterior 
end of the last glabellar lobe, whereas in C. prolificus it was opposite 
the second lobes. As can be seen by inspecting Billings's figures there 
was only a very slight difference in position of the eyes of the types, and 
one would expect to find the eyes slightly farther forward in young 
than in adults. Moreover, 1 find there is a slight variation in the 
position of the eyes among specimens of C. prolificus, they being 
farther back in some than in others. The specimens called C. pro- 
lificus are generally smoother than the typical C. vulcanus, but that 
appearance is due in part to the state of preservation. 

One small fragment shows the last four segments of the thorax. 
The axial lobe is wide, moderately convex. The pleural lobes are flat 
and not much deflected at the sides, but the ends of each segment 
curve backward in flat spines. Each pleural portion of a segment has 
a narrow impressed line running diagonally across it. A single small 
pygidium presents the same characteristics as the one figured by 
Billings, except that the posterior end of the axial lobe is more blunt. 

K A WIN A sp. 

Pliomera aff. fischeri (Eichwald). Reed, Quart, journ. Geol. soc. London, 
1909, 65, p. 144, pi. 6, fig. 4. 

The presence of a Kawina closely related to K. vulcanus (Billings) in 
Ireland is indicated by the excellent figure published by Reed. As in 



RAYMOND: ORDOVICIAN TRILOBITES. 145 

the Canadian species there are three pairs of broad blunt ribs, a wide 
V-shaped axial lobe wdth four rings and a triangular terminal piece. 
It seems, however, to be wider, and the surface, so far as one can 
judge from the description and figure, is smooth. 

Horizon and Locality: — This species was found in a limestone 
breccia, one mile southAvest of the GortbunacuUin farm, in the Tour- 
makeady district, County Mayo, Ireland. 

Kawina trentonensis (Clarke). 

Pseudosphaerexochus trentonensis Clarke, Geol. Minn., 1897, 3, pt. 2, p. 734, 
fig. 53, 54. Weller, Geol. surv. New Jersey. Pal., 1903, 3, p. 205, pi. 
15, fig. 24, 25. 

In the absence of any specimens retaining the free cheeks. Barton 
(Washington univ. studies, 1916, 3, pt. 1, no. 1) was unable to place 
this species generically. The Walcott collection from Trenton Falls 
contains two cranidia which retain parts of the fixed cheeks, and, 
although neither is satisfactorily preserved, they show that the eyes 
were small, located close to the glabella opposite the second pair of 
lobes, and that the fixed cheeks were covered with pits surrounded by 
inosculating ridges dotted with small pustules. The cheeks slope 
abruptly downward from the highly vaulted glabella, and the pos- 
terior course of the facial suture is first outward, then slightly foi'ward, 
turning backward in a broad arc to the genal angle. 

The eyes are nearer the glabella, and the posterior branch of the 
facial suture reaches the posterior .margin farther back than in Pseu- 
dosphaerexochus, so that the agreement with Kawina is much more 
complete. 

Measurements: — A large glabella {plus the occipital ring) is 25 mm. 
long and 24.5 mm. wide at the base. A smaller one is 13 mm. long 
and 13 mm. wide at the base. 

Horizon and Locality: — This species, the largest of the genus, is the 
sole one to survive so late as the Trenton. It has been found in the 
Trenton only at Trenton Falls, X. Y., but is also known from the 
Black River at Jacksonburg, X. J. 

XlESZKOWSKIA EXCELSU.S, Sp. nov. 

Plate 10, fig. 8. 

A large Nieszkowskia, with a very convex, highly vaulted cephalon. 
Glabella very convex, semioval in outline, with a long spine standing 



146 billetin: museum of compakative zoology. 

erect on the highest point. There are three pairs of glabellar furrows, 
all narrow and shallow. The posterior pair are distinct, originating in 
the dorsal furrows opposite the posterior margin of the eye, and 
running back to the neck-furrow, thus producing a pair of large tri- 
angular basal lobes. The other two pairs are A'ery faint, and extend 
only part way up the sides of the glabella. 

The specimen retains the left free cheek and eye. The eye is situ- 
ated in about the middle of the cheeks and is small, l)ut prominent. 
The facial suture follows the usual course in Xieszkowskia, the pos- 
terior branch cutting the lateral margin some distance in front of the 
genal angle and only a little behind the eye; the anterior branch turns 
forward and reaches the anterior margin near the dorsal furrow. The 
cheeks are marked by a number of large pits and numerous small 
sharp pustules. 

Thorax and pygidium unknown. 

Measurements: — The single half cephalon preserved is 21 mm. long, 
and about 40 mm. wide. 

The only other large Nieszkowskia which has been described in this 
country is N. perforator (Billings) from division N, Table Head, Nfld. 
That species is quite different from the present one, as the spine points 
forward and not upward. N. glaucus (Billings) and N. satyrus 
(Billings) from the "Quebec group" at Stanbridge, Que., have a spine 
on top of the glabella, but in both species the spine is situated farther 
back on the glabella, and is inclined backward instead of forward. 
No European species of Nieszkowskia appears to have a spine on top 
of the glabella. 

Horizon and Locality: — The single specimen was found by Professors 
Schuchert and Twenhofel in their zone 10 at Port au Choix, Nfld., 
where it was associated with PUomerops barrandei, Bathyurellus validus, 
and Illaenvs (Normanskill age). Holotype in the Yale University 
Museum. Plastotype (M. C. Z. 1,757). 

Nieszkowskia perforator (Billings). 

Cheirurus perforator Billings, Pal. foss. Canada, 1865, 1, p. 287, fig. 275. 
Ceraurus {Nieszkoivskia) perforator Clarke, Geol. Minn., 1897, 3, pt. 2, p. 738. 

A small and incomplete glabella which appears to belong to this 
species was found by Professors Schuchert and Twenhofel in their zone 
11 at Point Rich, Nfld. Although much smaller than Billings's speci- 
men from division N, the shape and ornamentation of the glabella and 
the position of the spine and glabellar furrows is the same. In zone 



RAYMOND: ORDOVKIAX TRILOBITES. 147 

11 it is associated with Pliomerops barrandei, Illacuus fraternus, two 
other species of lllaenus, and Acidiphorus. It is thus a Normanskill 
species. 

NiEszKowsKiA, sp. ind. 
Plate 8, fig. 21. 

A specimen of large size is indicated by a single pygidium which 
unfortunately is damaged on all margins. As nearly as can be made 
out, the outer pleural ribs ended in spines, whereas the inner pair of 
ribs were united with the central piece, and the posterior margin of 
this portion was smoothl\' curved. This would produce a type of 
pygidium very unusual in Xieszkowskia, but more nearly like it than 
any other genus of cheirurids. 

The cranidia of several species of Xieszkowskia are known in Amer- 
ica, but only one other pygidium, a small one described by me (Ann. 
Carnegie mus., 1910, 7, p. 76, pi. 18, fig. 13, pi. 19, fig. 20) from the 
Chazy at Chazy, X. Y., has been found. 

This large pygidiimi suggests such a form as Xicszk-ou-skia varlolaris 
(Linnarsson), illustrated so fully by Schmidt (Mem. Acad. imp. sci. 
St. Petersburg, 1881, ser. 7, 30, pi. 9, fig. 6-8). That species was 
supposed by Schmidt to ha\e two pairs of broad spines on the pygidium. 

Measurements: — ■ The pygidium is 15 mm. long, and in its present 
incomplete state, 21 mm. wide. 

Horizon and Locality: — The single specimen (M. C. Z. 1,623) was 
found in the Holston of the Catawba Valley, north of Salem, Va. 

Hadrohybus, gen. nov. 

This genus is proposed for Cheirurinae with very tumid glabella and 
with the vestiges of glabellar furrows represented only by pits, this 
being the principal distinction from Xieszkowskia. Type: — Hadro- 
hybus dunbari, sp. nov. 

Hadrohybus dunbari, sp. nov. 

Plate 9, fig. 5, 6. 

This species is based on two rather incomplete cranidia, one about 
30 mm., the other about 60 mm. long, and thus both of large size for 
members of the family. The glabella is extremely tumid with a 
somewhat compressed elevation near the front. A pair of shallow pits 



148 bulletin: museum of compaeative zoology. 

opposite the posterior part of the palpebral lobes represent the only 
Aestiges of glal)ellar furrows. The fixed cheeks are only partially 
exposed, but appear to have been about as large as those of a Xiesz- 
kowskia. The front of the glabella is surrounded by a moderately 
wide, convex rim, from which it is separated by a narrow furrow. The 
palpebral lobe is large, with a distinctly flattened rim and is situated 
about half way to the front. The eye must have been very large. 

The surface of the fixed cheeks, palpebral lobes, and the rim about 
the glabella is marked by shallow irregular pits and small depressed 
pustules. The surface of the glabella appears to be nearly smooth, 
but under a hand lens shows numerous fine anastomosing lines which 
gi\'e the surface a scale-like appearance. 

This form can only be compared with species of Xieszkowskia, from 
all of Avhich it (lifters in the reduction of the glabellar furrows. 

Measurements: — The smaller cranidium, the holotype, is about 
30 mm. long and 38 mm. wide at the palpel)ral lobes. The highest 
point on the glaliella is 17 mm. above the le\el of the tops of the eyes. 
The larger cranidium is about 60 mm. long, about 7(3 mm. wide at the 
palpebral lobes; and the highest point on the glabella is about 35 mm. 
above the level of the e\'es. A palpebral lobe is 15 mm. long. 

Horizon and Locality: — These fossils were collected by Prof. C. O. 
Dunbar from a pebble in the Cow Head conglomerate on Stearing 
Island, opposite Cow Head, Nfld. In the same pebble were speci- 
mens of Eoharpcs fragilis, Homotclus catadus, lllaenus, sp. and Pli- 
omerops barrandei. The age indicated is therefore Normanskill. 
Cotypes in the Yale Uni\ersity Museum. 



Sphaerocoryphe major Ruedemann. 

Sphaerocoryphe major Ruedemann, Bull. 49, N. Y. state mus., 1901, p. 67, 
pi. 4, fig. 13. 

Since the finding of any of the species described b\' Ruedemann 
from the pebbles of Rysedorph Hill in regularly bedded rocks is 
always worth recording, 1 would note here the discovery of a single 
glabella of this species in the Upper Echinosphaerites zone at Stras- 
burg, Va. The bulbous part of the glabella is 8.5 mm. in diameter 
and almost exactly spherical. Dr. Ruedemann did not gi\e measure- 
ments of his specimen, but on the figure, the glaliella is 10 mm. wide. 
The largest specimen of S. rohusfa Walcott in the M. C. Z. has the 
glabella 4 mm. in diameter. 



RAYMOND: ORDOVICIAN TRILOBITES. 149 



Sphaerexochi's parvus Billings. • 
Plate 10, fig. 5. 

Trilobite, genus undetermined Billings, Canad. nat. geol., 1859, 4, p. 468, 
fig. 37. 

Sphaerexochus parvus Billings, Geol." Canada, 1863, p. 133, fig. 66. Pal. foss. 
Canada, 1865, 1, p. 180, fig. 161a, b. Raymond, Ann. Carnegie mus., 
1905, 3, p. 366, fig. 4, 5; p. 372, pi. 14, fig. 22. 7th rept. Vermont state 
geol., 1910, p. 246, pi. 36, fig. 22. Grabau andShimer,.N. A. index fossils, 
1910, 2, p. 321, fig. 1634e. 

The original localities of this species cited by Billings are the Island 
of Montreal, and the south side of Large Island, ^Vlingan Islands. 

Specimens of the glal)ella are quite common in the top of the Holston 
northeast of Blacksburg, in the strata characterized b\' Agnostns. 
These glabellae are of the same size as those found in the north, and 
like them, the posterior furrows entirely encircle the basal lobes, 
whereas the two anterior pairs are faintly impressed. The anterior 
furrows are short, and almost straight, rimning directly upward and a 
little backward. The basal lobes are nearly circular in outline. The 
fixed cheek is perhaps a trifle shorter than on specimens from the Chazy 
of the Champlain Valley, and is deeply indented by the occipital 
furrow. The surface of the glabella is minutely tuberculated. 

The pygidium of this species has not previously been known. 1 
found two in the Holston at the Thomas farm, and one in the lower 
part of the Lenoir at Bluff City. It is a small, only slightly convex 
plate, each of the pleural lobes bearing three prominent convex ribs 
which end in short, blunt, separated points. The axial lobe has two 
narrow rings beside the anterior half-ring, and ends in a triangular 
median piece between the last pair of pleural ribs. 

Mrasurrnirnfs: — A cranidium from the Holston on the Thomas 
farm is 5 mm. long, about 7 mm. wide; and the glabella is 5 mm. wide. 
The pygidium figured, which is from the same locality, is 2 mm. long, 
and 3 mm. wide. A somewhat larger one from Bluft" City is 2.5 mm. 
long, and 4 mm. wide. 

Horizon and Localiiy: — The typical localities are in the Upper 
Chaz\'. In the Champlain Valley the species ranges throughout the 
Chazy. In Virginia it is common at the top of the Holston, three 
miles northeast of Blacksburg, and present, though rare, in the Liberty 
Hall at Lexington, and at the top of the reef in the Holston at the 
Hoge farm. Bland Co., Va. It is also common in the Lenoir east of 
Bluff City, Tenn. 



150 bulletin: museum of comparative zoology. 

'Sphaerexochus discrepans, sp. nov. 
Plate 10, fig. 3, 4. 

Glabella highly convex, but when viewed from above, half oval 
instead of circular in outline. There are three pairs of glabellar fur- 
rows, the first two pairs very faint, the last ones deeply impressed. 
Both the first two pairs of furrows are straight, and the first furrows 
as long as the second ones. The last pair turn backward, but do not 
quite reach the occipital furrow, ending abruptly in deep depressions. 
On some specimens a shallow furrow connects this depression with the 
occipital furrow. The fixed cheeks are short and narrow, crossed 
by the deep occipital furrow. The surface is practically smooth, or 
faintl.\' granulose. 

Measurements: — An average cranidium in 7 mm. long, and 8.5 mm. 
wide; the glabella is 6.5 mm. wide. A large glabella is 9 mm. long; 
a small one, 5 mm. 

This species differs from Sphaerexochus parvus principally in the 
failure of the posterior glabellar furrows to reach the neck-furrow. 
The surface is also smoother, and some though not all of the specimens 
are less nearly spherical. 

Horizon and Locality: — This species is common in the Holston at 
the McNutt quarry near Sharon Springs, Bland Co., Va., and in the 
reef of the Holston on the Hoge farm in the same county. One speci- 
men was found associated with Sphaerexochus parvus in the top of the 
Holston, three miles northeast of Blacksburg, Va. The cotypes 
(M. C. Z. 1,621, 1,622) are from the McNutt quarry. 

Sphaerexochus romingeri Hall. 

Plate 10, fig. 1, 2. 

Sphaerexochus romingeri Hall, 20th rept. N. Y. state cab. nat. hist., 1868, p. 
375, pi. 21, fig. 4-7. Bassler, Bull. 92, U. S. N. M., 1915, p. 1167. 

No complete specimen of this species, has previously been figured, 
nor has the hypostoma been before recognized. The Day collection 
contains two small entire specimens, one of them retaining the h\po- 
stoma in position. ^Yeller reported an entire specimen from Madison, 
Ind., but did not figure it. If other complete specimens exist, they 
have not been mentioned in the literature. 

Sphaerexochus is one of the most stereotyped of all fossils, showing 



RAYMOND: ORDOVICIAN TRILOBITES. 151 

very little variation except in size. It is, therefore, not surprising 
that there should he little difference between 8. roiningeri and S. mirus 
Be\rich, which is a common fossil in the Silurian of Bohemia. In the 
latter species the anterior glabellar furrows are somewhat more 
pronounced, the posterior part of the facial suture cuts the margin a 
little farther from the axis, and the pygidium is more spinose than in 
the American form. 

There is some indication that more than one species is included 
under S. romingpri. Many specimens ha\'e the basal glabellar lobes 
rudely quadrangular instead of subcircular, and there are differences 
in the free cheeks. Weller (Chicago acad. sci., Bull. 4, 1907, pi. 24, 
fig. 17, 18) has figured a cephalon which has the anterior ends of the 
free cheeks extending downward nearly perpendicularly to the plane 
of the base of the glabella. Most specimens show free cheeks which 
become pointed at the front, and so lack this square appearance. 

Foerste (Bull. Denison univ., 1888, 3, pi. 13, fig. 6) described and 
figured a cranidium from Cedarville, Ohio, which is slightly longer than 
wide, whereas, the usual specimen is wider than long. It also has a 
small tubercle on the occipital segment near the place where the facial 
suture terminates. This has not been found on other specimens. 

The hypostoma of »S'. roiningeri, as shown by the figure, is a short 
plate. The lateral margins converge backward, and the posterior one 
is gently convex in outline, lacking the small median notch present 
on the lip of 8. mirus. It occupies a wide space under the front of the 
cephalon between the anterior ends of the free cheeks. At the ante- 
rior corner of each free cheek there is a tubercle on the rounded border. 
The preservation is not good enough to allow the course of the facial 
suture across the front to be followed, so that it cannot be determined 
whether or not an epistoma is present. 

The hypostoma does not lie in the plane of the lower surface of the 
glabella, but is turned downward so that it is nearly in line with the 
margins of the free cheeks. 

Horizon and Locality: — The two entire specimens are from the 
Racine dolomite at Wauwatosa, Wis., and the figured one is in the 
Day collection, (M. C. Z. 1,876). 

Sphaerexochus desertus (Billings). 

Harpides f desertus Billings, Pal. foss. Canada, 1865, 1, p. 333, fig. 321. 

Harpides f desertus was described by Billings from a small glabella 
found in the bed of the Pike River at the village of Bedford, Que. 



152 bulletin: museum of comparative zoology. 

Two small cranidia of what seem to be tlie same species were obtained 
by Schuchert and Twenhofel in Newfoundland. As seen partly 
imbedded in the matrix they look like glabellae of Cyphaspis, l)ut on 
cleaning appear to be either Sphaerexochus or Kawina, and because 
of the narrow fixed cheeks, are referred to the former genus. 

Cranidium small, subglobose, the glabella making up its greater 
portion. The fixed cheeks are small, situated chiefly back of the eye, 
triangular, deflected downward. The glabella is large, convex, 
abruptly incurved at the front, pustulose. There are three pairs of 
glabellar furrows, the first two pairs short and narrow, indenting the 
sides only, the posterior pair deeper, and setting off a pair of small basal 
lobes. The eyes are situated well forward, opposite the outer ends of 
the posterior glabellar furrows, and close to the dorsal furrows. There 
is a small median tubercle on the nuchal segment. 

Measuremcnis: — The larger cranidium is 5 mm. long; and the 
glabella is 3.25mm. wide at the middle. Billings's glabella of Harpidesf 
deserhis was 5 lines (10 mm.) long, and 3 lines (6 mm.) wide at the neck- 
furrow. • 

This species differs from all" others of the genus in its less spherical 
glabella and smaller and less circular basal lobes. 

Horizon and Locality: — Schuchert and Twenhofel collected one 
cranidium in zone Mo, Table Head, and two, one of which was later 
destroyed, in the Isolated limestone, Ni, Table Head, Nfld. The type 
was found at Bedford, Que. 



Pliomerops canadensis (Billings). 

fCalymene multicosia HaU, Pal. N. Y. 1847, 1, p. 228, pi. 60, fig. 31. 

Amphion canadensis Billings, Canad. nat. geol., 1859,4, p. 381, fig. 12. Geol. 

Canada, 1863, p. 133, fig. 69. Pal. foss. Canada, 1865, 1, p. 288, fig. 278. 

Raymond, Ann. Carnegie mus., 1905, 3, p. 363, pi. 14, fig. 10-13. 
Pliomera canadensis Grabau and Shimer, N. A. index fossils, 1910, 2, p. 321, 

fig. 1634a-c. 
Pliomerops canadensis Raymond, Amer. journ. sci., 1905, ser. 4, 19, p. 378. 

Ann. Carnegie mus., 1910, 7, p. 75, fig. 4 and 6, pi. 18, fig. 14. 7th rept. 

Vermont state geol., 1910, p.238, pi. 36, fig. 10-13, pi. 38, fig. 14. Perkins, 

8th rept. Vermont state geol., 1912, pi. 18, fig. 14. 

Specimens of this species in the Lenoir appear to be identical in all 
important features with those found in the Chazy of the Champlain 
Valley. No good pygidia ha\'e been found, but the shape of the 
glabella, number, position, and direction of the glabellar furrows,. 



RAYMOND: ORDOVICIAN TRILOBITES. 153 

position of the eyes, form of the thoracic segments, and ornamentation, 
are all the same as in specimens from Lake Champlain. The best 
specimen found shows the cranidium and sixteen segments of the 
thorax. The glabella, including the neck-segment, is 11 mm. long and 
14 mm. wide, and the whole length of the specimen as preserved is 
49 mm., indicating a specimen somewhat smaller than the largest 
found farther north. 

Horizon and Locality: — The original localities cited by Billings 
were the Mingan Islands and Montreal, at both of which localities the 
strata are of Upper Chazy age. Schuchert and Twenhofel found it 
in zone A3 of their Mingan formation. Near the lower end of Lake 
Champlain the species is found all through the Chazy, but is most 
abundant at the base of the upper part. In the Lenoir it is fairly 
common about six miles southeast of Knoxville in the large area ex- 
posed in the anticline southeast of the Ross Republic quarry. 



Pliomerops barrandei (Billings). 

Amphion barrandei Billings, Pal. foss. Canada, 1865, 1, p. 288, fig. 277a, b. 
Pliomerops barrandei Raymond, Ann. Carnegie mus., 1910, 7, p. 76, fig. 7. 

This species has a greater vertical range than any other found in 
Newfoundland and is a common form at several horizons, and yet, 
strangely enough, has never before been found outside that island. 
Known to Billings from fragments only, practically complete speci- 
mens have since been collected, so that all part-s are now known. 

Entire specimen elongate oval, tapering gently from cephalon to 
pygidium. 

Cephalon approximately semicircular, with rounded genal angles. 
Around the sides and front is a narrow convex rim, which in front of 
the glabella, has a single notch on the median line. The glabella is 
evenly convex, but not raised greatly above the cheeks. It expands 
somewhat toward the front, and the dorsal furrows are nearl\- straight. 
Three pairs of deep glabellar furrows are pi'esent, the first pair being 
elongate depressions set diagonall;^' in the frontal lobe; the other two 
are lateral and open into the dorsal furrows. The first pair reach 
almost to the narrow furrow in front of the glabella, but do not open 
into it. The eyes are situated close to the dorsal furrows and well 
back on the cheeks, about their own length in front of the neck-furrow. 
The facial sutures meet the lateral margin well in front of the genal 
angles and the anterior margin outside the dorsal furrows. The 



154 bulletin: museum of comparative zoology. 

exfoliated specimens commonly found do not show the surface mark- 
ings, but well-preserved specimens are covered with fine tubercles. 

The hypostoma is shaped like that of Ceraurus, but has wide wings 
at the sides and an indistinct keel on the median line. 

The thorax has fifteen segments. The axial lobe is convex, and one 
third the total width. The pleural lobes are flat on top, abruptly 
deflected at the sides. Each pleuron is nearly flat on the top, and has 
no furrow, but the central elevated portion has a very narrow anterior 
and posterior border at a lower level. 

Pygidium rounded, the five pairs of ribs ending in spines. The 
axial lobe has five rings, the first three or four of which curve forward. 
It terminates in a shield-shaped boss which is pointed behind, and 
bears a deep semicircular furrow which is convex backward and bounds 
a low mound at the front of the shield. The pleural ribs of small 
specimens are rather slender, but in large ones they are broad and flat. 

Measurements: — A small specimen from zone 11 is 51 mm. long. 
A cephalon and thorax from Gargamella Cove is 50 mm. long, and 
35 mm. wide at the genal angles. The cephalon of this specimen is 
16 mm. long, the glabella 11 mm. wide at the back and 11 mm. wide 
at the front, an enlargement of 1 mm. in 15 mm. A small pygidium 
from zone 1 1 is 10 mm. long, and 13.5 mm. wide. A large one from the 
same zone is 35 mm. long. 

This species is nearly allied to P. canadensis of the Chazy and 
Lenoir but differs in having isolated anterior glabellar furrows, and 
the eyes closer to the glabella. The thorax has only fifteen instead of 
nineteen segments, and the shield at the posterior end of the axial 
lobe of the pygidium is larger and more differentiated. 

Horizon and Locality: — Billings reported this species from horizons 
I, K, L, Point Rich; L, M, N, Table Head, and Bonne Bay; and P, 
Portland Creek, and Cow Head. Professors Schuchert and Twenhofel 
found it in zone 3100-4 at Port au Choix (2 specimens); zone 10 
(3100-6) at Point Rich (4 specimens); (3100-7) Point Rich (2 
specimens); zone 11 (3100-8), Point Rich (21 specimens); (3100-9, 
Point Rich (4 specimens); Leperditia bed (3100-14) Table Head 
(10 specimens); zone Mi (3100-15) Table Head (6 specimens); zone 
Ma (3100-16) Table Head (10 specimens); zone Nj (3100-17) Table 
Head (10 specimens); and Isolated limestone (3100-18) (1 specimen). 

It was not found in higher strata. Professor Hyatt collected speci- 
mens, now in the M. C Z., from the western side of Gargamella Cove, 
Nfld. In a small collection from the Simpson formation in the 
Arbuckle Mts., Okla., sent me by Prof. L. E. Trout, formerly of 



RAYMOND: ORDOVICIAN TRILOBITES. 155 

Norman, 1 find one glabella and one pygidium that must be referred 
to this species. The glabella shows the characteristic isolated frontal 
furrows and the pygidium has the typical shield at the end of the axial 
lobe. These two specimens are from the lower part of the Simpson, 
one half mile southeast of Crusher, in the cutting on the Gulf, Colorado, 
and Santa Fe Railroad. 

Pliomerops sp. 

Pliomera afi. barrandei Billings. Reed, Quart, journ. Geol. soc. London, 1910, 

66, p. 145, pi. 6, fig. 5. 
Acidaspis (?) sp. Reed, Ibidem, p. 148, pi. 6, fig. 8. 

The pygidium of a Pliomerops, which is certainly very like P. bar- 
randei, has been figured by Reed from Ireland. The axial lobe shows 
five rings and a triangular terminal piece, and there are five pairs of 
somewhat divergent ribs, ending in free spines. Another less perfect 
specimen was figured as possibly a species of Acidaspis. 

Horizon and Locality: — These specimens were from the Shangort 
beds, of the Tourmakeady district. County Mayo, and from the cal- 
careous ash southwest of Garranagerra, Glensaul district, County 
Galway, Ireland. 

Pliomerops julius (Billings). 
Amphion Julius Billings, Pal. foss. Canada, 1865, 1, p. 290, fig. 279. 

This species has previously been known from the pygidium only. 
Although no entire specimens are yet at hand, cephala and pygidia 
with portions of the thorax attached permit the description of all parts. 

Cephalon short, wide, strongly elevated, highest near the posterior 
margin. Glabella ovate, widest at the second pair of lobes, and taper- 
ing backward to the neck-ring. The dorsal furrows are deep at the 
sides, but narrow and shallow in front of the glabella. There are 
three pairs of short glabellar furrows, the first of which are directed 
slighth' backward. The posterior lobes are very narrow. The 
cheeks are convex, w^ith an elevated border separated from the mound- 
like inner portion by a deep furrow. The genal angles are obtusely 
rounded, and an isolated cheek strongly suggests an hypostoma. The 
eyes are small, situated well forward and close to the glabella. The 
posterior portion of the facial suture turns first outward into the 
marginal furrow, and then backward to the genal angle. The surface 
of the cheeks is covered with small pits. That of the remainder of 
the head appears to be smooth. 



156 bulletin: museum of comparative zoology. 

The thorax consists of at least fourteen segments, possibly more. 
The axial lobe is narrow and elevated, the pleural lobes flat on top, 
abruptly deflected at the sides. The pleural part of each segment 
bears a high narrow median ridge, and both it and the axial ring are 
conspicuously tuberculate. 

The pygidium is convex, with a prominent axial lobe bearing nine 
or ten rings. The pleural lobes have five pairs of elevated ribs which 
end in somewhat divergent spines. The surface is covered with small 
tubercles. 

This species is, as Billings noted, remarkable for the great number 
of rings on the axial lobe of the pygidium. 

Measurements: — A cephalon and fourteen thoracic segments are 
together 22 mm. long; the cephalon is 7 mm. long, and 15 mm. wide; 
the glabella is 7 mm. wide at the second lobes. The axial lobe of the 
thorax is 5 mm. wide at the seventh segment, where the total width is 
about 15 mm. 

Horizon and Locality: — The original specimens were from the con- 
glomerates of division P at Cow Head, Nfld., and those collected by 
Schuchert and Dunbar are from the same locality. 

Pliomerops bilirata, sp. nov. 

Plate 10, fig. 6, 7. 

Cranidium small, short, wide, and highly convex. Glabella about 
one third the total width, as wide as long, depressed convex. There 
are only two pairs of glabellar furrows, which are short, straight, deep 
indentations in the sides of the glabella, so placed that the lateral 
lobes are subequal, although the hindmost ones are smallest. The 
eyes are small and high, situated opposite the second glabellar lobes 
and third furrows and close to the dorsal furrows. The cheeks are 
wide, with an unusually wide elevated border on the free cheeks. In 
front of the glabella this border becomes nearly vertical, so that 
little of it is seen from above. The genal angles are rounded. 

The anterior portion of the facial suture extends from the eye 
downward and forward parallel to the dorsal furrow nearly to the 
front, then turns diagonally inward and crosses the furrow and mar- 
gin, reaching the lower edge of the margin close to the median line. 
Back of the eye the suture extends out parallel to the nuchal furrow 
until it reaches the depression which separates the main portion of the 
cheek from the border, then turns diagonally backward, and meets 
the outer margin but slightly in front of the angle. 



RAYMOND: ORDOVICIAN TRILOBITES. 157 

The surface is so completely exfoliated that no markings can be 
detected. The cheeks were probably not deeply pitted, or depressions 
would be present on the cast. 

Measurcme7its: — The most complete cephalon (the holotype) is 
5.5 mm. long, and 11 mm. wide. The glabella is 5 mm. long, including 
the neck-ring, and 4 mm. wide at the frontal lobe. The width at the 
palpebral lobes is 8 mm. 

The absence of the anterior pair of glabellar furrows is so striking 
a feature that detailed comparison with other species is unnecessary. 
The eyes are also higher, farther back, and closer to the glabella than 
is usual in this genus. 

Horizon and Locality: — A rare fossil in a boulder in the conglomer- 
ate on lot 22, concession VI, two miles north of Mystic, Que., where it 
is associated with Normanskill fossils. Holotype (M. C. Z. 1,758). 

Pliomerops nevadensis (Walcott). 

Plate 10, fig. 15. 

Amphion nevadensis Walcott, Monogr. 8, U. S. geol. surv., 1884, p. 94, pi. 12, 
fig. 13. 

This species was described originally from the Upper Pogonip lime- 
stone of the White Pine district in Nevada, but Ulrich has identified 
it also in the Lower Simpson of the Arbuckle Mts., Okla. Dr. 
Walcott described only the cranidium, but pygidia, which because of 
their large size, are referred to this species, seem to be quite common 
in Oklahoma. The present description is derived from two incom- 
plete cranidia and five more or less imperfect pygidia. 

Entire specimens of large size for a Pliomerops. Glabella almost 
rectangular, longer than wide, expanding only very slightly toward the 
front. There are three pairs of glabellar furrows, those on the same 
side all parallel, and so long that their proximal ends almost meet. 
The posterior furrows open into the dorsal furrows, but the anterior 
ones do not quite reach the furrows, but if continued would bisect the 
anterior lateral angles of the glabella. The eyes are distant both from 
the posterior margin and the dorsal furrows and situated at the horizon 
of the outer ends of the second glabellar furrows. The surface of the 
glabella is covered with small rounded pustules while the cheeks are 
covered with large pits. 

The pygidium is similar to that of other species of Pliomerops with 
five pairs of broad pleural ribs which end in spines, while on the axial 



158 bulletin: museum of comparative zoology. 

lobe are five ribs and behind it a long shield-shaped piece which pro- 
jects far back between the last pair of pleural ribs. On the anterior 
portion of this shield there is a pair of slightly curved furrows parallel 
to the sides, which do not connect with each other. 

Mcasurcmruis: — A cranidium is about 31 mm. long, and was pro- 
bably about 60 mm. wide when complete. The palpebral lobe is 10 
mm. in front of the neck-furrow and 9 mm. from the dorsal furrow. 
The largest pygidium was aljout 32 mm. long, and 60 mm. wide when 
complete. 

Horizon and Localiiy: — The specimens here described were col- 
lected by Prof. L. E. Trout from the Lower Simpson, Fall Creek and 
Cool Creek, and along the Gulf, Colorado and Santa Fe Railroad, in 
the Arbuckle Mts., Okla. The cranidium figured is M. C. Z. 1,642. 



Pliomerops trouti, sp. nov. 
Plate 10, fig. 14. 

A third species of Pliomerops in the Simpson is represented by an 
imperfect cranidium. The cephalon is nearly semielliptical in outline, 
evenly convex, with a narrow convex border. Glabella but little 
longer than wide, expanding toward the front, depressed convex. All 
three pairs of glabellar furrows are long and deeply impressed and all 
enter the dorsal furrows, the anterior ones just behind the anterior 
angles of the glabella. The frontal and glabellar lobes are all narrow, 
and the furrows all cur\'e somewhat backward. The eyes are situated 
far forward, close to the anterior margin, and far from the dorsal and 
nuchal furrows. The cheeks are covered with pits and pustules, and 
the glabella with low pustules. 

Measurements: — The cephalon when complete was about 13.5 mm. 
long, and about 36 mm. wide. The glabella was about 12 mm. long, 
and 12 mm. wide at the front. 

This species is more nearly allied to Pliomerops canadensis than to 
any other species, but differs in the position and great length of the 
anterior glabellar furrows. It has a much shorter glabella than P. 
nevadensis, and the anterior furrows are not isolated as in P. harrandei 
and P. nevadensis. 

Horizon and Locality: — The holotype (M. C. Z. 1,662) was collected 
by Prof. L. E. Trout in the Lower Simpson, Arbuckle Mts., Okla., 
one half mile southeast of Crusher, in a cutting of the Gulf, Colorado, 
and Santa Fe Railroad. 



RAYMOND: ORDOVICIAN TRILOBITES. 159 

Perischoclonus, gen. nov. 

This generic name is proposed for a small trilobite which is referred 
with considerable doubt to the Cheiruridae, l)ut which may belong in 
the Opisthoparia. AVith such confusion existing, it is not possible to 
give a complete generic diagnosis, but the chief characteristics are the 
long glabella which expands toward the front, three pairs of glal)ellar 
furrows developed as pits, and eyes rather distant from the glabella 
and far back. Type: — Prrischodomis capifalis, sp. nov. 

The uncertainty as to the systematic position of this species arises 
from the fact that on the only specimen the course of the posterior 
portion of the facial suture is obscured, apparently by fusion, for the 
shell is well preserved. There are two or three lines which might be 
taken for the suture, and the most prominent of these seems to cut the 
genal angle or just within it. Trilobites with small eyes and long 
expanding furrowed glabella are not common, hence the comparison 
of this cephalon to that of some species of the Cheiruridae. Among 
the Opisthoparia only a few of the species of Karlia and Corynexochus 
of the Middle Cambrian seem to possess the same combination of 
characteristics. 

Perischoclonus capitalis, sp. nov. 
Plate 10, fig. 13. 

Cephalon nearly semicircular in outline, moderately convex, with 
long prominent glabella. The dorsal furrows are narrow, deep, with 
a V-shaped section, and converge backward to the horizon of the eyes, 
then diverge slightly to the neck-furrow. There are three pairs of 
glabellar furrows, represented by pits close to the dorsal furrow. The 
posterior pair are bifurcated, Y-shaped, one arm of the Y extending 
forward and one backward, the short stem connecting laterally with 
the dorsal furrow. The fixed cheeks are wide, higher than the free 
cheeks, and the eyes are situated just outside the highest point, on the 
laterahslopes. The free cheeks descend steeply to the narrow flattened 
border. This border is widest at the anterior ends of the dorsal fur- 
rows, and very narrow in front of the glabella. 

From the eye the facial suture pursues a nearly straight course 
across the cheek to the depressed border, where it curves slightly 
inward, reaching the margin in front of the dorsal furrow. As stated 
above, the course back of the eve is unknown. 

The surface of both glabella and cheeks is covered by very small 



160 bulletin: museum of comparative zoology. 

pustules which are somewhat more pointed on the glabella than on the 
cheeks. 

1 do not know any other trilobite which is liable to be confused with 
this one. 

Measure menis: — Length of cephalon, 5.5 mm., width 9 mm. 

Horizon and Locality: — The type was collected from a pebble in the 
Cow Head conglomerate at Lower Head, Nfld. In the same fragment 
of rock is a shield of Arthrorhachis galba, indicating the Normanskill 
age. The holotype is in the Yale University Museum. 

Phacopidae Corda. 

,-| Pterygometopus annulatus Raymond. 

Plate 10, fig. 16, 17. 

Vterygometopus annulatns Raymond, Ann. Carnegie mus., 1905, 3, p. 376, 
pi. 14, fig. 24, 25. 7th rept. Vermont state geol., 1910, p. 247, pi. 36, fig. 
24, 25. 

A Pterygometopus which 1 cannot at present distinguish from P. 
annidatns occurs in various places in the Holston, Ottosee, and Athens. 
The cephalon differs so slightly from that of P. callicephaliis Hall of 
the Trenton that specimens can only be separated by direct comparison. 
The anterior glabellar lobes are somewhat longer in the specimens 
from the Normanskill than in those from the Trenton and the second 
pair somewhat smaller. The pygidium, like that of P. annulatus, is 
somewhat variable, and shows this variation most in the point at which 
the ribs on the pleural lobes bifurcate. In some specimens they 
divide xevy close to the dorsal furrows, as in P. callicephaliis, whereas 
in others they do not bifurcate until they reach the slope of the lobe. 

No entire specimens have been seen, the largest piece being a py- 
gidium with eight thoracic segments attached. 

Measurements: — A pygidium and eight thoracic segments are 
together 28 mm. long, and 20 mm. wide at the anterior end. The 
axial lobe at the front is 8 mm wide. The pygidium is 13 mm. long, 
and about 17 mm. wide at the anterior end. An unusually large ceph- 
alon is 20 mm. long, and 25 mm. wide. The eyes are 6 mm. long, the 
frontal lobe is 7 mm. long, and 18.5 mm. wide. 

Horizon and Locality: — The original locality for this species was 
Valcour Island, N. Y., where it ranges throughout the Chazy. It 
is present, though not common, in the chert of the lowest part of the 
Holston on New River, Va., two miles east of Goodwins Ferry, and 1 



RAYMOND: ORDOVICIAN TRILOBITES. l&l 

have one specimen from the same horizon in the Catawba Valley. 
It is fairly common in the Liberty Hall near the reservoir at Lexington, 
Va., is extremely abundant in the thinly bedded limestone of the middle 
part of the Athens in the railroad cutting one mile south of Otes, Tenn., 
and is found in the Athens at Chatham Hill, north of Marion, Va. On 
the hills east of the quarries at Saltville, Va., it is quite common in 
beds which have been called Ottosee, and Dr. Shuler collected many 
specimens farther north on Walker Mt., at Tilsons Gap, Va. The 
figured specimens (IVI. C. Z. 1,665-1667) were found in material 
brought from the cutting near Otes, Tenn. 



Pterygometopus holstonensis, sp. nov. 
Plate 10, fig. 9-11. 

This species is known only from imperfect cephala and pygidia, but 
is readily recognized by its distinctive glabella. 

Cephalon rather evenly vaulted, relatively smooth for the genus. 
Glabella depressed convex, uniformly curved, covered with small 
tubercles. All glabellar furrows are narrow, distinct, but not deeply 
impressed. The anterior ones are not straight as in most species of 
the genus but doubly curved, becoming straight toward their proximal 
ends. The second furrows are short and do not unite with the dorsal 
furrows, so that the two principal lateral lobes on each side are con- 
fluent. The basal lobes are small. The eyes and free cheeks are not 
well shown on any of the specimens, but seem to be of normal size. 

The pygidium associated with these cephala is rather short for a 
Pterygometopus, highly \'aulted with a prominent axial lobe. The 
axial lobe has about eight distinct rings which cross it directly and the 
pleural lobes show seven pairs of ribs, which do not bifurcate in most 
cases though some specimens do show a weakly impressed line along 
the middle of each rib. 

Measurements: — The largest cephalon is 14 mm. long, and about 
20 mm. wide. The glabella is 12.5 mm. wide at the front; and the 
eye approximately 6 mm. long. The largest pygidium is 8 mm. long, 
and 11 mm. wide. The axial lobe is 4 mm. wide at the front. 

I do not know any other American species of Pterygometopus which 
has doubly curved anterior glabellar furrows like this one, and only 
P. eboraceus Clarke shows a tendency toward fusion of the glabellar 
lobes. The fragmentary specimen described b,\' Ruedemann as P. 
eboraceus from Rysedorph Hill (Bull. 49, N. Y. state mus., 1902> 



162 bulletin: museum of comparative zoology. 

p. 69, pi. 4, fig. 15) is much like P. holstonensis, but the anterior furrows 
do not have the double curvature. 

Among the European species I have seen nothing closely comparable, 
unless it be P. hrongniarti Portlock. Some of the specimens figured by 
Salter (Palaeontogr. soc, 1864 (1866), p. 34, pi. 1, fig. 20a) as belong- 
ing to this species have somewhat doubly curved anterior furrows and 
confluent lateral lobes. 

Horizon and Locality: — This species has so far been found only in 
the Holston limestone on the Hoge farm. Bland County, Va. The 
cotypes are M. C. Z. 1,644-1,646. 



Pterygoimetopus gracilens, sp. nov, 
Plate 10, fig. 18. 

The head is represented by the median portion of the cranidium only. 
This is a miniature of P. anmdaius, and needs no especial description. 
All the glabellar furrows connect with the dorsal ones, the glabella 
contracts rapidly to the nuchal segment, and the surface is covered 
with small granules. 

The pygidium is triangular, the sides nearly straight, and is so high 
that it appears narrower than it really is. The axial lobe is narrow, 
and extends nearly, but not cjuite to the posterior end. It bears eight 
defined rings, and is obscurely segmented to the posterior end. 

The pleural lobes are steep slopes, each with eight flat, furrowed 
ribs. The median groove on each rib extends obscurely to the dorsal 
furrow. Surface minutely granulose. 

Measurements: — A cranidium is 4.75 mm. long; the width of the 
frontal lobe of the glabella being 4.00 mm. ; the width at the palpebral 
lobes 5.25 mm., and at the nuchal segment 1.90 mm. 

A pygidium, the holotype, is 4.5 mm. long, and about 4.5 mm. wide; 
the axial lobe is 2.00 mm. wide at the front, and 3.75 mm. long. 

The head is, so far as the imperfect specimens show, of the same 
type as Pterygometopus callicephalus Hall and P. anmdaius Raymond, 
being distinguishable only by its small size. The pygidium is, how- 
ever, much more triangular than that of either of those species, and 
has the same outline as P. intermedius Walcott (Clarke, Pal. Minn., 
1897, 3, pi. 2, p. 727, fig. 47). 

It differs from the latter in having a somewhat shorter axial lobe, 
and in having all the ribs of the pleural lobes furrowed. 



RAYMOND: ORDOVICIAN TRILOBITES. 163 

Horizon and Locality: — This species is very common in the lower 
part of the Lenoir, one mile east of Bluff City, Tenn. Holotype 
(M. C. Z. 1,725). 

Pterygometopus transsectus, sp. nov. 
Plate 10, fig. 12. 

This species may be described briefly by stating its differences from 
other species of the genus. From nearly all American species it 
differs in having a practically smooth surface, the tubercles being very 
low and inconspicuous. The first of the side lobes is also unusually 
small and narrow, and the second side lobe is pointed on the distal end. 
The basal lobes which in most species are small, are relatively large 
and mound-like, and situated farther from the median line than is 
usual. 

Were these characteristics less distinctive I should hesitate to de- 
scribe a species on the little material so far found, but as there seems 
to be no other described smooth Pterygometopus with glabellar lobes 
like this, there will be no difficulty in its recognition. 

Measurements: — Length of cephalon, about 4.5 mm., width 9 mm. 

Horizon and Locality: — A very rare fossil in the coarsely crystalline 
strata at the top of the Holston, three miles northeast of Blacksburg, 
Va. Holotype (M. C. Z. 1,641). 



FAUNAL ASSOCIATIONS. 
The Trilobites of the Ordovician of Newfoundland. 

The greater part of the collection from Newfoundland which was 
studied in the preparation of this paper was made by Professors 
Schuchert, Twenhofel, and Dunbar, and it is not the province of the 
writer to discuss the stratigraphy or complete faunal associations. 
This will be done by Professors Schuchert and Dunbar. For the 
present, the stratigraphy as outlined in the Geology of Canada, 1863, 
will form the basis for the order of succession. 

Three rather distinct faunal associations will be observed. The 
first and oldest- is a small one, found in divisions F, G, and H of 
Logan's section. 



164 bulletin: museum of comparative zoology. 

Trilobites of Divisions F, G, H. 

Petigurns new (Billings), P. timon (Billings), Bathyurellvs ahniptiis 
Billings, B. viarginatiis Billings, Isoteloidcs whitfieldi Ra^Tnond. 

Billings listed from the same zones the following, in addition to the 
above : — 

Hystricurus cordai (Billings), Goniurus caudatus (Billings), " Doli- 
chornetopus" convexus Billings, "D." gihbendus Billings, Pliomerops? 
insidaris (Billings). 

The recent study has added nothing to this fauna, which, as pointed 
out by Billings, is of Beekmantown age. 

Petigurns new and P. titnon have not been found outside of western 
Newfoundland, but the former is very similar to P. cyhele, which occurs 
in the Beekmantown on the Mingan Islands. Batkyurclliis ahruptus 
also has no value in correlation, but B. marginatus is quite similar to a 
species found in division B of the Beekmantown at Philipsburg. 
Isoteloides ivkiffieldi is a common member of the Fort Cassin fauna, 
but probably has a considerable vertical range. 

Hystricurus cordai is known from division B at Philipsburg, Que., 
and from the upper part of the Beekmantown at Beekmantown, N. Y., 
and Goniurus caudatus is a typical Fort Cassin fossil. The two species 
referred to Dolichometopus are very like the third species D. rarus, 
described by Billings from the Beekmantown at Oxford, Ont. It is 
there associated with Pliomerops saJteri, which may be a relative of 
the little known P. f insularis of Newfoundland. 

On the whole, the trilobites here listed would indicate a middle or 
upper Beekmantown age for the strata from which they were obtained. 
There is no trace of any member of the Ceratopyge fauna, or of any 
European element. 

Trilobites of Divisions I, K, L. 

Bathyurcllus validus Billings (also in N), Ulaenus consimilis Billings 
(also in M and N), /. fraternus Billings (also jp N), /. marginalis 
Raymond (also in M), /. aheatus Raymond, Ectenonotus westoni 
(Billings), Nieszkowskia perforator (Billings), A'^. excelsa Raymond, 
Pliomerops harrandei (Billings) (also in M and N), Acidiphorus 
spinifer Raymond (also in M). 

Billings records Asaphus canalis Conrad from these divisions, but 
in the absence of material, I cannot determine what species is so 
designated. 



RAYMOND: ORDOVICIAN TRILOBITES. 165 

Most of the trilobites listed above have not been found below division 
L, and, as indicated, six of them occur in divisions M or N or both. 
None occurs in any division below I. 

This fauna has no exact counterpart in America, but its affinities 
are with that of the Chazy. 

BaihyurcUus validus is unlike the two species of that genus in the 
Beekmantown, but allied to B. minor Raymond, of the Middle Chazy 
of Crown Point and Valcour Island, N. Y. 

Illaenus is a rare genus in the typical Chazy, but /. bayfieldi is 
common in the Mingan Islands. Nieszkowskia occurs in the Upper 
Chazy on Valcour Island, and PUomerops canadensis of the Middle 
and Upper Chazy is allied to P. barrandci. Ectenonotus westoni has 
previously been found only in boulders. 

The general similarity of this fauna to that of the Chazy, coupled 
with the fact that six of the species range upward into higher beds, 
Avhich contain a fauna about which there can be no doubt, indicates a 
post-Beekmantown, and probably early or middle Chazyan age for 
these divisions. 

Trilobites of Division M. 

Arfhrorhachis galba (Billings) (also in N), A. longicollis Raymond, 
Harpides concentricus Billings, Raphiophorus semicostatus (Billings) 
(also in N), Lonchodomas normalis (Billings) (also in N), Remo- 
pleurides panderi Billings (also in N), Brontcopsis gregaria Raymond 
(also in N), Niobe quadraticaudata (Billings) (also in N), Illaenus con- 
similis Billings (also in L and N), /. marginalis Raymond (also in L), 
Sphaerexochiis desertus Billings (also in N), PUomerops barrandei 
(Billings) (also in L and N), Acidiphorus spinifer Raymond (also in L). 

Trilobites of Division N. 

Artkrorhachis galba (Billings) (also in M), Raphiophorus semicostatus 
(Billings) (also in M), Ampyx laevhisculns Billings, Lonchodomas 
normalis (Billings) (also in M), Endymionia schucherti Raymond, 
Anisonotus glacialis (Billings), Triarthrus fischcri Billings, Remo- 
pleuridcs panderi Billings (also in M), Robergia schlotheimi (Billings), 
Telephus americanus Billings, Brontcopsis scotica Nicholson and 
Etheridge, B. gregaria Raymond (also in M), Bathyurellus validus 
Billings (also in L), Niobe quadraticaudata (Billings) (also in M), N. 
morrisi (Billings), A^. lineolata Raymond, Nileus macrops Billings, N. 
scrutator Billings, Megalaspis huttoni (Billings), Illaenus consimilis 



166 bulletin: museum of comparative zoology. 

Billings (also in L and M), /. fraternus Billings (also in L), Cyhele 
mira (Billings), Ceraurinus polydorus (Billings), Sphaerexochus 
desertus (Billings) (also in M), Pliomerops barrandei (Billings) (also in 
LandM). 

Billings listed from this div^ision two more species: — 

Petigurus tiero (Billings), Heliomera sol (Billings). 

These two lists show that the two divisions have many trilobites 
in common, and the same general type of fauna characterizes both. 
Lithologically, the strata become increasingly dark, carbonaceous, 
and thinl;^' bedded upward, and there is a corresponding change in 
fauna, as will be brought out by Schuchert and Dunbar. 

Taken as a whole, this is a rather remarkable fauna, and one more 
at home in northern Europe than America. Lonchodomas, Remo- 
pleurides, Bathyurellus, lllaenus, Ceraurinus, Pliomerops, Sphaere- 
xochus, and Heliomera occur in the Chazy, and one of the species, 
Heliomera sol, has been found at Chazy, N. Y., in the upper part of 
the Lower Chazy. 

Arthrorhachis galba, Remopleurides panderi, Bronteopsis gregaria, 
Rohergia schlotheimi, Nileus scrutator, and Pliomerops barrandei are 
shown in this paper to be present elsewhere in America in strata which 
are younger than the Beekmantown and older than the Trenton. 
Endymionia is represented by another species in the Levis shales, and 
Remopleurides, Triarthrus, lllaenus, and Cybele are represented in 
Trenton or post-Trenton formations. 

Trilobites of the Cow Head Conglomerate. 

Arthrorhachis galba (Billings), Eoharpes granti (Billings), E.fragilis 
Raymond, Ischyrotoma twenhofeli Raymond, Bathyurellus nitidus 
Billings, B. formosus Billings, B. fraternus Billings, B. expansus Bill- 
ings, Homotelus catactus Raymond, lllaenus tumidifrons Billings, 
/. consobrinus Billings, Amphilichas jukesi (Billings), Kaivina vidcanus 
(Billings), Hadrohybus dimbari Ra^'mond, Pliomerops barrandei (Bil- 
lings), P. Julius (Billings), Perischoclonus capitalis Raymond. 

The species, listed above were obtained by Professors Schuchert, 
Twenhofel, and Dunbar from the Cow Head conglomerate at Cow 
Head and on Stearing Island, Nfld. It will be noted that only two of 
the species, Arthrorhachis galba and Pliomerops barrandei, appear on the 
preceding lists. The former of these occurs in situ in zones M and N, 
the latter, in zones L, M, and N. Eoharpes granti (Billings) and 
Bathyurellus expansus Billings have been foimd previously only on 



RAYMOND; ORDOVICIAN TRILOBITES. 167 

lot 20, range 6 of Stanbridge, in boulders, and Kawina vulcamis has 
been found at the base of the Upper Chazy on Valcour Island, N. Y. 
Hyatt found a specimen of Bathyurellus fraternus at Gargamella Cove, 
Nfld., where it was associated with trilobites characteristic of zones 
M and N. Eoharpes fragUis, Pliomerops barrandei, Homotelus catactus, 
and Hadrohyhiis dmibari were found in one boulder on Stearing Island, 
and Arthrorhachis galba and Perischodonus capitalis in another at Lower 
Head. 

Ten of the sixteen species are therefore more or less definitely associ- 
ated with zones M or N or the Upper Chazy, and it seems probable 
that all are of about this age. Most of the specimens were obtained 
from a light-colored limestone, quite unlike that of zones M and N, 
and the situation reminds one x^vy much of the relationship of the 
Holston of Virginia and Tennessee to the Athens. 

Coviparison of the faunas in Neufoundland with those of other regions. 

The Glensaul District. 

A fauna which in some respects is strikingly like that of M and N is 
the one described by Reed from the Glensaul District, County Galway, 
Ireland. The following trilobites were found at one or another of six 
localities within an area of less than a square mile (Gardiner and 
Reynolds, Quart, jour. Geol. soc. London, 1910, 66, p. 265). 

Bathyurellus glensaidensis Reed, Bathyurellus sp., Bathyurus aff. 
nero Billings, B. cf. timon Billings, Bronteopsis sp., Calymene sp., 
Cheirurus cf. clavifrons Dalman, C. aff. ornatus Dalman, Pseudosphae- 
rexochus sp., Cybele sp., Encrinurus octocostatus Reed, cf. Ectenonotus 
westoni (Billings), Harpes sp., Illaenus iceaveri Reed, allied to /. 
alveatus Ra\-mond, Illaenus sp., Megalaspis (?) sp., Nileus armadillo 
Dalman, cf. N. scrutator Billings, Niobe sp., compared with N. mor- 
risi (Billings), Chasmops aff. odini Eichwald, Pliomerops aff. barrandei 
Billings, Pliomera pseudoarticulata Portlock, allied Ectenonotus westoni 
(Billings), Remopleurides sp., Sphaerocoryphe sp., Telephus hibernicus 
Reed, allied to T. americanus Billings. 

This is the only extra-American locality at which Bathyurellus has 
been found, and the species is of the B. validus type, not that of the 
Beekmantown. The forms referred to Bathyurus are somewhat of a 
puzzle at present. It will be noted that Billings reported " Bathyurus" 
nero from Division N. Schuchert and Twenhofel collected from that 
horizon fragments of a trilobite which is probably Ischyrotoma twen- 
hofeli, and that may be the species noted by Billings. The presence of 



168 bulletin: museum of comparative zoology. 

Bronteopsis, Cybele, Xileus, Pliomcrops aff. harrandci, and Remo- 
pleurides in the Irish fauna, even though not specifically identified, 
give the fauna an aspect very like that in Newfoundland. As 1 have 
shown (p. 110) Illaeniis weaveri is very closely allied to /. alveatus, and 
Pliomera pseudoartindaia, and Encrinurvs ocfocostatus probably repre- 
sent one species of Ectenonotus allied to E. tcesioni. 

Reed, with some hesitation, placed this fauna in the Arenig, proba- 
bly because all the graptolites in the region were of that age. The 
graptolites and trilobites were not, however, associated, or even in the 
same formations. In view of the close similarity of this fauna to that 
in western Newfoundland, it seems more probable that the original 
reference to the Llandeilo was correct. 



Girvan District, Scotland. 

Reed (Palaeontogr. Society, for 1903, 1904, 1906, 1914) has de- 
scribed the Ordovician trilobites of the Girvan District, Ayrshire. 
In the somewhat unusual faunas of that region, agnostids, ampycids, 
Bronteopsis, Telephus, Remopleurides and other trilobites similar to 
those found in western Newfoundland were obtained from more than 
one horizon. The greatest similarity, however, appears when the 
fauna under discussion is compared with that of the Balclatchie Group. 

The Balclatchie Group has ^'ielded fifty-one species of trilobites, 
only a part of them being allied to those found in Newfoundland. 
The comparable species of the two regions are listed in parallel 
columns: — 

Girvan. Neivfoundland. 

Arthrorhachis girvanensis (Reed), A. galba (Billings). 

Aniso7iotus hornci (Nicholson and Etheridge), A. glacialis (Billings). 
Lonchodomas viacallumi (Salter), L. normcdis (Billings). 

Triarthrus reedi Raymond, T. fischeri Billings. 

Robergiabarrandei (Nicholsonand Etheridge), /?. schlotheimi (Billings). 
Remopleurides girvanensis Reed, R. panderi Billings. 

Telephus salteri Reed, T. americanus Billings. 

Illaenus balclatchiensis Reed, /. fraternus Billings. 

/. latus M'Coy, /. consimilis Billings. 

Bronteopsis scotica Nicholson and Etheridge, B. scotica Nicholson and 

Etheridge. 
B. ardmillanensis Reed, B. gregaria Raymond. 

Cybele michelli Reed, Cybele mira (Billings). 



KAYl^lOND: ORDOVICIAN TRILOBITES. 169 

Twelve of the thirty-one species of trilobites found in divisions M 
and N are closely allied to species found in the Balclatchie Group, and 
the similarity of the two faunas is emphasized by the occurrence in 
each of Anisonotus, a genus unknown outside these formations, and 
Brontcopsis scotica, a species also confined to them. 

Jemtland, Sweden. 

Hadding (Meddel. Lunds geol. faltklubb, 1913, ser. B, no. 6, p. 22 
et seq.) has described the fauna of the Lower Dicellograptus beds 
(Ogygiocarisskiffern) at Anderson in Jemtland. These beds are 
divided into two zones, those characterized by Climacograptus putillus 
below, followed by strata with Nemagraptiis gracilis. The variety of 
trilobites is not great, but includes such significant species as Triarthrus 
humilis Hadding, Megalaspis patagiata Tornquist, Nileus armadillo 
Dalman, Ceraurus exsul (Beyrich), Ampyx clavifrons Hadding, A. 
costahis Boeck, Tcleplms hiciispis Angelin, T. mobergi Hadding, T. 
grannlatus Angelin, Rcmopleurides circiilaris Hadding, R. subquadratiis 
Hadding, and Robcrgia micropthalma Linnarsson, besides six species 
not yet known to be represented by related forms in Newfoundland. 

Scania, Sweden. 

Funkquist (Meddel. Lunds geol. faltklubb, 1919, ser. B, no. 11) has 
studied the shales between the Orthoceras limestone and the zone of 
Dicranograptus clingani in southeastern Scania, and shown that they 
represent the upper part of the Lower Dicellograptus zone, and the 
lower part of the Middle Dicellograptus zone of western Scania. There 
are but few trilobites, only nine specifically identified, in the zone next 
above the Orthoceras limestone, but seven of these are important for 
our correlation. They are Lonchodomas rostratus (Sars), Nileus 
cornutus Moberg, N. superestes (Olin), Brontcopsis conccntrica (Lin- 
narsson) (a form very close to B. scotica), Rcmopleurides subquadratus 
Hadding, Tclephus granulatus Angelin, and Trinucleus coscinorrhinus 
Angelin. Some of these species are found at somewhat higher hori- 
zons, as high as the Middle Dicellograptus beds, but the majority of 
them are restricted to the Trinucleus coscinorrhinus zone. 

Conglomerate at Mystic, Que. 

Billings described a number of fossils from the township of Stan- 
bridge, Que. These were in all cases derived from boulders in 



170 bulletin: museum of comparative zoology. 

limestone conglomerates, which have a great development in that 
region. One of the best exposures is located on lot 22, concession VI 
of Stanbridge, about two miles north of Mystic. A long list of species 
from this locality, as determined by Dr. H. M. Ami, was published by 
Ells (Geol. suTv. Canada. Ann. rept., 1896, n.s., 7, pt. J, p. 127). 

Boulders of both Beekmantown and Normanskill age are found in 
this conglomerate, with the result, the fossils from these not having 
been kept separate, that considerable confusion has existed as to the 
composition of this fauna. The following trilobites were collected at 
this locality from a single boulder by Professor Schuchert and the 
writer: — 

Arthrorhachis galba (Billings), Remopleurides affinis Billings, Bathyu- 
rellus ezpansus Billings, Nilens scrutator Billings, A^. macrops Billings, 
Bronteopsis margtnata Ra^\Tiiond, Telephus sp. ind., Illaenus incerius 
Billings, /. simulator Billings, Acidiphorus scorpio7iis Raymond, 
" Bathyurus" breviceps Billings, Ectenonotus westoni (Billings), Kawina 
vukanus (Billings), Pliomerops hiliratus Raymond. 

Another boulder contained : — 

Arthrorhachis galba (Billings), Robergia breviceps Raymond, Homo- 
telus pelops (Billings). 

This fauna is of some interest, since it is the only trilobite fauna of 
Normanskill age yet found between Newfoundland and Virginia. 
Curiously, although the genera are those found in Newfoundland, 
many of the species are so far known from this locality' only. A 
positive correlation can not be made with present knowledge, but the 
presence of Ectenonotus, Bathyurellus, and Acidiphorus indicates that 
the fauna is of about the same age as that of divisions K and M of 
Newfoundland. 

Trilobites of the Lower Middle Ordovician in Virginia 

AND Tennessee. 

The Lenoir, Holston, Athens, and Ottosee are four formations about 
whose correlation there is still considerable of difference of opinion. 
The Lenoir is the oldest, and at many localities, the Holston rests upon 
it. In many other places, the Athens rests upon the Lenoir. The 
Ottosee at the typical locality rests upon the Holston, and the two 
usually are found in the same section, but at a few localities the 
Ottosee rests upon the Athens where no Holston is present. The 
Lenoir is always a dark-colored, usually an impure limestone. The 
Holston is nearh' always light-colored, generally coarse-grained, often 



RAYMOND: ORDOVICIAN TRILOBITES. 171 

a "marble," but never metamorphic. The Athens is a dark gray to 
black shale with, usually, a considerable number of layers of thinly 
bedded limestone in one or more zones. Graptolites are present, 
particularly in the lower part, and the fauna is that of the Normanskill, 
with Nemagraptus gracilis, Dicellograptus, etc. The Ottosee is typi- 
cally a greenish shale with more or less thinly bedded impure limestone 
of the same color. The fossils are chiefly from the limestone. Grapto- 
lites (Dendroidea) are present, but not common. 

The Lenoir. 

The fauna of the Lenoir is still \ ery imperfectly known, and 1 have 
not explored it very extensively for trilobites. In the typical region, 
in the vicinity of Knoxville, these fossils are not very common. Most 
of my material from the Lenoir has been obtained from three somewhat 
widely separated localities. 

South Knoxville, Tenn., and vicinity. 

Illaenus fieldi Raymond, Bumastus limhatus Raymond, B. lioderma 
Raymond, Encrinurus nodosarius Raymond, Pliomerops canadensis 
(Billings). 

Bluff City, Tenn. 

About 100 miles northeast of Knoxville. 

Robergia marginalis Raymond, Bathyurellus sp. ind., Homotelus 
obtus^is (Hall), H. laevis Raymond, Vogdesia hearsi RajTnond, Bumas- 
tus glohosv^ (Billings), B. aplatus Raymond, Acrolichas sp. ind., 
Glapkuru^ decipiens Raymond, Ceraurus granulosus Raymond and 
Barton, Ceraurus sp. ind., Sphaerexockus parvus Billings, Pterygome- 
topus gracilens Raymond. 

Catawba Valley, Va. 

About 230 miles northeast of Bluff City. 

Remopleurides canadensis Billings, Illaenus fieldi Raymond, /. lautus 
Raymond, /. valvulus Raymond, Bumastus lioderma Raymond, 
Homotelus obtusu^ (Hall), H. indentus Ra^'mond, Glaphurxis decipiens 
Raymond, Acrolichas minganensis (Billings), Ceraurus hudsoni Ray- 
mond, Nieszkowskia sp. ind., Pterygometopus annulafus Raymond. 

It will be noted that there is no species which is found at all three 



172 bulletin: museum of comparative zoology. 

localities, hut that two species, Illacnus ficldi and Bumastm lioderma, 
are found hoth at South Knoxville and the Catawba Valley. Homo- 
telus ohtusus and Glapkurus decipiens are common to Bluff City and 
the Catawba Valley, so that four of the species in the Virginian 
locality are found in one or the other of the more typical regions in 
Tennessee. 

The trilobites of the Lenoir, so far as known, have a decidedly 
Chazyan aspect. Remopleurides canadensis, Homotelus obtusus, Bu- 
viasius limbatus, B. globosus, B. aplahis, Vogdesia bearsi, Acrolichas 
minganensis, Ccraunis hudsoni, C. granidosus, Pliomerops canadensis, 
Sphaerexochis parvus, and Pterygomeiopns amndatus, nearly half the 
species, are found in the typical Chazy of the Champlain Valley. 
The other species, with three exceptions, belong to genera found in the 
Chazy, Glaphurus and Nieszkowskia being restricted to it in this 
country. The only unusual occurrences are species of Robergia, 
Encrinurus, and Ceraurinus and there is nothing very remarkable 
about their presence at this horizon. 

It would be unsafe, on the basis of trilobites alone, to try to corre- 
late the strata at any one of these three localities with any particular 
part of the typical Chaz\-. In that group trilobites are particularly 
common at two horizons, at the top of the Lower Chazy, and at the 
base of the Upper Chazy, the Middle Chazy having produced numer- 
ous trilobites at only one locality. 

Bumastm globosus, Sphaerexochus parvus, Pliomerops canadensis, 
and Pterygometops annulatus range through the three divisions of the 
typical Chazy. Homotelus ohtusus, Bumastus limbatus, Nieszkowskia, 
and Glaphurus belong to the Upper Chazy. Remopleurides canaden- 
sis, Vogdesia bearsi, Ccraurus hudsoni, and C. gramdosus are found in 
the Middle Chazy, and Acrolichas minganensis in the Middle and 
Upper. Bumastus aplatus has been found previously only at the top 
of the Lower Chazy. 

The general resemblance is, therefore, to the fauna of the Middle and 
L^pper Chazy. 

The Holston. 

The present state of knowledge of the Holston fauna is as inadequate 
as that of the Lenoir. The " Tennessee marbles " are usually extremely 
fossiliferous, but it is very difficult to obtain good specimens. 

The first three of the following lists, from the vicinity of Knoxville, 
Tenn., and the two localities in Bland County, Va., probably represent 
some of the more common species of the typical marble. The locality 



RAYMOND: ORDOVICIAN TRILOBITES. 173 

at the Thomas farm, near Blacksburg, Va., is in the limestone at the 
top of the Holston, near the contact with the Athens, and represents 
an association not found elsewhere. 

Vicinity of Knoxville, Tenn. 

This includes the Ross Republic and other quarries in South Knox- 
ville and the large quarry at Concord, Tenn. 

Eoharpes sp. ind., lUaenus fieldi Raymond, I. lautus Raymond, 
Bumashis longiops Raymond, B. liodcrma Raymond, B. dispa^sus 
Raymond (Fountain City, Tenn.). 

McNutt quarry, Sharon Springs, Bland Co., Va. 

Basilkus laevicidus Raymond, Hyhoaspis shuleri Raymond, Illaenus 
fieldi Raymond, Bumastus longiops Raymond, B. lioderma Raymond, 
Acrolichas minganensis (Billings), A. prominidus Raymond, Sphaerexo- 
chus discrepans Raymond. 

Hoge farm, near Bland, Va. 

Bronleopsis grcgaria Raymond, Homotelus indentus Raymond, 
Illaenus fieldi Raymond, Bumastus longiops Raymond, Cyheloides sp. 
ind., Ceraurus hudsoni Raymond, Sphaerexochus parvus Billings, 
Pterygometopus holstonensis Raymond. 

Thomas farm, three miles northeast of Blacksburg, Va. 

Arthrorhachis elspetki Raymond, Ampyx ca?/n/rw5 Raymond, Eoharpes 
sp. ind., Homotelus obtusus (Hall), Illaenus protuberans Raymond, 
Bumastus longiops Ra;vTnond, Nileus scrutator Billings, Bronteopsis 
gregaria Raymond, Calymene sp. ind., Onchaspis confraga Raymond, 
Ceraurus grayiulosus Ra\'mond and Barton, Sphaerexochus parvus Bil- 
lings, S. discrepans Raymond, Pterygometopus transsectus Raymond. 

Murat limestone, Lexington, Va. 
Bumastus longiops Raymond, B. lioderma Raymond. 

Comparison of faunas of Lenoir and Holston. 

If the fauna of the Lenoir near Knoxville be compared with that of 
the Holston of the same region, only one species, Bumastus lioderma, 
is found common to both. 



174 bulletin: museum of comparative zoology. 

If the first three Hsts combined be considered as affording a repre- 
sentative Holston fauna, and this list compared with a Hst of the 
Lenoir species, exchxding those recorded from the Catawba Valley in 
Va., all formations about which there is any doubt as to correlation 
will be excluded. In these two lists, three species are found, namely: — 
lUaenus ficldi, Bumastus liodcrma, and Sphaerexochus parvus. 

The Chazyan aspect of the Holston is well indicated by the presence 
of Eoharpes, Basilicus, H\'boaspis, Acrolichas minganensis, Sphaerexo- 
chvs parvus, Cybeloides, and Ceraurus hudsoni. Again, Middle and 
Upper Chazy are indicated. 

The peculiar mixed fauna of the Holston on the Thomas farm will b6 
mentioned again in the discussion of the fauna of the Athens. 

The strata in the Catawba Valley which 1 have here called Lenoir, 
might with equal propriety be termed Holston. Comparing the list 
of its trilobites with the restricted lists of Lenoir and Holston faunas, 
it will be noted that Illacnus lautus, Bumastiis liodcrma, Acrolichas 
7ni)uiancnsis and Ceraurus hudsoni occin* both in the Catawba Valley 
and in the Holston. On the other hand, Illaenus fieldi, Bumastvs 
lioderma, Homotelus obtusus and Glaphiirus decipiens are common to 
the strata in the Catawba Valley and the typical Lenoir. Whatever 
be the correct correlation, it is obvious that although the Lenoir and 
Holston faunas appear unlike in the typical region in eastern Ten- 
nessee, they really belong to the same stock. 

The Athens. 

Trilobites are found at several horizons in the Athens, and the 
species differ somewhat at different localities. The section at the 
typical locality, Athens, Tenn., is poor, because of lack of good 
exposures in the lower part. 

Athens, Tenn. 

Shale along railroad two miles northeast of Athens. Not far above 
base of the formation. 

Arthrorhachis elspethi Raymond, Trinucleus acervulosus Raymond, 
Lonchodomas poliius Raymond, Telephus troedssoni Ravnnond, Homo- 
telus sp. ind., Neviagraptus, Diccllograptus, etc. 

Thin-bedded limestone high in the Athens, near school house two 
miles northeast of Athens. 

Ampyx americanus Safford and Vogdes, Homotelus laevis Raymond, 
Isotelus sp. ind., Ceraurus sp. ind. 



RAYMOND: ORDOVICIAN TRILOBITES. 175 

Vicinity of Bullsgap, Tenn. 

Thin-bedded limestone at base of Athens between Bullsgap and 
Whitesboro. 

Ampyx amcricanus Safford and Vogdes, Homotchis lacvis Raymond, 
Bumastvs lioderma Raymond, Pterygomctopus onmilatus Raymond. 

Thin-bedded limestone high in Athens under railroad bridge over 
creek at Bullsgap. This is the type-locality for the first species. 

Ampyx americanus SafFord and Vogdes, Nileus scndator Billings. 

A limestone which appears to be the same as this is shown in a 
large cutting near Otes, about seven miles north of Bullsgap. It 
furnished : — 

Arthrorhachis elspethi Raymond, Ampyx americanus Safford and 
Vogdes, Raphiophorns sp. ind., Lonchodomas polifus Ra\Tnond, Nileus 
scndator Billings, Homoielus Jaevis Raymond, lUaenus fieldi Raymond, 
Bronteopsis gregaria Ra\Tnond, Ceraurus tenuicornis Raymond, 
Pterygomctopus annxdatus Raymond. 

Saltville, Va. 

In thin-bedded impure limestone and shale at base of Athens. 

Ampyx americanus Safford and Vogdes, Raphiophorns powelli Ray- 
mond, Robergia major Raymond, Telephus sp. ind., Triarthrus caeci- 
genus Raymond, Homotelus laevis Raymond, Nileus scrutator Billings. 

Blacksburg, Va. 

Trinuclcus accrvulosxis Raymond, Dionide holdoni Raymond, D. 
contrita Raymond, Triarthrus caecigenus Raymond. 

Catawba Valley, north of Salem, Va. 

In shale, associated with typical Normanskill graptolites. 

Raphiophorus powelli Raymond, Cryptolithus sp. ind., Robergia 
schlotheimi (Billings), Triarthrus caecigenus Raymond. 

In thin-bedded limestone which forms upper part of Athens. 

Raphiophorus pouielli Raymond, Ampyx americanus Safford and 
Vogdes. 

Lexington, Va. 

Base of the Liberty Hall limestone. 

Ampyx camurus Raymond, Remopleurides canadensis Billings, 
Homotelus obtusus (Hall), lUaenus fieldi Raymond, Bronteopsis gre- 



176 bulletin: museum of comparative zoology. 

garia Raymond, AcroHchas minganensis (Billings), Ceraurus granulo- 
sus Raymond and Barton, Sphaerexochus parims Billings. 

In the Athens at Athens, Tenn., at Saltville in southwestern Vir- 
ginia, and in the Catawba Valley of central Virginia, one finds trilo- 
bites with the graptolites of the Nemagraptus or Normanskill fauna, 
so that the comparison with the faunas in the Lower Dicellograptus 
beds of Sweden is particularly^ close. At these localities, the following 
species have been found directly associated with graptolites: — 

Arthrorhachis ehpethi Raymond, Trinucleus acervulosus Raymond, 
Lonchodomas poHtus Raymond, Raphiophorus poivelli Rajauond, 
Ampyx amcricanus Safford and Vogdes, Cryptolithus sp. ind., Rohergia 
schlothcimi (Billings), R. major Raymond, Telephus troedssoni Ray- 
mond, Telephus sp. ind., Triarthrus caecigenus Raymond, Nileus 
scrutator Billings, Homoielus laevis Raymond. 

These species are, therefore, undoubtedly of Normanskill age, and 
enough of them occur in the other faunas listed to indicate that all, 
except possibly that from Lexington, Va., are approximately con- 
temporaneous. The typical Normanskill in New York has not yet 
been found to carry trilobites in the same strata with the graptolites. 

The Athens contains trilobites of two categories, those adapted to a 
pelagic life, and those more at home in a benthonic habitat. It will be 
noted that with the exception of Hoviotelus laevis, all the species so, far 
found associated with graptolites are either blind or have very large 
eyes, either condition indicative of life in a region of feeble light, and 
most of them have broad flattened bodies and thin tests, some of them 
spinose. With few exceptions they appear to have been trilobites 
which were active swimmers, could float with little effort, and were 
particularly adapted to life on a muddy bottom, where, skimming 
along the surface of the soft ooze, they could gather decaying food 
inaccessible to heavier and truly benthonic creatures. 

In the more calcareous beds are found some of these same animals, 
but in addition, such "normal" types as Ceraurus, lUaenus, Homo- 
telus, and Pterygometopus. 

Comparison of the Athens with Ilolston and Lenoir faunas. 

Eight of the twenty-five species here listed as belonging to the 
Athens fauna are found in the Lenoir. These are : — 

Remopleurides canadensis Billings, Homotelus ohtusus (Hall), 
Illaenus fieldi Raymond, Bumastus lioderma Raymond, AcroHchas 
minganensis (Billings), Ceraurus granulosus Raymond and Barton, 
Sphaercxochus parvus Billings, Pterygometopus anmdatus Raymond. 



RAYMOND: ORDOVICIAN TRILOBITES. ' 177 

No one of the above trilobites is, however, found associated with 
graptoHtes, and hence they are not a part of the typical element of the 
Normanskill fauna. 

The number of species common to the Athens and the Holston is 
about the same. They are : — 

Arthrorhachis elspethi Raymond, Ampyx camunis Raymond, N ileus 
scrutator Bilhngs, Illaenus fieldi Raymond, Bumastus lioderma Ray- 
mond, Bronteoysis gregaria Raymond, Acrolichas minganensis (Bil- 
lings), Ceraurus gnmulosusKaymond and Barton, Sphaerexockus parvus 
Billings. 

It will be noted that five of these species are found in the Lenoir, 
Holston, and Athens, but that the other four are of the more strictly 
Normanskill type. The first three are, however, found in the Holston 
at only one locality, the Thomas farm near Blacksburg, Va., which, as 
has already been pointed out, has not a normal Holston fauna. 

Six of the species of the Athens are found in the Chazy of New York 
and Vermont: — 

Reniopleuridcs canadensis Billings, Homotelus obtusus (Hall), 
Acrolichas minganensis (Billings), Ceraurus granulosus Raymond and 
Barton, Sphaerexockus parvus Billings, Pterygometopus annulatus 
Raymond. 

All of these are also found in either the Lenoir or the Holston. 

The Trilobites of the Ottosee. 

Trilobites are not common in the typical Ottosee, in fact, they are 
practically absent from the formation in Tennessee, but are met with 
occasionally in Virginia. The list is, however, short. 

Speers Ferry, Va. 
Illaenus fieldi Raymond, Bumastus lioderma Raymond. 

Fugates Hill, north of Mendota, Va. 

Eoharpes sp. ind., Bronteopsis gregaria Raymond, Illaenus fieldi 
Raymond, Ceraurus hudsoni Ra^^mond. 

Saltville, Va. 

Lonchodomas politus Raymond, Pterygometopus annulatus Raymond. 

At Speers Ferry and Fugates Hill, the Ottosee overlies the Holston. 

At Saltville the Athens intervenes between the Holston and Ottosee. 



178 



bulletin: museum of comparative zoology, 



In all these localities the formation is much more calcareous than about 
Knoxville in Tennessee, where it is largely a green shale. As may be 
seen, the small fauna 'contains species found in the Holston and Athens 
chiefly, although some persist from the Lenoir. 



Coviparison of the Lower Middle Ordovician Trilobites of Tennessee 
and Virginia with those of other regions. 

Newfoundland. 

In a broad general way, there are great similarities between the 
faunas of the Lenoir, Holston, and Athens on the one hand, and of 
divisions 1, K, L, M, and N on the other. The Lenoir and Holston 
are limestones, as are 1, K, L, and M, whereas the Athens is composed 
of thinly bedded limestone and shale, a condition somewhat paralleled 
in N. In the limestones of both regions we find such genera as 11- 
laenus, Pliomerops, and Sphaexreochus, accompanied by other genera 
suggesting the normal Chazyan fauna, followed in both cases by an 
influx of so-called European genera, such as Raphiophorus, Ampyx, 
Robergia, Telephus, Bronteopsis, Nileus, etc. 

When detailed comparison is made, however, the differences are 
fully as great as the 1,500 miles which separate the two regions would 
lead us to expect. There are few species in common and my identifica- 
tion of these will probably be questioned. There are, however, many 
species in the Athens which are closely allied to forms in divisions 
M or N as shown in the following lists: — 

Athens. 
Arthrorhachis elspethi Raymond, 
Raphiophorus poioelli Raymond, 
Lonchodomas politus Raymond, 
Ampyx amerieamis Safford and Vogdes, 
A. cavutrns Raymond, 



Divisions M or N. 
A. galba (Billings). 
R. semicostatus (Billings). 
L. normalis (Billings). 
A. laeviusculus Billings. 



Remopleurides canadensis Billings, 
Robergia schhtheimi (Billings), 
R. major Raymond, 
Triarthnis caecigemis Raymond, 
Telephus troedssoni Raymond, 
T. sp. ind. 
Bronteopsis gregaria Raymond, 



R. panderi Billings. 
R. schlotheimi Billings. 

T. fischeri Billings. 
T. americanus Billings. 

B. gregaria Raymond. 
B. scotica Nicholson and 
Etheridge. 



RAYMOND: ORDOVICIAN TRILOBITES. 179 

Athens. Division M or N. 

Nilcus scrutator Billings, N. scrutator Billings. 

N. macrops Billings. 
Illaenu^ fieldi Raymond, /. fraternus Billings. 

Sphaerexochu^ parvus Billings, S. desertus (Billings). 

Striking differences are noted in the presence of Endymionia, 
Anisonotus, Bathyurellus, Niobe, and Megalaspis in Newfoundland, 
and the presence in Virginia and Tennessee of Dionide, Trinucleus, 
Homotelus, Bumastus, Ceraurus, and Pterygometopus. The simi- 
larities are, however, sufficient to indicate that the two faunas are 
nearly or quite contemporaneous, particularly when both faunas are 
compared with those of northern Europe. 

Girvan District, Scotland. 

The fauna of the Lenoir, Holston, and Athens compared with that 
of the Lower Middle Ordovician of the Girvan District, shows about 
the same similarities as were noted when the trilobites of Newfound- 
land were so compared on a previous page. The bulk of the allied 
species are found in the comparison of the faunas of the Athens and 
the Balclatchie, but it will be noted that Dionide occurs in the White- 
house Group in Scotland, above the Balclatchie and in strata referred 
by Reed to the lower part of the Caradoc. This genus is, however, 
known to range from top to bottom of the Ordovician. 

Lenoir or Holston. Stinchar limestone. 

Ampyx canmrus Raymond, A. cf. foveolatus Angelin. 

Illaenus fieldi Raymond, /. latus McCoy. 

/. portlocki Salter. 
Acrolichas minganensis Billings, A. hibernicus (Portlock). 

Encrinurus nodosarius Raymond, E. arenaceus Salter 

Calyviene sp. ind., C. cambrensis Salter. 

Ceraxirus gra7iulosus Kay mond and Barton, C. gelasinosus (Portlock). 
Sphaerexochus parvus Billings, S. balclatchiensis Reed. 

/S. discrepans Raymond, 

Pliomerops caiiadensis (Billings), Plioniera sp. ind. 

Pterygometopus anntdatiis Raymond, P. brongniarti (Portlock). 

Athens. Balclatchie group. 

Arthrorhachis elspethi Raymond, A. girvanensis Reed. 

Cryptolithus sp. ind., C. subradiatus (Reed). 



180 



bulletin: museum of comparative zoology. 



Athens. 

Lonchodomas politus Raymond, L. 

Ampyx amrricanus Safford and Vogdes, A. 

Triarthrus caccigcnus Raymond, T. 

Rohergia major Raymond, R. 
R. scholtheimi (Billings), 

Remopleurides canadensis Billings, R. 

T. troedssoni Raymond, T. 
T. sp. ind., 

Homotelus laevis Raymond, //. 

lUaemis fieldi Raymond, /. 

Bumastus lioderma Raymond, B. 

Bronteopsis gregaria Raymond, B. 

Acrolichas minganensis (Billings), A. 
Ceraurus granidosus Raymond and Barton, C. 

Sphaerexochiis parvus Billings, S. 

Pterygometopus anmdatus Raymond, P. 

P. 



Balclatchie group 

maccallumi (Salter) . 
austini Portlock. 
reedi Raymond. 
harrandei (Etheridge and 

Nicholson). 
girvancnsis Reed. 
Salter i Reed. 

grayae (Reed). 
peachi Reed. 
richardsoni (Reed). 
ardmillane7isis Reed. 
hihernicus (Portlock) . 
gelasinosus (Portlock). 
halclaichiensis Reed. 
hrongniarti (Portlock) . 
hunteri Reed. 



Athens. 
Dionide holdoni Raymond, 

D. contrita Raymond, 
Telephus troedssoni Raymond, 



Whitehouse group. 

D. lapworthi Etheridge and 

Nicholson. 
D. richardsoni Reed. 
T. fractus Barrande. 



EXPLANATION OF THE PLATES. 



PLATE 1. 



Raymond. — Ordovician Trilobites. 



PLATE 1. 

Fig. 1. Agnostus nudtts (Beyrich). A natural cast of the shield usually 
called the pygidium, showing the course of the suture. X 4. 

Fig. 2, 3. Arthrorhachis elspethi Raymond. A cephalon and pygidium from 
the typical locality. X 4. 

Fig. 4. Arthrorhachis elspethi Raymond. A pygidium from near Otes, 
Tenn., showing the "knees" for articulation. X 3^. 

Fig. 5, 6. Arthrorhachis longicollis Raymond. Cephalon and pygidium. 
X4. 

Fig. 7. Peronopsis munda Raymond. A pygidium. X 6. 

Fig. 8. Eoharpes uniserialis Raymond. A natural cast of the interior. 
X 2. 

Fig. 9. Eoharpes uniseriales Raymond. A specimen showing the interior 
of the test. X 2. 

Fig. 10, 11. Eoharpes fragilis Raymond. Two incomplete cephala. X 1|. 

Fig. 12, 13. Dionide jubata Raymond. Two nearly complete specimens, 
one lacking the genal spines. X 2. 

Fig. 14. Raphiophorus semicostatus (Billings). A nearly complete cephalon, 
retaining the spine. X 2f . 

Fig. 15. Raphiophorus semicostatus (Billings). A fairly complete but dis- 
torted specimen, lacking the spine. X 2|. 

Fig. 16. Dionide holdoni Raymond. Specimen with a damaged cephalon. 
X 2. * ' ' ' - 

Fig. 17. Dionide holdoni Raymond. A cephalon and part of thorax, retain- 
ing surface markings. X 2§. 

Fig. 18. Trinucleus acervulosus Raymond. The holotype. X 2. 



BULL. MUS. COMP. ZOOL. 



Raymond. Trilobites. Plate 1 




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PLATE 2. 



Raymond. — Ordovician Trilobitea. 



PLATE 2. 

Fig. 1. Raphiophorus powelli Raymond. The holotype, which lacks the 
anterior spine. X 2f . 

Fig. 2. Raphiophorus powelli Raymond. A specimen which has the pecuHar 
lateral lobes of an Ampyxina, only four segments in the thorax, and extra 
ribs on the pygidium. The axial lobe is damaged. X S?. 

Fig. 3. Ampyx americanus Safford and Vogdes. A nearly complete speci- 
men from the original locality, X 2. 

Fig. 4. Ampyx americanus Safford and Vogdes. A pygidium with ribs. 
X 1|. 

Fig. 5-7. Ampyx camurus Raymond. A cranidium and pygidium. X 2. 

Fig. 8-10. Lonchodomas politus Raymond. Two cranidia and a pygidium. 
X 2. 

Fig. 11. Lonchodomas suUaevis Raymond. The outline of a somewhat 
distorted specimen. X 1. 

Fig. 12. Lonchodomas suhlaevis Raymond. Part of a cranidium. X l\. 

Fig. 13. Endymionia schucherti Raymond. A very complete cranidium. 
X 2. 

Fig. 14. Crepicephalus sp. ind. Possibly the same species as the pygidium 
beside it. X 4. 

Fig. 15. Crepicephalus ceratopygoides Raymond. A somewhat damaged 
pygidium. X 1. 

Fig. 16. Triarthrus caecigenus Raymond. The holotype. X 3§. 

Fig. 17. Anisonotus glacialis (Billings). A specimen which lacks only the 
free cheeks. X 2|. 



BULL. MUS. COMP. ZOOL. 



Raymond. Trilobites. Plate 2 



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77 



PLATE 3. 



Raymond. — Ordovician Trilobiles. 



PLATE 3. 

Fig. 1, 2. Ischyrotoma twenhofeli Raymond. Dorsal and lateral views of the 
type. X 2. 

Fig. 3. Remopleurides rugicostatus Raymond. The thorax of an enrolled 
specimen. X 3. 

Fig. 4, 5. Remopleurides striatulus Walcott. The holotype and an hypo- 
stoma. X 1§. 

Fig. 6. Robergia major Raymond. An imperfect cranidium. X 2. 

Fig. 7. Robergia major Raymond. A free cheek. X 2f. 

Fig. 8. Robergia major Raymond. A pygidium from which the test of the 
pleural lobes has been removed, revealing the doublure. X 21. 

Fig. 9. Robergia major Raymond. A cranidium with part of an eye and 
free cheek. X 2f . 



Fig. 10. Robergia major Raymond. A part of the thorax. X 2 



Fig. 11. Robergia marginalis Raymond. An incomplete cranidium. Both 
palpebral lobes are damaged, and so appear much too small in the drawing. 



X 2^ 



3- 



Fig. 12. Bronteopsis gregaria Raymond. An incomplete cranidium. 
Glabella with unusually prominent median ridge. X 2. 

Fig. 13, 14. Bronteopsis gregaria Raymond. Two pygidia; the radial 
markings of that shown in Fig. 13 are unusual. X 2. 

Fig. 15, 16. Niobe lineolata Raymond. Two incomplete specimens; 
Fig. 15 is the holotype. X 2. 

Fig. 17. Nileus scrutator Billings. An hypostoma. X 2. 

Fig. 18. Bathyurellus abruptus Billings. An hypostoma, viewed from 
within. X 2f. 

Fig. 19. Bathyurellus fraternus Billings, A specimen from which the genal 
spines and other parts of the cephalon have been broken. X 1. 

Fig. 20. Niobe quadraticaudata (Billings). An hypostoma. X I5. 

Fig. 21. Xenostegium shepardi Raymond. The holotype. X 1. 

Fig. 22. Hemigyraspis mcconnelli Raymond. A pygidium. X 1. 



BULL. MUS. COMP. ZOOL. 



Raymond. Trilobites. Plate 3 



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PLATE 4. 



Baymond. — Ordovician Trilobitee. 



PLATE 4. 



Fig. 1. Homotelits elongatus Raymond. A much damaged specimen, X f . 

Fig. 2. Homotelus elongatus Raymond. Profile view of the cephalon and 
pygidium of an incomplete enrolled specimen. X §. 

Fig. 3. Homotelus elongatus Raymond. A normal specimen. X f . 

Fig. 4, 5. i/omoieitisiamitrws Raymond. Cranidium and pygidium. XI. 

Fig. 6. Homotelus indentus Raymond. An enlargement of a part of the 
test, to show the large shallow puncta. X 2§. 

Fig. 7, 8. Homotelus obtusus (Hall). A cranidium and pygidium. X 1. 

Fig. 9, 10. Edenaspis homalonotoides (Walcott). Pygidium and cranidium, 
drawn from plaster casts of the types. X 1. 

Fig. 11, 12. Illaenus lautus Raymond. Dorsal and outline profile views of a 
cranidium. X 2. 

Fig. 13, 14. Illaenus valvulus Raymond. A cranidium, and a pygidium to 
which one thoracic segment is attached. X 1§. 

Fig. 15, 16. Basilicus laeviculus Raymond. An incomplete free cheek and a 
pygidium, the latter drawn from an artificial cast of a natural mould. X |. 



BULL. MUS. COMP. ZOOL. 



Raymond. Trilobites. Plate 4 



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PLATE 6. 



RAYMOiND. — Ordovician Trilobitea. 



PLATE 5. 

Fig. 1, 2. Hyboaspis depressa Raymond. Two pygidia. X 1. 

Fig. 3, 4. Hyboaspis shuleri Raymond. A small and a large pygidium, 
X 1. 

Fig. 5. Homotelus catactus Raymond. An incomplete cranidium. X §. 

Fig. 6. Isotelus rejuvenis Raymond. The pygidium of the holotype. X f . 

Fig. 7. Homotelus indentus Raymond. A pygidium showing the peculiar 
indentation of the posterior end. X f . 

Fig. 8. Hyboaspis shuleri Raymond. Outline profile of the pygidium 
shown in Fig. 4. XI 



BULL. MUS. COMP. ZOOL. 



Raymond. Trilobites. Plate 5 



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PLATE 6. 



\ 



Raymond. — Ordovician Trilobites. 



PLATE 6. 

Fig. 1, 2. Homotelus gratiosus Raymond. An enrolled specimen which 
lacks the cranidium. X ^. 

Fig. 3. Homotelus ulrichi Raymond. The holotype. X about |. 

Fig. 4, 5. Homotelus ulrichi Raymond. Two views of an enrolled specimen, 
part of whose pygidium has been removed to show the doublure of the cephalon. 
X about f . 

Fig. 6. Harpes telleri Weller. Two cephala, viewed from the lower surface. 
X i 

Fig. 7. Onchometopus volborthi Schmidt. Specimen showing the narrow, 
hooked doublure and hypostoma. M. C. Z. 1,065. X about 1. 

Fig. 8. Vogdesia gigas Raymond. The holotype. X |. 

Fig. 9. Dionide contrita Raymond. The holotype. X about l-g-. 

Fig. 10. Niobe morrisi (Billings). A pygidium. X about |. 

Fig. 11. Megalaspis huttoni (Billings). A natural mould of a pygidium. 
X i 

Fig. 12. Plalylichas incoiisuetus Raymond. A cranidium. X about ^. 

Fig. 13. Niobe quadraiicaudata (Billings). A nearly complete specimen. 

Fig. 14. Niobe lindstroemi Schmidt. An incomplete specimen for compari- 
son with the preceding. M. C. Z. 1,055. X f . 

Fig. 15. Basilicus laeviculus Raymond. The posterior part of a cranidium. 
X g. 

Fig. 16. Illaenus viator Raj'-mond. A natural mould of a nearly complete 
specimen. X f. 

Fig. 17. Ulaenus viator Raymond. A partially enrolled specimen and its 
natural mould. X h. 



BULL. MUS. COMP. ZOOL. 



Raymond. Trilobites. Plate 6 




George Nelson, del. 



PLATE 7. 



Raymond. — Ordoviciaa TrilobitflS. 



PLATE 7. 

Fig. 1-4. Illaenus fieldi Raymond. Three cranidia, one of them in profile, 
.and a pygidium. X 1. 

Fig. 5. Illaenus alveatus Raymond. Profile of a cranidium. X 1. 

Mg. 6. Bumastus dispassus Raymond. The holotype. X 1. 

¥ig. 7. Bumastus comes Raymond. The holotype. X 1. 

Fig. 8, 9. Illaenus marginalis Raymond. Cranidium and pygidium. X 1. 

Fig. 10, 11. Bumastus lioderma Raymond. Two cranidia, one in profile, 
the other in dorsal aspect. X 1. 



I 



BULL. MUS. COMP. ZOOL. 



Raymond. Trilobites. Plate 7 





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PLATE 8. 



Raymond. — Ordovician Trilobitea. 



PLATE 8. 

Fig. 1, 2. lUaenus protuberans Raymond. Dorsal view of holotype, and 
outline profile of same. X 2. 

Fig. 3, 4. Bumastus aplatus Raymond. Cranidium and pygidium. X 1. 

Fig. 5, 6. Bimiashis holei Foerste. Profile and dorsal views of a complete 
specimen. X 1. 

Fig. 7, 8. Bumastus porrectus Raymond. Dorsal and profile views of a 
perfect specimen. X 1. 

Fig. 9. Cyphaspis slocomi Raymond. The holotype. X 4. 

Fig. 10. Hemiarges bartoni Raymond. An incomplete cranidium. X2f. 

Fig. 11, 12. Acrolichas prominulus Raymond. Dorsal view and outline 
profile of the type. XI. 

Fig. 13. Otichaspis confraga Raymond. A fragmentary- cranidium. X 2f . 

Fig. 14. Encrinurus nodosarius Raymond. The pygidium. X 2§. 

Fig. 15. Acidiphorus spijiifer Raymond. Lateral view of a pygidium lack- 
ing the terminal spine. X 2. 

Fig. 16. Acidiphorus scorpionis Raymond. Dorsal view of the pygidium. 
X 3i 

Fig. 17. Acidiphorus spiiiifer Raymond. Lateral view of a pjgidium. X 2. 

Fig. 18, 19. Bumastus longiops Raj^mond. A cranidium and pygidium. 
X 2. 

Fig. 20. Glaphurus decipiens Raymond. A nearly complete cranidium, 
X If. 

Fig. 21. Nieszkowskia sp. ind. An imperfect pygidium. X 1\. 

Fig. 22. Ceraurus angustus Raymond. The holotype. X 1§. 

Fig. 23. Ceraurus tenuicornis Raymond. The pygidium and part of a 
thoracic segment. X 2§. 



BULL. MUS. COMP. ZOOL. 



Raymond. Trilobites. Plate 8 




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PLATE 9. 



Raymond. — Ordovician TrilobileB. 



PLATE 9. 

Fig. 1. Ceraurus ruedemanni Raymond. A cranidium from the original 
locality. X 1. 

Fig. 2. Homoielus indentus Raymond. A pygidium. XI. 

Fig. 3, 4. Homotelus laevis Raymond. The cotypes. X 1. 

Fig. 5, 6. Hadrohybus dunbari Raymond. Dorsal and profile views of the 
type. X 1. 

Fig. 7. Ectenaspis beckeri (Slocom). The holotype. The eyes are im- 
known, and the restoration of them is wholly conjectural. X 1. 

Fig. 8. Cybeloides iowensis Slocom. A pygidium. X 3. 



BULL. MUS. COMP. ZOOL. 



Raymond. Trilobites. Plate 9 



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Elvira Wood, Hel. 



PLATE 10. 



Raymond. — Ordovician Trilobites. 



PLATE 10. 

Fig. 1. Sphaerexochus romingeri Hall. A nearly entire, enrolled specimen. 
X 2. 

Fig. 2. Sphaerexochus romingeri Hall. Anterior view of the cephalon, show- 
ing the hypostoma and its relation to the cheeks. X 2. 

Fig. 3, 4. Sphaerexochv^ discrepans Raymond. Two glabellae. X 2. 

Fig. 5. Sphaerexochus parvus Billings. A pygidium. X 6. 

Fig. 6, 7. Pliomerops hilirata Raymond. Dorsal and anterior views of the 
cephalon. X 2. 

Fig. 8. Nieszkowskia excehus Raymond. A drawing of an artificial cast 
made from the natural mould which is the type. X 1. 

Fig. 9. Pterygometopus holstonensis Raymond. An incomplete cranidium, 
the holotype. X 2. 

Fig. 10. Pterygometopus holstonensis Raymond. A small glabella with a 
palpebral lobe. X If. 

Fig. 11. Pterygometopus holstonensis Raymond. A pygidium. X 2. 

Fig. 12. Pterygometopus transsectus Raj^mond. The holotype. X 3|. 

Fig. 13. Perischoclonus capitalis Raymond. The holotype. X 2. 

Fig. 14. Pliomerops trouti Raymond. The holotype. X 1^. 

Fig. 15. Pliomerops nevadensis (Walcott). A very fragmentary cranidium. 

XI. 

Fig. 16. Pterygometopus annulatus Raymond. A cephalon. X 1|. 

Fig. 17. Pterygometopv^annulat^isRaymond. A pygidium. X 2. 

Fig. 18. Pterygometopus gracilens Raymond. The holotype. X 2. 



BULL. MUS. COMP. ZOOL. 



Raymond. Trilobites. Plate 10 



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MAY 28 1925 



Bulletin of the Museum of Comparative Zoology 
AT HARVARD COLLEGE. 
Vol. LXVII. No. 2. 



THE SYSTEMATIC POSITION OF PALAEOSPIZA BELLA 
ALLEN, WITH OBSERVATIONS ON OTHER FOSSIL BIRDS. 



By Alexander Wetmore. 



With Four Plates. 



CAMBRIDGE, MASS., U.S.A.: 

PRINTED FOR THE MUSEUM. 

May, 192.5. 



\ 



No. 2. — The Systematic Position of Palaeospiza bella Allen, with 
Observations on other Fossil Birds. 

By Alexander Wetmore. 

Introduction. 

In the year 1877 Mr. S. H. Scudder obtained near Florissant, Colo- 
rado, a slab containing the fossilized remains of a passeriform bird of 
small size preserved almost entire. The specimen was placed in the 
hands of Dr. J. A. Allen, then at the Museum of Comparative Zoology, 
for study, and was described by Allen as Palaeospiza bella (Bull. U. S. 
geol. geog. surv. terr., 3 May, 1878, 4, p. 443-444, pi. 1, fig. 1). The 
type was deposited for many years in the Boston Society of Natural 
History, but recently has been transferred to the Museum of Compara- 
tive Zoology, where it has been mounted in a plaque and placed on 
exhibition. Thus far our knowledge of Palaeospiza has been based on 
the original description and it has seemed advisable to submit the type 
to a second critical examination in the light of advance in knowledge 
in the nearly fifty years that have elapsed since its discovery. Through 
the kind cooperation of the authorities of the Museum of Comparative 
Zoology, the type of Palaeospiza was forwarded to the U. S. National 
Museum at AVashington, where it has been compared with a large 
number of recent birds. The writer is deeply indebted to the Museum 
for the privilege of this examination. 

In the original description the strata from which the type of Palaeo- 
spiza came were called the insect-bearing shales of Florissant, while in 
the list of fossil birds in the third edition of the A. O. U. Check-List, 
published in 1910 (p. 392), they are recorded as the Amyzon Shales. 
In more modern nomenclature these deposits are known as the Floris- 
sant lake beds, famous for the large numbers of beautifully preserved 
plants and insects that they have yielded during a period of fifty years. 
For details regarding the beds in question, I am indebted to a recent 
paper by Dr. F. H. Knowlton on the fossil plants of this region, ^ in 
which is given, in the introduction, a resume of the occurrence of these 
deposits. Fossils in these strata are believed to have been laid down 
in the shallow waters of a small lake with ail irregular shore line, five 

^ A Review of the Fossil Plants in the United States National Museum from the Florissant 
Lake Beds at Florissant, Colorado, with Descriptions of new Species and List of Type-Speci- 
mens. Proc. U. S. N. M., 24 November, 1916, 51, p. 241-297, 16 plates. 



184 bulletin: museum of comparative zoology. 

miles long and a mile wide. The preserved material is supposed to 
have been buried in volcanic ash, sifted over the country during 
repeated eruptions, and in mud and sand washed in by rains. As the 
Florissant beds lie isolated from other sedimentary rock, in deposits 
of granite, their geologic age must be determined from palaeontological 
evidence alone. Dr. A. C. Peale, who visited the area in 1873, and 
gave the first account of its geology, considered them as Pliocene, but 
Lesquereux, who studied the plants, at first believed them to be 
upper Miocene, but later, with Cope, called them lower Miocene, or 
Oligocene, a position assigned them in most current text-books. 
Further study, particularly of the plants, has indicated that Les- 
quereux's original assignment was correct, so that Knowlton, the most 
recent authority to write on the subject, states {I.e., p. 244) that 
"While it is improbable that the final word has been said regarding 
the exact stratigraphic position of these beds, until conclusive evi- 
dence to the contrary has been presented the Florissant plant-bearing 
beds may be regarded as upper Miocene." 

Though plant and insect remains occur in these beds in abundant 
profusion, avian fossils have remained rare. Palacospiza bella, the 
first bird to be described from them, was followed by Charadrius shep- 
pardianvs Cope (Bull. U. S. geol. geogr. surv. terr., 11 February, 1881, 
6, p. 83), discovered by Dr. G. Hambach and named for Edwin Shep- 
pard, of Philadelphia, according to Cope "an excellent ornithologist 
and skillful artist." Dr. Knowlton (Proc. U. S. N. M., 1916, 51, 
p. 245) has called attention to the curious fact that the type of Fonti- 
nalis prwtlna Lesquereux (Rept. U. S. geol. surv. terr., 1883, 8, p. 135, 
pi. 21, fig. 9), named as a species of moss, is in reality a section of a 
feather. The A. O. U. Code seems to make no provision for such 
cases, but in the International Code it is stated "if, however, an 
organism is transferred from the vegetable to the animal kingdom, its 
botanical names are to be accepted in zoological nomenclature with 
their original botanical status." 

The type in question must be considered as a definitely named fossil 
bird though there is little or no hope that a proper relationship may be 
assigned it. 

As Fontinalis does not appear to be preoccupied in zoology, Fo7i- 
tinalis pristina must be anchored as another weathered derelict in the 
sad haven of inccrtae sedis, at the close of our check-list of fossils. 
Both genus and species will have Lesquereux as authority. 

Additional fossil remains from the Florissant have been described 
(but not named) by Shufeldt (Proc. U. S. N. M., 15 August, 1917, 53, 



WETMORE: systematic position of PALAEOSPIZA BELLA. 185 

p. 453-455, 2 pis.), who gave an account of two small slabs containing 
impressions of bird bones, secured by Prof. I. E. Cutler, of the Uni- 
\ersity of Den^•er. In the present connection I ha\e examined these 
specimens and find that they comprise two passeriform species, one 
represented by an impression of the pelvic and caudal region, and the 
other, somewhat larger, by the tarsus, foot, and tibio-tarsus. These 
are too incomplete to warrant further study at present. 

Feather remains (in addition to the type of FontinaUs pristma) 
appear fairly numerous, as there are five slabs bearing impressions of 
this character in the palaeontological collections in the U. S. N. M. 
Some of these, together with some additional fossil feathers in the 
same deposits, received from Prof. T. D. A. Cockerell, have been 
described and figured (but not named) by Dr. R. W. Shufeldt (Journ. 
geol., 1913, 21, p. 631-634, 2 figs.). 

Description of Palaeospiza bella. 

Dr. Allen in his original description says that Palaeospiza represents 
" a high ornithic type, probably referable to the Oscine division of the 
Passeres. . . . The absence of the bill renders it impossible to assign 
the species to any particular family, but the fossil on the whole gives 
the impression of Fringilline affinities." The species has been carried 
in the list of fossil birds in the A. O. U. Check-List (third edition, 1910, 
p. 392) as a questionable member of the Fringillidae, and has usually 
been considered a finch, in part because of the derivation and form 
of the generic name. 

On the same plaque as the type is mounted an impression of the 
end of a wing and the tip of a tail of a bii'd which belongs to another 
specimen, and has no connection with Palaeospiza. This represents 
the distal end of the primaries of a bird with a broad, rounded wing tip, 
with the shafts of the feathers somewhat curved. The distal end of 
the rectrices appear to have been graduated with strong heavy shafts. 
The general impression is that these are similar to the wing and tail of a 
woodpecker, or a dendrocolaptid, but it is of course, impossible to 
determine their actual affinity. 

As has been stated the type of Palaeospiza bella consists of a more or 
less complete bird, which has been flattened by pressure. The slab 
in which it is preserved has been split and separated, so that two sil- 
houettes are presented (Plates 1-4), with part of the bones of the fossil 
adherent in one, and a part in the other. The impression gi\'en is 
that the bird originally lay on its breast, with wings folded at the sides 



186 bulletin: museum of comparative zoology. 

and feet and neck extended. The fossil is preserved as a thin plate 
impressed on two slabs of grayish stone which, with the fossil itself is 
soft and friable. In fact, parts of the plate with several fragments of 
bones have been lost. As the bird is now mounted, the left-hand por- 
tion is impressed and the right-hand one elevated and rounded. In 
color, the bones are dull, yellowish brown, while the feather impressions 
are blackish. Certain rounded masses, dull brownish in color, in the 
thoracic region and near parts of the humeri may represent the fossil- 
ized remains of dried flesh. 

The drawing, executed by Mr. J. H. Blake, that accompanied the 
original description, is excellent in its fidelity to outline, proportion, 
conformation and position of parts, but has the detail of the feathers 
and various parts considerably exaggerated, as the fossil is much less 
sharply defined and distinct than one might suppose from studying 
the original cut. 

Skull. — The cast containing the anterior portion of the head has 
been broken away and lost at the line of the pars plana, or perhaps just 
behind that point. The remaining impression of the skull is present 
only on the left-hand slab, as on the opposite plate of stone the fossil 
has been chipped off in an irregular line that passes through the level 
of the shoulders. On this right-hand slab, however, there is a faint 
depression in the matrix that outlines the former resting place of the 
head. In this impression may be traced an indistinct line that indi- 
cates a cranium and a forehead that slopes down to a faintly indicated 
bill, that may or may not have been flattened. It is unfortunate that 
the actual bone is not present as it would afford important characters. 
On the left-hand slab, where the fossil remains, the outline of the 
cranium is seen to be low and flattened with a low, sloping forehead. 
A somewhat triangular impression above, that corresponds to the high, 
distorted concavity of the opposite slabs, represents former feathers or 
skin; it leads to conjecture regarding a possible crest. The upper 
and lower outlines of the cranium are marked by broken bits of bone 
that scribe a distinct but irregular line. Angular impressions in the 
lower anterior angle of the orbit may indicate sclerotic plates from the 
eye, and perhaps remains of palatal or ethmoidal elements. The 
posterior half of the ramus of the lower jaw is fairly distinct ; it appears 
narrow with indication of a foramen. The processus angularis pos- 
terior was prolonged slightly beyond the articulation, and then was 
obliquely truncated. The external ear opening seems to have been 
small. 

Neck. — The curved line of the cervical vertebrae is distinct, but the 



WETMORE: systematic position of PALAEOSPIZA BELLA. 187 

impression is so blurred that individual bones may be made out in 
only a few cases. The total length is moderate as in most small birds. 

Shoulder girdle. — The furculum is short and its fork broad, with a 
slightly projecting, posterior point at the median symphysis as the only 
certain indication of a hypocleideum. The coracoid, which is badly 
crushed, apparently was quite strong, with a considerable expansion 
at the lower end. 

Sfcnium. — The breast bone is very indistinct. A faint outline 
within the arms of the furculum may indicate the fork of a strong spina 
externa. The articular points with the lower end of the coracoid are 
indicated, a slight projection at the lower end of the bone may repre- 
sent a part of the carina, and an imperfect plate beside it a fragment of 
the xiphoid extremity. On this latter part there is indicated a single 
notch. The region is not well enough preserved to show certainly 
vvhether one or two notches were present on either side. 

Fore-limb. — Both humeri are present though considerably crushed. 
They appear strong and heavy, with the crista superior shortened so 
that it does not extend distally beyond the level of the plate that, on 
the opposite side, forms the boundary of the fossa subtrochanterica. 





Fig. 1. — Palaeospiza bella. 
Anterior view of distal end 
of left humerus, X4. 



Fig. 2. — Palaeospiza bella. 
Posterior view of distal 
end of right humerus, X4. 



The entire head of the humerus thus appears shortened. The upper 
end of the shaft is distinctly angled, while the lower portion is rounded 
as is usual. The ectepicondylar process (Fig. 1) is well developed and 
is fairly high on the shaft. It is not produced to the extent found in 
the finches or higher oscines, nor does it seem to be divided at the tip. 



188 bulletin: museum of comparative zoology. 

Pressure against an underlying Ijone has forced it backward, but its 
form is easily evident in spite of this distortion from position. On the 
opposite side (Fig. 2) the epitrochlea is prominent and is produced 
distally as a strong process beyond the general level of the outer end of 
the bone. The ulnar trochlea is narrow but well developed. Its 
axis is sigmoid, and it extends across to the epitrochlea in a direct line, 
so that, viewed from above, its distal margin is straight, as in all oscine 
birds that I have examined. In all the lower Passeriformes, the 
Eurylaemidae (broad bills), the Mesomyodi (the tracheophones, fly- 
catchers, cotingas, etc.), and the Pseudoscines (the lyre-bird), the ulnar 
trochlea has the external margin declivous, sloping down to join the 
epitrochlea, so that the trochlea projects as a distinct knob. The 
character seems to be one of importance in separating the higher and 
the lower Passeriformes. 

Above the ulnar trochlea there is evident the depression of the 
brachialis inferior, with a sharply raised external border, and a flat- 
tened surface for the insertion of the pronator brevis and longus. 
This inner face of the lower end of the humerus is flattened, so that it 
appears nearly plane. 

The radial trochlea is well developed though not large, is slightly 
concave on its inner face, and at its upper end meets the shaft at an 
abrupt angle. The intertrochlear sulcus is narrowed. 

The ulna is strong, with a fairly prominent olecranal process. Other 
details are lacking. The radius is well outlined, and, like the ulna, is 
extraordinarily large and heavy for the size of the bird. The radius, 
while about as long as the radius in the cedar waxwing, is twice as thick 
as in that species. 

The metacarpus is of the usual passeriform type, with a distinct 
tuberositas musculis that extends from the second metacarpal across 
the metacarpal fissure. The tuberculum ulnare appears longer than 
the tuberculum radiale, but the degree of difference in length between 
the two may not be made out. The pollex is very faintly indicated. 
The first phalanx beyond the metacarpal appears relatively shortened, 
and the second considerably elongated. There is no indication that 
wing claws were present. 

The humerus and the fore-arm are more nearly equal in length than 
in usual perching birds, as the fore-arm seems only slightly longer 
than the humerus. The hand too is elongated, and from its indistinct 
impression appears nearly, and perhaps actually, as long as the fore- 
arm. 

The outstanding features of the wing are the shortened fore-arm. 



WETMORE: systematic position of PALAEOSPIZA BELLA. 189 

the elongated distal phalanx of the second digit, and the remarkable 
strength of radius and ulna. 

Ribs.— A few of the posterior ribs show as hair lines below the 
sternum at one side. Apparently only the sternal segments are pre- 
served. 

Pelvis. — The pelvic region is too indistinct to offer details of im- 
portance. The sacrum is outlined with some definiteness but is con- 
siderably crushed. There is faint presentation of the ilium. 

Posterior limb. — The femur, which is shown in outline on the left 
half of the fossil, seems to have been comparatively long and strong. 
The outer face, apparently the one presented, was straight as there is 
no indication of axial flexure. The tibio-tarsus appears of moderate 
length in comparison with the femur. It was fairly strong, but is so 
crushed that the terminal processes are only faintly evident. The 
tarsus seems to have been remarkably small and slender. There is 
some indication, particularly on the left-hand slab, that the acrotar- 
sium was smooth and was of the acutiplantar form usual in typical 
oscine birds (except the Alaudidae, where it is latiplantar). No scutel- 
lation is actually evident on the anterior face, though there is faint 
indication that the tarsal sheath of this portion may have been divided. 
Both tarsi are somewhat broken at the lower end which gives them the 
appearance of being slightly less in length than is really the case. 

The toes, four in number, comparatixely long with long, slender 
claws, are arranged with three projecting toward the front and one 
behind, in the typical passeriform manner. The third toe, the middle 
anterior one, is slightly longer than the others, while the second and 
fourth on either side are apparently al)out equal in length. The 
hind toe, while long, is decidedly shorter than the other three. 

Feathers. — On one or the other of the hahes of the cast wing and tail 
feathers, with a few on flank, neck, and breast, are represented by a 
blackish discoloration, that in the case of the larger feathers is lined by 
impressions made by the heavy shafts. The tail seems to have been 
broad and perhaps rounded. The two median rectrices project eight 
millimeters bevond the others; the lateral feathers, clearlv visible on 
the right-hand side, decrease gradually in length toward the outside. 
The shafts of six feathers are faintly impressed on this right side, indi- 
cating a tail of at least twelve rectrices. 

The wings are folded in against the body and cannot be seen dis- 
tinctly. They are long, as in their folded condition the distal end 
extends well past the base of the tail. It appears that they were of 
fairlv broad area; details of their structure mav not be determined. 



190 bulletin: museum of comparative zoology. 

Measurements. — As most of the bones in Palaeospiza bella are 
somewhat crushed, or even broken, lengths of the various parts may be 
determined only approximately All measurements given below have 
been taken carefully by means of dividers. 

Length of specimen from point of shoulder to approximate end of 

pope's nose 66.5 mm. 

Length of furcuhim 14.5 " 

" " humerus 23.4 " 

Breadth of humerus at distal end 5.5 " 

" " shaft of humerus near center 3.0 " 

Length of ulna 22.0 " 

" " hand 24.5 " 

" " metacarpus 12.6 " 

" " distal phalanx of second digit 6.0 " 

" " femur 18.0 " 

" " tibio-tarsus 27.0 " 

" " tarso-metatarsus 17.5 " 

" " middle toe and claw (measured in two segments) 15.6 " 

" " impression of longest rectrix 58.5 " 

Approximate length of wing 80.0 " 

Systematic Position. 

Allocation of Palaeospiza hella in our scheme of avian classification 
is difficult, as the greater part of the head is missing, and the fossil, 
though handsome to look upon, lacks definite impressions of many of 
the points used in deciding relationship. It appears that Palaeospiza 
hclla is not directly related to any of our modern groups, but must 
stand in a separate category to be known as the family 

Palaeospizidae. 

Type. — Palaeospiza bella Allen. 

Diagnosis. — Bones of the wing strong and heavy, with humerus only 
slightly shorter than fore-arm and hand elongated; head of humerus 
shortened, distal end with ulnar trochlea not produced as a knob 
beyond level of epitrochlea (oscinine in form) ; anterior face of lower 
end of humerus much flattened ; ectepicondylar process relatively high 
on shaft, distal phalanx of second digit elongated, radius and ulna 
very strong; tarsus small and slender, toes long, with long slender 
claws; third toe longest, second and fourth about equal, the first 
somewhat shorter than the other three. 



WETMORE: systematic position of PALAEOSPIZA BELLA. 191 

Relationships. — In its large wings and small feet Palaeospiza bella 
suggests some of the flycatchers or cotingas. It seems particularly to 
have had very long wings, longer than in the average perching bird. 
In size it appears about equal to the cedar waxwing {Bombycilla cedro- 
rum). The form of the foot, with the general sum of the appearance 
of the bird, indicate that Palaeospiza is a member of the great order of 
Passeriformes. Further, the form of the ulnar trochlea of the humerus 
definitely places it in the superfamily Oscines as defined by Ridgway. 
It is undoubtedly low in position in that group; and it has been indi- 
cated that it gives certain suggestions of approach to some members of 
the superfamily Mesomyodi. 

The family Palaeospizidae, therefore, may be placed in the Oscines 
immediately above the Alaudidae, which family in form of the tarsus 
differs from all other Passeriformes, and is located at the base of the 
oscinine group. Palaeospiza has no direct relationship to the larks, 
but rather occupies a somewhat connecting position between the 
Mesomyodi and the acutiplantar Oscines. 

The Palaeospizidae at present includes a single species, Palaeospiza 
bella. 

The Status of Palaeospiza il\tcheri Shufeldt. 

In connection with a study of Palaeospiza bella Allen it has been 
necessary to examine a second fossil, one named by Dr. Shufeldt 
(Bull. Amer. mus. nat. hist., 4 August, 1913, 32, p. 301, pi. 55, fig. 28) 
Palaeospiza hatcheri, secured near Long Island, Kansas, from beds of 
doubtful position sometimes called lower Pliocene, but at present 
usually considered Miocene. In the original description this form was 
characterized as follows : — " This is the superior mandible of a small 
finch . . . and it would be difficult to distinguish the same from the 
same part of the skull in many a small existing species of that group, 
the size of a Junco for example, or a Spinus. The species may, quite 
possibly, still be in existence or its genus may; in any event, this 
material is not sufficiently extensive for a scientific reference. I have 
not seen the material upon which Allen based his Palaeospiza from the 
Amyzon Shales of Colorado (Eocene ?). Should it be found to belong 
in that genus, it may, for the sake of designation and record, be sub- 
sequently known as P. hatcheri for its discoverer. ..." 

The type of Palaeospiza hatcheri (U. S. N. M. Cat. 6,647) is an entire 
upper mandible forward of its junctions with the frontal and the 
anterior end of the jugals (Fig. 3, 4). It was secured with broken 



192 



bulletin: museum of comparative zoology. 



fragments of other small \'ertebrates by J. B. Hatcher in 1884. It 
requires but a glance to determine that this specimen comes from a 
typical finch (Fringillidae), and as such has only remote connection 
with the type of the genus Palaeospiza. Though imperfect, the type 
of hatcheri is sufficiently complete to exhibit pertinent characters. 
On careful comparison it is found to differ so from modern finches as 
to necessitate the erection for it of a distinct group which may be called 



Palaeostruthus, gen. no v. 

Characters.— '^imWuY to Pipilo Vieillot (Analyse, ISIG, p. 32. 
Type.— Fringilla erythrophthalma Linne), but premaxilla more acute at 
point, lateral margins more concave; nasal process of premaxilla of 
uniform width throughout, not expanding in anterior half toward its 
union with premaxilla; maxilla not produced posteriorly behind 
union with maxillary process of nasal; maxillary process of nasal 
not decidedly expanded at lower end where it joins maxilla. 

Type.— Palaeospiza hatcheri Shufeldt, which will now stand as 
Palaeostruthus hatcheri (Shufeldt). 





Fig. 3. — Palaeostruthus 
hatcheri. Type. Dor- 
sal view. X2. 



KiG. 4. — Palaeostruthus 
hatcheri. Lateral 
view, X2. 



Remarks. 

Somewhat extended comparisons of Palaeostndhns hatcheri with 
skulls of a large number of species of finches from the New and Old 
Worlds have placed it in the supergeneric group termed by Ridgway 
the Zonotrichiae, a group that contains the towhees, juncos, white- 
throats, song sparrows, chipping sparrows, and the host of allied 
species that today comprise a majority of our native sparrows. 

In outline the premaxilla of hatcheri is very near to Ammodramus 
saramiarwn, as it has the same acute point, concavity of the lateral 



WETMORE: systematic position of PALAEOSPIZA BELLA. 193 

margins, and pronounced posterior broadening of that species. The 
arrangement of the maxillary in Pahieostruthus is, however, distinctly 
different, and places it in another group. It seems allied to Pipilo, 
particularly to the forms in which the males are largely black and white 
differing from these in the points outlined in the diagnosis. In size 
Falarostruthiis hatrhcri is smaller as it seems to have the approximate 
dimensions of the green-tailed towhee, Obcrholscria chlorura. 

It will stand in the Zonotrichiae adjacent to the genus Pipilo. 

Following are pertinent measurements of the type of Pahieostruthus 
hatcheri: — 

Total length from tip of premaxilla to posterior margin of nasal 

opening 10.0 mm. 

Greatest breadth through maxillae 6.3 

Greatest horizontal depth from bridge of culmen to maxilla 3.5 " 

Length of external narial opening 4.0 " 

Depth of external narial opening 2.0 



EXPLANATION OF THE PLATES. 



PLATE 1. 



Wetmore. — Systematic Position of Palaeospiza bella. 



PLATE 1. 

Palaeospiza bella. View of portion of type specimen with part of head, 
life size. 



BULL. MUS. COMP. ZOOL. 



Wetmore. Palaeospiza. Plate 1 




PLATE 2. 



Wetmore. — Systematic Position of Palaeospiza bella. 



PLATE 2. 

Palaeospiza bella. Same as Plate 1, retouched to bring out detail of bones, 
life size. 



BULL. MUS. COMP. ZOOL. 



Wetmore. Palaeospiza. Plate 2 




PLATE 3. 



Wetmore. — Systematic Position of Palaeospiza bella. 



PLATE 3. 

Palaeospiza bella. View of half of type opposite to that shown in Plate 1, 
life size. 



BULL. MUS. COMP ZOOL. 



Wetmore. Palaeospiza. Plate 3 




PLATE 4. 



Wetmore. — Systematic Position of Palaeospiza bella. 



PLATE 4. 

Palaeospiza bella. Same as Plate 3, retouched to bring out detail of bones, 
life size. 



BULL. MUS. COMP. ZOOL. 



Wetmore. Palaeospiza. Plate 4 




No. 3. — The 11 cur II Bryant Types of Birds. 
By Outram Bangs and Thomas E. Penard. 

After the death of Dr. Henry Bryant, in 1867, his collection of 
birds remained in the possession of his son, Dr. W. S. Bryant, and 
finally was presented by Dr. Bryant's heirs to the Museum of Com- 
parative Zoology. In the meantime, Mrs. Henry Bryant had given 
some specimens to the U. S. N. M. and to several foreign institutions, 
and in that way a number of the Bryant types passed into other hands. 

The birds collected by Robert Swift and George Latimer in Porto 
Rico, and described by Dr. Bryant, originally went to the V. S. N. M., 
but subsequently many were either donated to or exchanged with 
home and foreign museums or collectors, and among that number 
were several of the types, including those of Todus hypochondrianis, 
Psittacus coUarius hahame7isis, Saurofhera ricillotii rufcsccns, Tiirdus 
ardosiaccus porforiccnsis, Tyrannus antillarum, Mimus polyglottus 
portoriccnsis, and Tanagra domiiiiccusis. Fortunately two of these, 
Tyrannus antillarum and Tanagra dominicensis, became the property 
of Dr. Bryant and are now in the collection of the M. C. Z. 

Altogether Dr. Bryant proposed six new genera and subgenera, 
described twenty-eight new species and subspecies, and was responsible 
for one nomcn nudum. 

An account of Dr. Bryant's life and scientific career, prepared by a 
Committee consisting of S. L. Abbot, J. C. White, and J. E. Cabot, 
appointed at the meeting of the Boston Society of Natural History, on 
February 20, 1867, of which Society Dr. Bryant was an active member, 
was pul)lished in the Proceedings of that Society (Proc. Boston soc. nat. 
hist., 1867, 11, p. 205-215) shortly after his death which took place 
at Araceibo, Porto Rico, in February, 1867, while on a collecting trip. 

During his life Dr. Bryant made a number of expeditions for 
scientific research, visiting California, Grand Manan, Florida (several 
times), Bahamas (several trips), Canada, and Labrador, North Caro- 
lina, Cuba, Jamaica, and Porto Rico; as a result of these he pub- 
lished a number of papers dealing with the birds he collected or 
observed. 

He made many donations of natural history specimens to the Boston 
Society of Natural History, a partial list of which has been published 
in the report of the committee referred to abo\'e. The most important 
of these was the magnificent Lafresnaye collection of birds, containing 



198 bulletin: museum of comparative zoology. 

nearly nine thousand specimens, which he had purchased in France 
upon the death of the noted French ornithologist. This, one of the 
finest collections of that time, brought to this countr\- not only most 
of the types of the species (mostly American) described by Lafresnaye, 
but also those of many other naturalists whose types had found their 
way into Lafresnaye's possession. This valuable collection has since 
been transferred to the M. C. Z. 

The Committee's report also contained a list of communications and 
papers read by Br\ant at the meetings of the Society.. Several minor 
articles or communications having escaped the notice of that Com- 
mittee, we have included in this paper a list of his ornithological 
writings, in so far as these ha\e come within our ken in our search 
for Bryant material. 

List of the orxithological avritings of Henry Bryant. 

[Report on a volume of the Naturalist's library, on gallinaceous 
birds]. 

Proc. Boston soc. nat. hist., 1841, 1, p. 19. 

[Report on a parrot presented by Mr. Teschemacher to the Boston 
Society of Natural History]. 

Proc. Boston soc. nat. hist., 1842, 1, p. 60. 

Premier essai d'une determination nouvelle de ce qu'on a nomme 
jusqu'a present corps strie chez les oiseaux (Extrait d'une Note de 
MM. Bryant et Pappenheim). 

Compt. rend. Acad. sci. Paris, 1848, 26, p. 276-278. 

[On the Sandhill Crane — the non-identity of Grus canadensis and 
Grus mexica7ia]. 
Proc. Boston soc. nat. hist., 1853-1854, 4, p. 303-307. 

[Occurrence of the Yellow-crowned Warbler and Hemlock Warbler 
at Cohasset, Mass. in the month of January]. 
Proc. Boston soc. nat. hist., 1855, 5, p. 142. 

A list of birds observed at Grand Manan and at Yarmouth, N. S. 
from June 16 to July 8, 1856. 

Proc. Boston soc. nat. hist., 1857, 6, p. 114-123. 

[Note on Arctic birds: causes of migration]. 
Proc. Boston soc. nat. hist., 1857, 6, p. 124. 

[On a supposed new species of turkey]. 

Proc. Boston soc. nat. hist., 1857, 6, p. 158, 159. 



BANGS AND PENARD: HENRY BRYANT TYPES OF BIRDS. 199 

[Remarks on some I)irds presented to the Boston Society of Natural 
History by the Royal Victoria Society of Melbom-ne, Australia]. 
Proc. Boston soc. nat. hist., 1857, 6, p. 169, 170. 

[Early appearance of migratory birds]. 
Proc. Boston soc. nat. hist., 1857, 6, p. 170. 

[On some birds observed in East Florida, south of St. Augustine]. 
Proc. Boston soc. nat. hist., 1859, 7, p. 5-21. 

A list of birds seen at the Bahamas, from Jan. 20th to Ma\' 4th, 
1859, with descriptions of new or little known species. 
Proc. Boston soc. nat. hist., 1859, 7, p. 102-134. 

[Note on Tardus mitiiinus Lafresnaye and a new Vireo. J'ireo bogo- 
tcnsis]. 

Proc. Boston soc. nat. hist., 1860, 7, p. 226, 227. 

[Remarks on Trochilus bahamensis Bryant]. 
Proc. Boston soc. nat. hist., 1860, 7, p. 317. 

Remarks on some of the birds that breed in the Gulf of St. Lawrence. 
Proc. Boston soc. nat. hist., 1861, 8, p. 65-75. 

Remarks on the variations of plumage in Buteo borealis, Auct., and 
Butco harlani, Aud.? 

Proc. Boston soc. nat. hist., 1861, 8, p. 107-119. 

Monograph of the genus Catarractes, Moehring. 
Proc. Boston soc. nat. hist., 1861, 8, p. 134-144. 

Description of two birds from the Bahama Islands, hitherto un- 
described. 

Proc. Boston soc. nat. hist., 1864, 9, p. 279, 280. 

Description of a new variety of Parus from Yarmouth, Nova Scotia. 
Proc. Boston soc. nat. hist., 1865, 9, p. 368, 369. 

Remarks on the genus Galeoscoptes Cabanis, with the characters 
of two new genera, and a description of Turdus plumbeus Lin. 
Proc. Boston soc. nat. hist., 1865, 9, p. 369-372. 

Remarks on the type of Butco insignafus Cassin. 
Proc. Boston soc. nat. hist., 1865, 10, p. 90, 91. 

Remarks on Sphyropicus rariwi Linn. 

Proc. Boston soc. nat. hist., 1805, 10, p. 91-93. 

A list of birds from Porto Rico presented to the Smithsonian Insti- 
tution, by Messrs. Swift and George Latimer, with descriptions of new 
species or varieties. 

Proc. Boston soc. nat. hist., 1866, 10, p. 248-257. 



200 bulletin: museum of comparative zoology. 

Additions to a list of birds seen at the Bahamas. 
Proc. Boston soe. nat. hist., 1867, 11, p. 63-70. 

A list of the birds of Santo Domingo, with descriptions of some new 
species or varieties. 

Proc. Boston soc. nat. hist., 1867, 11, p. 89-98. 



New geneea and subgenera proposed by Henry Bryant. 

Kalochelidon Bryant (Proc. Boston soc. nat. hist., 1867, 11, p. 
95) = Lamprochelidon Ridgway. Type. — Hinindo euchrysea domini- 
ccnsis Bryant (not Hirundo dominiccnsis Gmelin) = LamprocJuiidon 
sclaferi (Cory). 

Skotiomimus Bryant (Proc. Boston soc. nat. hist., 1867, 11, p. 68) = 
Mimus Boie. Type. — Mwivs hahamensis Bryant. 

Leucomimus Bryant (Proc. Boston soc. nat. hist., 1867, 11, p. 68) = 
Mimus Boie. Type. — Mimus poh/f/loitus bahamcnsis Bryant. 

MiMOKiTTA Bryant (Proc. Boston soc. nat. hist., 1865, 9, p. 370) = 
Mimocichla Sclater. Type. — Turdiis plumbcus Linne. 

Spizampelis Bryant (Proc. Boston soc. nat. hist., 1866, 10, p. 253) = 
Spindalis Jardine and Selby. Type. — Tanagra prctrci Lesson. 

Shizampelis Bryant (Proc. Boston soc. nat. hist., 1867, 11, p. 68) 
is a typographical error. 

LoxiMiTRis Bryant (Proc. Boston soc. nat. hist., 1867, 11, p. 93). 
Type. — Chrysomitris doviinicensis Br;yant. 



Species and subspecies described by Henry Bryant. 

The following species and subspecies were described as new by 
Henry Bryant. Those marked with an asterisk (*) are represented 
by type or cotype in the M. C. Z. 

Catarractes californicus Bryant (Proc. Boston soc. nat. hist., 1861, 8, 
p. 142. Farrellones Islands, near San Francisco, California) = Uria 
troille californica (Bryant). Type in U. S. N. M. 

* Sula elegans Bryant = Sida dadylatra dacfylatra Lesson. 

Todus hypochondriacus Bryant (Proc. Boston soc. nat. hist., 1866, 
10, p. 250. Porto Rico) = Todiis mcxicamts Lesson. Type formerly 
in U. S. N. M., 36,450, designated by Bryant. 



BANGS AND PENARD: HENRY BRYANT TYPES OF BIRDS. 201 

Psittaciis collarius hahamcnsis Bryant (Proc. Boston soc. nat. hist., 
1867, 11, p. 65. Fortune Island, Auckland Island, and Inagua) = 
Amazona leucocephala bahamensis (Bryant). Type formerly in U. S. 

N. M. 

* Trochilus bahamensis Bryant = Neso phlox evelynae (Bourcier). 

* Saurothcra bahamensis Bryant = Saurothera bahamensis baha- 
mensis Bryant. 

Saurothera vieillotU rufescens Bryant (Proc. Boston soc. nat. hist., 

1866, 10, p. 256. Porto Rico) = Saurothera vicilloti Bonaparte. 
Type formerly in U. S. N. M., 36,440, designated by Bryant; now in 
Mombuspo Museum, Tokio, Japan. 

* Pitangus bahamensis Bryant = Tolmarchus bahamensis (Bryant). 

* Empidonax bahamensis Bryant = Blacicus bahamensis (Bryant). 

Tyrannula carriboea hispaniolensis Bryant (Proc. Boston soc. nat. 
hist., 1867, 11, p. 91. Santo Domingo) = Blacicus hispaniolensis 
(Bryant). Type in U. S. N. M., 42,474, designated by Bryant. 

Tyrannula stolida dominicensis Bryant (Proc. Boston soc. nat. hist., 

1867, 11, p. 90. Santo Domingo) = Myiarchus dominicensis (Bryant). 
Type in U. S. N. M., 41,825, designated by Bryant. 

* Tyranmda stolida lucaysiensis Bryant = Myiarchus sacrae lucay- 
siensis (Bryant). 

Tyrannula bahamensis Bryant (Proc. Boston soc. nat. hist., 1867, 
11, p. 90). Probably a lapsus for Tyrannula lucaysiensis Bryant = 
Myiarchus sacrae lucaysiensis (Bryant). 

* Tyrannu^ antillarum Bryant = Myiarchus antillarum (Bryant). 

* Hirundo cyaneoviridis Bryant = Callichelidoncyaneoviridis (Bryant). 

* Mimus polyglottus bahamensis Bryant — Mimus polyglottos elegans 
Sharpe. 

Mimus cubanensis Bryant (Proc. Boston soc. nat. hist., 1866, 10. 
p. 251; 1867, 11, p. 68, nomen nudum). 

Mimus polyglottus portoricensis Bryant (Proc. Boston soc. nat. hist., 
1866, 10, p. 251. Porto Rico) = Mimus polyglottos orphcus (Linne). 
Type formerly in U. S. N. M., 33,476, designated by Bryant. 

* Mimus bahamensis Bryant = Mimus gundlachii bahamensis 
Bryant. 



202 BULLETIX: MUSEUM OF COMPARATIVE ZOOLOGY. 

Turdus ardosiaceus portoricensis Bryant (Proc. Boston soc. nat. 
hist., 1S()7, 11, p. 93, Porto Rico) = Mimocichla ardosiacca portori- 
censis (Bryant). Location of type unknown. 

* Vireo bogotcnsis Bryant = J^ireo viresccnj Vieiilot. 

* Laniovirco cras&irostris Bryant = Vireo crassirostris crassirostris 
(Bryant). 

* Parus hudsonicus littoralis Bryant = Fenthestcs hudsonicus lit- 
toralis (Bryant). 

* Geothlypis rostratns Bryant = GcothUjpis rostrata Bryant. 

Chrysomitris dominicensis Bryant (Proc. Boston soc. nat. hist., 
1867, 11, p. 93. Port au Prince, Haiti) = Loxirnitris dominicensis 
(Bryant). Type in U. S. N. M., 42,4(34, designated by Bryant. 

* Tanagra dominicensis Bryant = Spindalis dominicensis (Bryant). 

Tanagra portoricensis Bryant (Proc. Boston soc. nat. hist., 1866, 
10, p. 252. Porto Rico) = Spindalis portoricensis (Bryant). Type 
formerly in U. S. N. M., 36,502, designated by Bryant. 

CerthioJa flairoJa portoriwnsis Bryant (Proc. Boston soc. nat. hist., 
1866, 10, p. 252. Porto Rico) = Corrcha portoricensis (Bryant). 
Type in U. S. N. M. 

* Icterus dominicensis portoricensis Bvynnt = Icterus portoricensis 
Bryant. 



Bryant types ix the Museum of Comparative Zoology, 

sula dactylatra dactylatra lesson. 

Sula dactylatra Lesson, Traite d'ornith., 1831, p. 601. (Ascension). 
.Sula elegans Bryant; Proc. Boston soc. nat. hist., 1859, 7, p. 125. (Santo 
Domingo Key, Bahamas). 

Cotype. — M. C. Z., 42,939, cf. Santo Domingo Key, Bahamas, 
April 10. 

Cotype. — M. C. Z., 42,940, 9. Santo Domingo Key, Bahamas, 
April 10. 

Cotype. — M. C. Z., 42,941, 9 • Santo Domingo Key, Bahamas, 
April 10. 

Remarks. — If the l)reeding Bahama bird should prove to be differ- 
ent from that of Ascension, as it well may l)e, then Bryant's name 
becomes available for it. 



BANGS AND PENARD: HENRY BRYANT TYPES OF BIRDS. 203 

Nesophlox evelynae (Bourcier). 

Trochilus evelynae Bourcier, Proc. Zool. soc. London, 1847, p. 44. (Nassau, 
New Providence Island, Bahamas; coll. M. Loddiges). 

Trochilus bahamensis Bryant, Pi'oc. Boston soc. nat. hist., 1859, 7, p. 106. 
(Nassau, New Providence Island, Bahamas). 

Cotype.— M. C. Z., 46,812, d* . Nassau, Bahamas, March 2, 1859. 

CoTYPE.— M. C. Z., 46,813, 9 . Nassau, Bahamas, February 15, 
1859. 

Remarks. — Bryant collected seven specimens, four males and three 
females, all of which are, of course, cotypes. The M. C. Z. now has 
one male and one female. Other cotypes are in the U. S. N. M. 



Saurothera bahamensis bahamensis Bryant. 

Saurothera bahamensis Bryant, Proc. Boston soc. nat. hist., 1864, 9, p. 280, 
(New Providence Island, Bahamas) . 

Cotype.— M. C. Z., 45,972, 9 . Nassau, Bahamas, May, 1859. 
CoTYPE.— M. C. Z., 45,971, o^. Nassau, Bahamas, April, 1859. 



Tolmarchus bahamensis (Bryant). 

Pitangus bahamensis Bryant, Proc. Boston soc. nat. hist., 1864, 9, p. 279 
(Bahamas) . 

Type.— M. C. Z., 46,714. Nassau, Bahamas, April 20, 1857. 

Remarks. — Apparently Bryant took but a single specimen on his 
first trip, this being the only one listed in his catalogue. But there is 
another specimen, M. C. Z., 74,589, with a substituted label, probably 
collected on Bryant's second trip to the Bahamas. 



Blacicus bahamensis (Bryant). 

Empidonax bahamensis Bryant, Proc. Boston soc. nat. hist., 1859, 7, p. 109. 
(Bahamas). 

Cotype.— M. C. Z., 46,715, d" . Nassau, Bahamas. 
CoTYPE.— M. C. Z., 46,716, d . Nassau, Bahamas. 
Remarks. — Bryant mentions having seen three specimens, but 
only two males are listed in the catalogue of his collection. 



204 bulletin: museum of comparative zoology. 



Myiarchus sacrae lucaysiensis (Bryant). 

Tyrannula stolida (var. lucaysiensis) Bryant, Proc. Boston soc. nat. hist., 
1867, 11, p. 66. (Inagua and New Providence Islands, Bahamas). 

?Tyrannula bahamensis Bryant, Proc. Boston soc. nat. hist., 1867, 11, p. 90, 
in text under Tyrannula stolida dominicensis (no locaUty designated). 

CoTYPE. — M. C. Z., 74,553. Bahamas. 

Remarks. — Bryant mentions having collected several specimens 
and gives measurements of an adult male. We do not know where 
the other cotypes now are. 

In the second citation Bryant apparently meant to refer to his 
Tyrannula lucaysiensis and inadvertently used the name bahamensis. 



Myiarchus antillarum (Bryant). 

Tyrannus antillarum Bryant, Proc. Boston soc. nat. hist., 1866, 10, p. 249. 
(Porto Rico) . 

Type.— M. C. Z., 46,885. Porto Rico, winter. Robert Swift. 
Formerly U. S. N. M., 36,459. 

Remarks. — This is the specimen designated by number in the 
original description and is thus the holotype. 



Callichelidon cyaneoviridis (Bryant). 

Hirundo cyaneoviridis Bryant, Proc. Boston soc. nat. hist., 1859, 7, p. 111. 
(Nassau, New Providence Island, Bahamas). 

CoTYPE. — M. C. Z., 46,838, cf . Nassau, Bahamas. 

CoTYPE.— M. C. Z., 46,840, &. Nassau, Bahamas, April 17. 

CoTYPE.— M. C. Z., 46,841, d". Nassau, Bahamas, April 12. 

Remarks. — Bryant mentions seeing this species only on the first 
mile of the road leading to the west end of the island; thirty or forty, 
he says, could be seen at almost all times. He adds that he did not 
kill any specimens after 28 April. 

The catalogue of his collection lists only five specimens of which 
four are now at the M. C. Z. The fifth specimen, a female collected 
1 April, formerly M. C. Z., 46,837, is now in the Thayer museum, 
Lancaster, Mass. This must be the female described. The U. S. N. M. 
also has at least one cotype, and Academy of Natural Sciences of 
Philadelphia has another, 15,639, presented by Dr. Bryant in 1860. 



BANGS AND PENARD: HENRY BRYANT TYPES OF BIRDS. 205 

One of the four specimens listed in Bryant's catalogue, another male, 
M. C. Z., 46,839, bears on its label the date May 1, and must thus 
have been collected when Bryant visited the island in 1866. 

MiMUS POLYGLOTTOS ELEGANS Sharpc. 

Mimus elegans Sharpe, Cat. birds Brit, mus., 1881, 6, p. 339. (Inagua, 

Bahamas). 
Mimus polyglottus (var. bahmnensis " ?") Bryant, Proc. Boston soc. nat. hist., 

1867, 11, p. 68. (Inagua, Bahamas), not Mimus bahamensis Bryant, 

Proc. Boston soc. nat. hist., 1859, 7, p. 114. 

CoTYPE.— M. C. Z., 72,289. Inagua. 

Remarks. — According to Sharpe (Cat. birds Brit, mus., 1881, 6, 
p. 340) there is another specimen collected by Bryant in the collection 
of the British Museum. This specimen must also be considered a 
cotype of Bryant's Mimus polyglottus bahamensis. We do not know 
of the existence of any other specimens of this species of Bryant's 
collecting. 

Mimus gundlachii bahamensis Bryant. 

Mimus bahamensis Bryant, Proc. Boston soc. nat. hist., 1859, 7, p. 114. 
(Berry Islands, Bahamas). 

CoTYPE.— M. C. Z., 46,870, cf . Berry Islands, Bahamas, April 20. 

CoTYPE.— M. C. Z., 46,871, 9 . Berry Islands, Bahamas, April 14, 
1858. 

Remarks. — There is also in the M. C. Z. a specimen from Inagua, 
collected by Bryant, which cannot be considered a cotype. Bryant 
did not visit that island in 1859. 

We doubt whether the form bahamensis can be kept distinct from 
gundlachii, even as a subspecies. 

ViREO viRESCENS Vieillot. 

Vireo virescens Vieillot, Ois. Amer. sept., 1807, 1, p. 84, pi. 53 (no type locality 

stated, we designate Pennsylvania). 
Vireo bogotensis Bryant, Proc. Boston soc. nat. hist., 1860, 7, p. 227. (Bogota). 

Type.— M. C. Z., 47,159. Bogota, N. G. 

Remarks. — Mnscicapa olivacca Linne, Syst. nat., 1766, 1, p. 327, 
based on the Olive-coloured Flycatcher of Edwards, Gleanings nat. 
hist., 1758, p. 93, pi. 253, cannot be used for the Red-eyed Vireo, 



206 bulletin: museum of comparative zoology. 

because Edwards figured and described the Black-whiskered Vireo 
from Jamaica. Vieiilot's Virco virescens appears to be the next name 
in synonymy a\-ailable for this bird. 

The Black-whiskered Vireo, on the other hand, must l)e known as 
Vireo olivaccus (Linne), because Motacilla calidris Linne, Syst. nat., 
1758, 1, p. 184, based on Edwards's American Nightingale, Nat. hist, 
birds, 1750, 3, p. 121, pi. 121, is unrecognizable. The plate certainly 
does not represent a Vireo. The colou ration is wholly different, and the 
bill which Edwards said he drew with great care, has no end hook and 
is shaped like that of a mniotiltid, almost exactly like that of Swain- 
son's Warbler, Helinaia swainsonii Audubon. 

The forms of the Black-whiskered Vireo, therefore, should be known 
as: 

Vireo olivaceus olivacens (Linne). 

Vireo olivaeeiis harbadcnsis Ridgway. 

Vireo olivaceus harhatulus Cabanis. 

Virco olivaceus grandior (Ridgway). 

Vireo olivaceus canescens (Cory). 

Vireo crassirostris crassirostris Bryant. 

Laniovireo crassirostris Bryant, Proc. Boston soc. nat. hist., 1859, 7, p. 112. 
(New Providence Island, Bahamas). 

CoTYPE.— M. C. Z., 46,779, cf . Nassau, Bahamas, April 10; the 
yellow phase {flavescens) . 

CoTYPE.— M. C. Z., 46,780, cT. Nassau, Bahamas, March 20; 
the gray phase. 

Remarks. — Bryant states that three specimens were all he obtained. 
Two, the cotypes mentioned above, are listed in his catalogue. The 
third is in the collection of the U. S. N. M. 

There is another specimen, M. C. Z., 72,562, without original label, 
but bearing the locality Bahamas. It is in much less worn plumage 
than the others and is a very yellow example (phase, flavescens). 
We suspect it came from Inagua. 

Penthestes hudsonicus littoralis (Bryant). 

Parus hudsonicus, var. littoralis Bryant, Proc. Boston soc. nat. hist., 1865, 9, 
p. 368. (Yarmouth, Nova Scotia). 

Cotype.— M. C. Z., 46,976, c^ . Yarmouth, N. S., Jul v 7. 
Cotype.— M. C. Z., 46,977, 9 . Yarmouth, N. S., July 7. 



BAXGS AND PENARD: HENRY BRYANT TYPES OF BIRDS. 207 

CoTYPE.— M. C. Z., 40,978, d". Yarmouth, N. S., July 7. 
CoTYPE.— M. C. Z., 46,979, Y. Yarmouth, N. S., July 7. 
CoTYPE.— M. C. Z., 46,980, Y'. Yarmouth, N. S., July 7. 

Geothlypis rostrata Bryant. 

Geothlypis rostrahis Bryant, Proc. Boston soc. nat. hist., 1867, 11, p. 67. 
(Nassau. New Providence Island, Bahamas). 

Cotype. — M. C. Z., 73,316. Bahamas. 

Remarks. — Bryant mentions three specimens, all males. Ridgway 
(Birds of North and Middle America, 1902, 2, p. 675) claims one of the 
cotypes for the U. S. N. M. We do not know where the third specimen 
is. 

Spindalis dominicensis (Bryant). 

Tanagra dominicensis Bryant, Proc. Boston soc. nat. hist., 1867, 11, p. 92. 
(Santo Domingo and Port au Prince, Haiti). 

Cotype.— M. C. Z., 73,945. Port au Prince, June 10, 1866. A. C. 
Younglo\e. Formerly U. S. N. M., 42,448. 

Remarks. — Ridgway claims no cotypes of this species for the 
U. S. N. M., and we do not know where the other cotypes now are. 
The one listed above was in Dr. Bryant's collection when it came to 
the M. C. Z. 

The description of Tanagra multicolor Vieillot, Enc. meth., 1823, 
2, p. 775 (Florida, Bahamas, and Santo Domingo) is composite, apply- 
ing for the most part to the Black-backed Spindalis zena (Linne). We 
cannot accept the name Spindalis multicolor (Vieillot), on that basis, 
because the only species with a black back in the genus is zena. For 
this very reason Bryant, as stated by himself, discarded Vieillot's 
appellation and named the species dominicensis. 



Icterus portoricensis Bryant. 

Icterus dominicensis var. portoricensis Bryant, Proc. Boston soc. nat. hist., 
1866, 10, p. 2.54. (Porto Rico). 

Type.— M. C. Z., 46,539, adult. Porto Rico, winter, Robert Swift. 

Remarks. — This specimen was in the Bryant collection when it 
came to the M. C. Z. Bryant (/. c.) also mentions and describes the 
plumage of the young bird. 



Jl'l 



Bulletin of the Museum of Comparative Zottlogy 

AT HARVARD COLLEGE. 
Vol. LXVII. No. 4. 



DIAGNOSES OF NEW AMERICAN ARACHNIDA. 



By Ralph V. Chamberlin. 



CAMBRIDGE, MASS., U. S. A.: 

PRINTED FOR THE MUSEUM. 

July, 1925. 



No. 4. — Diagnoses of new American Arachnida. 

By Ralph V. Chamberlin. 

The new arachnids in several collections submitted for identification 
are here diagnosed to render their names available for early use in 
connection with the ecological and other studies which led to the mak- 
ing of the collections. Of these collections mention may be made 
specially of one by Prof. W. C. Alice on Barro Colorado Island, Canal 
Zone, of one by James Zetek made in the course of work on the fauna 
of termite nests, also in the Canal Zone, and of one consisting of speci- 
mens taken from the stomachs of toads and the crops of birds in 
various parts of North America in the course of studies on food-habits 
made by the U. S. Biological Survey at Washington. The types of 
these new species are in the Museum of Comparative Zoology, 
Cambridge. 

ARANEINA. 

Ctenizidae. 

Pachylomerus eremus, sp. nov. 

9 . Carapace and legs dusky brown, paler over a median area in front of 
the strongly procurved thoracic impression. Sternum, coxae of legs beneath, 
and the tarsi yellowish. Abdomen with a slightly purplish cast, the spinnerets 
light brown. Eyes on a slightly elevated tubercle. Area of median eyes 
wider behind than in front in the ratio 13:10. Anterior median eyes with 
diameter not half that of an anterior lateral. Inner margin of furrow of 
chelicera with four teeth, the outer with seven. Labium in type with the 
teeth in three series. Endites with teeth over entire length, those toward 
distal end smaller than the basal ones. Anterior tibiae and tarsi with a band 
of several series of spines along each side. Patellae I and II with an obtuse 
protuberance on caudal side, and patella I with a single spine at distal end on 
anterior side. Patella III with several short spines on anterior side of which 
the distal ones are larger than the others. Tibia III with a few small spines 
across distal end above and several stouter ones at distal end on caudal side. 
Metatarsus III with spines only on distal half above. 

Length, 8.5 mm. 

Type.— M. C. Z. 1,261. 

Locality. — Barro Colorado Island. One female. 



212 bulletin: museum of comparative zoology. 



Pachylomerus oaxacanus, sp. nov. 

9 . Original color altered in preservation. Apparently the cephalothorax 
and legs were light brown and the abdomen dark gray or blackish. Palpi 
flattened, with spines along edges. Anterior legs with the several bands of 
spines along sides as usual. Patella III with a row of spines across distal end 
above and several spiiies back of this row. Tibia III with many spines above 
and on anterior side distad of the depression. Entire upper surface of meta- 
tarsus III covered with spines. Spines along anterior side of metatarsus III 
and ventrally at distal end. Rastellum carried forward on a prominent proc- 
ess above base of claw. Endites with a small triangular patch of stout 
spinules at proximal end, the spinules elsewhere sparse and much weaker. In 
the type there are eight spinules on the labium. 

cf . Tibia of palpus swollen convexly below, the greatest thickness equal to 
half the length, greater than that of femur in about ratio 22:13. Stylus of 
bulb rather short, proximally stout, slightly curved at distal end. 

Length of about 9 mm. 
Type.— M. C. Z. 1,262. 

Locality. — Mexico: Oaxaca. One male and one female from the 
stomach of a toad. 



Dysderidae. 
Ariadna jaliscoensis, sp. nov. 

9 . Carapace chestnut, dusky on sides anteriorly. Sternum and legs also 
chestnut; the tibiae, metatarsi, and tarsi of first pair with tegument darkened; 
femur, patella, tibia, and metatarsus in particular clothed with numerous long 
hairs. The second legs similarly but less densely clothed. Abdomen dark 
gray above, without markings, paler beneath. Median eyes circular, contigu- 
ous, and forming with the posterior laterals a straight line; separated from the 
laterals by their diameter. Tibia I with four pairs of spines beneath, meta- 
tarsus I with nine pairs. Tibia II with four spines under the posterior border 
and two under the anterior border paired with the most distal ones of posterior 
row; two spines on anterior face caudad of the middle. Tibia III with two 
seriate spines beneath. 

Length, 12 mm. 
Type.— M. C. Z. 1,263. 

Locality. — Mexico: S. W. Jalisco, Hacienda San Marcos, 
P. H. Goldsmith. 11-17 July, 1905. One female. 



cil\mberlin: diagnoses of new American arachnida. 213 

Gnaphosidae. 

Gnaphosa peon, sp. nov. 

9 . Carapace and legs dull yellow. Sternum lighter yellow. Abdomen 
dark gray at sides and above or the dorsum somewhat lighter, in part of an 
orange tinge. Venter lighter. Posterior median eyes oblong or subelliptic, 
oblique to each other, separated by half their longest diameter, about once and 
a third that diameter from the laterals. Lateral eyes on each side separated 
by slightly more than their diameter. Anterior row of eyes decidedly pro- 
curved; medians with their diameter five sixths that of the laterals. Clypeus 
equal in height to the diameter of an anterior lateral eye. Tibia I unarmed 
beneath. Tibia II with a single ventral spine, this at distal end. Metatarsi 
I and II each with two pairs of spines beneath. Tibia III with a median dorsal 
spine above. 

Length, 6 mm. 

TiPE.— M. C. Z. 1,264. 

Locality. — Mexico: Vera Cruz. Two females. 

Geodrassus yavapainus, sp. nov. 

9 . Carapace and sternum yellowish brown. Legs yellow. Abdomen 
dark gray above, lighter beneath as usual. The posterior median eyes oblique, 
less than half their longer diameter apart, once and a half that diameter from 
the laterals. Lateral eyes about once and a fourth the diameter of the poste- 
rior one apart. Tibia I with one long spine beneath a little distad of middle. 
The epigynal area is proportionately wider than in phanus and much more so 
than in auriculoides; having much the shape of that of the former species but 
with foveolae more strictly transverse. 

Length, 7.2 mm. Length of cephalothorax, 4.1 mm.; of tibia + 
pateUa IV, 4.1 mm. 

Type.— M. C. Z. 1,266. 

Locality. — Arizona: Yavapai Co. One female from stomach of 
toad. 

Zodariidae. 
Naibena, gen. nov. 

Cephalothorax convex, highest near middle, the pars cephalica but little 
narrower than the pars thoracica, the clypeal region convex. Stria thoracica 
short but distinct. Anterior row of eyes ])rocurved, much shorter than the 
posterior row. Posterior row of eyes straight or nearly so, the medians much 



214 bulletin: museum of comparative zoology. 

nearer to each other than to the laterals; the laterals taken with anterior 
medians forming a strongly recurved row. Area of median eyes longer than 
wide, narrower in front than behind. Lateral eyes widely separated from each 
other. Claw of chelicera small, normal; furrow short, its margins unarmed; 
lateral condyle strongly developed. Sternum pointed behind. Coxae of the 
fourth legs contiguous. Median claw of tarsi borne on an empodium. Tarsal 
claws with numerous, uniseriate teeth. Posterior legs strongly spined, the 
usual verticillate group at end of metatarsus. The usual dense patch of 
seriate setae at distal end of metatarsi. Spinnerets short, anterior and 
posterior pairs subequal, contiguous. 

Genotype. — Naibena barrona, sp. nov. 

Naibena barrona, sp. nov. 

Carapace brown, dusky on the sides. Sternum and legs yellow. Abdomen 
black above, with three pairs of white spots and a single median white spot at 
caudal end. Venter pale, with a median longitudinal dark line and, on each 
side, a dark band arising from caudal end of median line at base of spinnerets 
and running obliquely cephalodorsad to merge in dark of sides. Anterior row 
of eyes decidedly procurved; medians much smaller than the laterals, their 
diameters comparing about as 3:5; medians about their diameter apart, 
farther from the laterals. Eyes of posterior row equal to each other and to 
anterior laterals; medians separated by rather less than a third their 
diameter, nearly twice (1.8) their diameter from the laterals. 

Length, 5 mm. 
Type.— M. C. Z. 1,267. 

Locality. — Barro Colorado Island. W. C. AUee. One not fully 
adult female. 

Theridiidae. 

Vibradellus, gen. nov. 

Pars cephalica strongly slanting forward from the stria thoracica. The 
four median eyes on a forwardly directed process of pedicel as in Vibrada and 
each lateral eye on a small individual pedicel widely removed from the median 
eyes. Abdomen large, subcircular in outline as viewed from above, dorsally 
flattened, not elevated as in Ulesanis, the tegument hard and granular but not 
with distinct scuta such as are present in Vibrada. Sternum cordate. 

Genotype. — Vibradellus carolinus, sp. nov. 

Vibradellus carolinus, sp. nov. 

cf . Carapace dusky brown, without definite markings. Legs yellow except 
the femora which are brown or dusky or yellow only at proximal end. Abdo- 



chamberlin: diagnoses of new American arachnida. 215 

men at present yellow, but it may be more or less bleached. The carapace 
widest posteriorly, narrowing forwards to posterior lateral eyes and then more 
abruptly narrowed to the pedicel carrying median eyes; on each side posteriorly 
a patch of conspicuous pointed tubercles or teeth. Anterior median eyes 
carried far forward above the laterals. Posterior row of eyes strongly re- 
curved, the lateral eyes widely removed from the medians. Legs unspined 
ventrally, but all patellae with several short spines or teeth dorsally and the 
tibiae with at least one at distal end above. Abdomen flattened or somewhat 
concave above, semicircular in outline behind, with a rounded shoulder or 
protuberance a little behind each anterolateral corner. Tibia of palpus with 
a distally truncate, laminate process on ventral side; tarsus proportionately 
large. 

Length, about 3 mm. 

Type.— M. C. Z. 1,268. 

Locality. — South Carolina. One male from stomach of toad. 



Dipoenoides, gen. nov. 

Cephalothorax very high, the height exceeding the width and length, and the 
width exceeding the length. Clypeus several times higher than length of 
chelicerae which are weak. Posterior row of eyes procurved, its eyes nearly 
equidistant. Anterior median eyes widely separated, much closer to the 
laterals than which they are smaller. 

Genoty'PE. — D. apachecus, sp. nov. 

Differs from Dipoena in having anterior median eyes smaller than 
the laterals and the posterior row procur\ed instead of recurved. 



Dipoenoides apachecus, sp. nov. 

cf. Carapace dusky yellow. Sternum nearly black. Legs yellow, spotted 
with black. Abdomen largely bleached out in type but apparently with a 
folium in outline on dorsum, the sides outside of and below the wavy line of 
folium darker than mid-dorsal region, spotted. The setae on dorsum of abdo- 
men stout, spinescent. Tarsus of palpus proportionately very large; bulb 
with two processes arising distad of middle and extending distad beyond the 
end of the cymbium; of these processes the inner (mesal) one, probably the 
embolus proper, is more slender and is nearly straight; the outer process is 
stout proximally but is acutely narrowed distally and is somewhat twisted in 
proximal portion. 

Length, about 3 mm. 

Type.— M. C. Z. 1,269. 

Locality\ — Arizona: Yavapai Co. One male from stomach of toad. 



216 bulletin: museum of comparative zoology. 

LiNYPHIIDAE. 

Bathyphantes castor, sp. noA'. 

cT. Carapace and sternum dusky yellow. The legs also dark yellow 
proximally, lighter distally. Abdomen black, without markings. Posterior 
row of eyes slightly procurved; medians subequal to the laterals, somewhat 
more than their radius from each other and about their diameter from the 
laterals. Anterior median eyes smaller than the laterals, their diameters 
being about as 4 : 5, about their radius from each other and their diameter from 
the laterals. Clypeus depressed just below eyes and then slanting forward to 
base of chelicerae. Upper margin of furrow of chelicera with four teeth of 
which the two most distal ones are raised on a common base. Lower margin 
with two teeth which are minute and close together and opposite the two 
connate ones of upper margin. Embolus of palpus curved around distal end of 
bulb in the typical manner; paracymbium slender, distally geniculate and 
almost uncate. 

Length, 2.5 mm. 

Type.— M. C. Z. 1,270. 

Locality.— Alaska: Beaver Mountains, May, 1920. Two males. 

Argiopidae. 

Glenognatha centralis, sp. nov. 

cf . As the type was taken from the stomach of a toad, details of coloration 
are largely lost. At present the carapace, sternum, and chelicerae are brown, 
the legs yellow, and the abdomen dark, blackish, but it may have had lighter 
markings. On the lower side of furrow of chelicera there are three teeth, a 
small one near base of claw, two much larger ones farther caudad in line oblique 
to the axis of the claw, when closed. On the upper margin of the furrow of the 
chelicera there are also three long, erect teeth of which the middle one is longest 
and the proximal one smallest. The chelicerae are strongly divergent and 
their distal ends are separated by a distance greater than their length. Distal 
process on bulb of palpus in the form of a chitinous blade rolled at the end. 

Length, about 2.2 mm. 

Type.— M. C. Z. 1,272. 

Locality. — Panama. One male from stomach of Bufo sp. 

Eustala conformans, sp. nov. 

9 . Carapace and sternum dull yellow, without markings. Legs dull 
yellow, in part dusky above, clear yellow below. Abdomen broadly sub- 



chamberlin: diagnoses of new American arachnida. 217 

triangular, rounded at corners, flattened above. Dorsum of abdomen grayish 
yellow anteriorly, becoming gray in middle and posterior regions. A median 
cuneate mark at base with narrow end forward; behind middle a dark band 
which abruptly narrows and continues to spinnerets as a band with dentate 
margins and of uniform width. Venter yellowish, dusky in front of spinnerets 
and in a cross-band at middle. Sides dark gray, streaked with black below. 
The epigynmn has much the general form of that of E. semifoliata Cambridge, 
the scape long, strongly cross-wrinkled, narrowed distad to the base of the 
smooth apical process which is shorter and thicker than in semifolutfa. 

Length, 4.2 mm. 

Type.— M. C. Z. 1,273. 

Locality. — Barro Colorado Island. W. C. x\llee. One female. 



EusTALA tuceps, sp. nov. 

9 . Carapace with pars thoracica yellow, the pars cephalica abruptly 
darker, brown or light chestnut, the chelicerae a little darker. Sternum and 
legs yellow, the anterior pairs darker, somewhat dusky yellow. Dorsum of 
abdomen yellowish, with a folium outlined in black, the sides of folium wavy; 
a median longitudinal black line broken anteriorly and the posterior portion 
less distinct. Sides of abdomen dark, the venter gray, without markings. 
The epigynum is characteristic, the posterior plate broad and wholly smooth, 
notched at the middle behind, and the forwardly directed scape very short; 
openings of spermatheca widely separated. Abdomen subelliptic in outline as 
seen from above. 

Length, 7 mm. 

Type.— M. C. Z. 1,274. 

Locality. — Barro Colorado Island. W. C. AUee. One female. 



Pseudometa biologica, sp. nov. 

9 . Carapace yellowish white with the pars cephalica above dusky or 
black, the dark color extending back over the thoracic stria. Sternum black, 
with a median longitudinal yellow stripe acutely pointed behind. Legs yellow; 
the anterior femora dusky distad of the middle and the posterior femora with 
two dusky annuli distad of middle, the joints elsewhere with numerous, mostly 
fine, dark dots on each of which a seta is inserted; tibiae similarly finely dotted 
with dark, a more definite dark annulus at distal end on anterior legs and two 
annuli on posterior tibiae; metatarsi also finely dotted, with a tendency to 
form three or four annuli on anterior legs, the distal two of these annuli being 
most distinct, and three on posterior legs. Abdomen dirty white above; a 
dorsal folium outlined in black, a longitudinal line and veins running out from 



218 bulletin: museum of comparative zoology. 

it faint, but the wavy border distinct, the folium discontinuous caudally how- 
ever; numerous black spots and streaks on each side; venter with an unevenly 
edged, longitudinal black band from spinnerets forward across epigynum. 
Epigynum strongly chitinized, wide in proportion to length ; the usual hammer- 
headed or anchor-shaped median piece shaped much as in P. alboguttafa Cam- 
bridge, but the septal piece not produced at anterior end as in that species, the 
median piece depressed at a marked angle to the anterior part of plate. Abdo- 
men elliptic in outline. 

Length, 10 mm. Length of cephalothorax, 3.5 mm. 
Type.— M. C. Z. 1,275. 

Locality. — California: Pacific Grove, at the Hopkins Laboratory. 
R. V. Ellis. Three females. 



Thomisidae. 
Xysticus lassanus, sp. nov. 

cf . Color-pattern of the ordinary type. Carapace blackish along sides, 
with a wide median longitudinal light stripe as wide anteriorly as eye-area, the 
stripe embracing numerous dark dots and two rather weakly defined dark 
marks placed longitudinally back of posterior median eyes. Sternum light, 
with numerous small brown spots. The species is characterized by the palpus. 
In this the tibial apophysis presents two branches of which the dorsal one is 
pointed while the ventral one is broader, laminate, with its distal end oblique. 
Embolus evenly curved around the periphery of the bulb. A pointed apophy- 
sis below embolus on mesal side and a low median apophysis with principal , 
point directed mesad. 

Length, about 4.8 mm. Length of cephalothorax, 2.2 mm. 
Type.— M. C. Z. 1,277. 

Locality. — Texas: Roberts. One male in poor condition from 
Geococcyx calijorniciis (Lesson). 

Selenopidae. 

Selenops salvadoranus, sp. nov. 

9 . Carapace brown, darker at margins. Sternum and coxae of legs be- 
neath yellow, the sternum somewhat dusky except in the middle area. Legs 
yellowi.sh; femora with two large dark spots beneath; tibiae and metatarsi 
each with two dark annuli which are less pronounced dorsally. Abdomen dark 
gray above, paler beneath. Posterior lateral eyes somewhat less than half the 
diameter of the anterior laterals (13:30). Anterior median eyes three fourths 
their diameter apart. In the epigynum of the female the median piece is 



chamberlin: diagnoses of new American arachnida. 219 

somewhat diamond-shaped with one point extending toward caudal median 
notch and the opposite one continuing forward as a median raised line. 

Length, 13 mm. 

Type.— M. C. Z. 1,278. 

Locality. — San Salvador, January, 1920. One female. 



Sparassidae. 

Olios yucatanus, sp. nov. 

9 . General color of carapace yellow, a faint dark line back of each posterior 
median eye and on each side of pars cephalica some distance back of the lateral 
eye, two dark lines somewhat oblique to each other. Sternum and coxae of 
legs clear light yellow. Legs yellow, without markings. Abdomen above 
yellowish marked with numerous small dark dots which, however, leave a 
clear spear-mark at base behind which the dots on the median line are some- 
what heavier than elsewhere. Venter yellow, a broad dusky area back of genital 
furrow and a dusky spot each side of epigynum. Anterior median eyes a 
little larger than the anterior laterals and also larger than the posterior medians, 
less than their diameter apart, and slightly nearer to the laterals. Posterior 
eyes equal, the medians a little nearer to each other than to the laterals. The 
epigynal depression, viewed from behind, wider than long, not narrowed at the 
open or caudal end, its bordering rim chitinous, the border thickening in front 
crossed by a median longitudinal furrow; the median chitinous piece filling the 
•depression, wider than long, convex behind. 

Length, 10.5 mm. 
Type.— M.C.Z. 1,279. 

Locality. — Yucatan: Chichen Itza, 1 March, 1904. L. J. Cole. 
One female. 

Ctenidae. 

Ctenlts dolomedes, sp. nov. 

(f . Under alcohol the carapace shows a darker median band as wide as the 
eye-area, and the lateral borders are also darkened, the sides otherwise yellow. 
Sternum and coxae of legs yellow. Legs with femora yellow below, crossed 
above with dusky bands or spots which are not sharply limited ; tibiae darkened 
proximally and distally; metatarsi with dusky annulus at each end and one at 
middle. The abdomen with a sagittate mark at base above followed by several 
dark chevrons on posterior portion; dark spots on sides of dorsum. In a 
partly grown specimen there is a broad dark band over the entire length of 
abdomen, the band solid except for two spots enclosed anteriorly. Venter pale 
at sides, with a conspicuous median longitudinal dark band which ends a little 



220 bttlletin: aiuseum of comparative zoology. 

in front of spinnerets and has irregular edges. Area of median eyes wider than 
long (nearly as 6 : 5) , much narrower in front than behind (nearly as 4:5). The 
anterior median eyes much smaller than the posterior medians. Second row of 
eyes decidedly procurved. Posterior medians and posterior laterals equal in 
.size or nearly so. In the palpus the tibial apophysis is moderately broad, with 
distal end slightly convex and not at all acuminate, the apophysis wholly free 
from teeth or spines. The legs are unusually long and tibia plus patella III 
are decidedly longer than the cephalothorax. 

Length, 10.5 mm. Tibia + patella IV, 9.25 mm. 

Type.— M. C. Z. 1,280. 

Locality. — Barro Colorado Island. W. C. Allee. One adult male 
and an immature female. 

Characterized among other Central American species of the genus 
by coloration, the very long legs, and the structure of the palpus,, 
which is distinctive. 

Clubionidae. 

Clubiona bufonis, sp. nov. 

d^. Carapace and sternum light brown. Legs yellow. Abdomen gray. 
Posterior row of eyes straight or nearly so, much longer than the anterior row, 
the eyes widely separated with the medians considerably farther from each 
other than from the laterals. The species is readily differentiated by the form 
of the tibial apophysis. This presents two main branches; of these the upper 
and mesal one is a lamina widened distad and presenting a long distal edge like 
an ax ; the lower branch is divided into two subequal processes which are blade- 
like, but rather narrow and distally truncate. Bulb strongly chitinous; a 
large median chitinous plate has an acute spur from base on outer side, the 
principal part of this plate extending fonvard over bulb as a very broad, 
slightly twisted lamina. The embolus, broad and blade-like at base and be- 
coming distally slender, curves from mesal side around distal end of bulb and 
back proximad on ectal side. 

Length, about 3.5 mm. 
Type.— M. C.Z. 1,282. 

Locality. — Upper Missouri River. One male from stomach of 
toad. 

Chiracanthium falculum, sp. nov. 

cf. Carapace and sternum yellowish brown, the legs similar but more 
yellow beneath. Abdomen gray, unmarked. Anterior row of eyes distinctly 
recurved; median eyes less than their radius apart, a little farther from the 
laterals; the medians a little larger than the laterals. Posterior row of eyes 



chamberlin: diagnoses of new American arachnida. 221 

straight or very slightly procurved, considerably longer than the anterior row, 
the medians farther from the laterals than from each other as usual. Tibiae I 
and II with three pairs of spines below and with three spines on anterior face 
and two on posterior face. The tibial apophysis as viewed from below is 
nearly straight and of uniform thickness until the distal fourth or fifth of length 
is reached when it abruptly narrows into a small, curved, sickle-like blade. 
Embolus encircling the bulb. 

Length, 9 mm. Tibia + patella I, 6 mm.; tibia + patella IV, 
5.2 mm. 

Type.— M. C. Z. 1,283. 

Locality. — Florida: Sebastian, 14 February, 1919. A. Weese. 
One male. 

Anyphaena inferens, sp. nov. 

9 . Carapace brown on the upper part of sides, paler below and in a mid- 
dorsal band. Sternum yellow. Legs light brown, paler beneath. Abdomen 
marked above with a dark median longitudinal dentate band which tends to 
break into distinct chevrons on caudal portion ; at sides many small dark spots 
and streaks. Venter paler yellow, unmarked. Anterior tibiae with four pairs 
of long ventral spines, three spines on anterior face and two on posterior. 
Anterior metatarsi with two pairs of ventral spines. The epigynum presents 
a median longitudinal tongue extending from anterior end and ending about 
one fourth the length from the caudal margin; in front of caudal rhargin two 
transversely elliptic dark areas narrowly separated from each other at middle ; 
on median tongue at its anterior end a second short process projecting caudad. 

Length, up to 7 mm. 

Type.— M. C. Z. 1,354. 

Locality. — Costa Rica. Seven females. 



Mazax segregata, sp. nov. 

9 . Posterior row of eyes straight or but little procurved; the eyes equal or 
very nearly so; median eyes separated by a little more than their radius and 
somewhat closer to the laterals. Anterior median eyes smaller than the 
laterals (ratio of diameters as 7:9); medians less than their radius apart, 
closer to the laterals ; the row strongly procurved, a line through the centers of 
the medians being nearly tangent to caudal edges of laterals. Clypeus a little 
lower than diameter of an anterior lateral eye. Tibia I with six pairs of spines 
beneath; tibia II with five pairs of spines beneath. Metatarsi I and II with 
two pairs of spines ventrally. Lower margin of furrow of chelicerae with two 
teeth. Basal dorsal scutum of abdomen smooth and shining, wholly without 
teeth or processes. Carapace and sternum nearly black. Chelicerae blackish 



222 bulletin: museum of comparative zoology. 

down front face. Femora of legs mostly black, yellowish on ventral side and 
distally, especially on anterior pairs; other joints of anterior pairs yellow or 
tibiae but little darkened. Third legs with tibiae and metatarsi darkened along 
the sides. In fourth legs the tibiae and metatarsi are almost wholly black, 
the tibiae lighter at ends. 

Length, 6.5 mm. 

Type.— M. C. Z. 1,285. 

Locality. — Barro Colorado Island. W. C. Allee. One female. 

Distinguished from other known species in having the anterior 
median eyes smaller than the laterals, and with six pairs of spines under 
tibia