CRLSSI : “ + t by , ese iL Wo, wus ! pal A 4 rote yt 1) eee ha Re ay ie » Dei cin Bb fo” Pre: vl L bAsiiys, CUT say: afd ARTE “ tH Lr hee A im di ‘ tht ah) Beri SMITHSONIAN INSTITUTION UNITED STATES NATIONAL MUSEUM Bulletin 65 - DENDROID GRAPTOLITES OF THE NIAGARAN DOLOMITES AT HAMILTON, ONTARIO Compiled by RAY S. BASSLER Curator, Division of Invertebrate Paleontology U.S. National Museum WASHINGTON GOVERNMENT PRINTING OFFICE 1909 ee we roe SMITHSONIAN INSTITUTION UNITED STATES NATIONAL MUSEUM Bulletin 65 PENPROLD GRAPTOLIIES OF THE NIAGARAN DOLOMITES AT HAMILTON, ONTARIO Compiled by RAY S$. BASSLER Curator, Division of Invertebrate Paleontology U.S. National Museum “Sescacee® WASHINGTON GOVERNMENT PRINTING OFFICE 1909 ‘a Il BULLETIN OF THE UNITED STATES NATIONAL MUSE XN IssuED JuLy 10, 1909. — ADVERTISEMENT. The scientific publications of the National Museum consist of two series—the Bulletin and the Proceedings. The Bulletin, publication of which was begun in 1875, is a series of more or ee! extensive works intended to illustrate the collections of the U. S. National Museum and, with the exception noted below, is issued separately. These bulletins are monographic in scope and are devoted principally to the discussion of large zoological and botanical groups, faunas and floras, bibliographies of eminent natural- ists, reports of expeditions, etc. They are usually of octavo size, although a quarto form, known as the Special Bulletin, has been adopted in a few instances in which a larger page was deemed indis- pensable. This work forms No. 65 of the Bulletin series. Since 1902 the volumes of the series known as “ Contributions from the National Herbarium,” and containing papers relating to the botan- ical collections of the Museum, have bean published as feallecas The Proceedings, the first volume of which was issued in 1878, are intended as a medium of publication of brief original papers based on the collections of the National Museum, and setting forth newly acquired facts in biology, anthropology, and geology derived there- from, or containing descriptions of new forms and revisions of limited groups. A volume is issued annually, or oftener, for distribution to libraries and scientific establishments, and in view of the impor- tance of the more prompt dissemination of new facts a limited edition of each paper is printed in pamphlet form in advance. Ricuarp RaTHBuN, Assistant Secretary, Smithsonian Institution, In Charge of the United States National Museum. Wasuineton, U.S. A., June 20, 1909. Tit TABLE OF CONTENTS. Page TT OCU TO Tie ee ee a ee ee Se 1 IWESERIP LION Obs PENE rasa mUleSpeCles ae 6 ee ae. Ty eee ie es et Se 5 OTdera EN Cir Ol Cae saeee nt eect ere le Ree st IA Pe 5 THUD e NCO ne Glee a eae = ees tT aes ae ee ea 5 GENUSee DEM arOLT AIMS ea ee ene a ee Ee ee 5 CLEA SO TU ee oe Ea A ee Eh 6 OUST US ee ge ee pe a HEPC TVOL OS US eae eae hee a ys ere nN atte nee al 8 NG EUTNT CO SS USS assert tesa ae No hg Sos ene, Re ee Camere Re 8 OT Ve Gara ent Speers ere an a ee 9 SV UTOS US eee eeeen nts ea SS Se a et 10 (DLO DlemaliiCistees = ook AN Ne oe ee eS 10 Bo La eau ts ees ee ea ee eee aft OTEAROCN S16. sess ee se ES ee ees SE AD Genusm Callosran tus fe. 2 Se ae ee eee nh soe Sab 12 VAULT CO SUUU TS pees a es ee fees SR ee ee 3 MIAH REN GIS; aa ed ee eka FAS nee ae, Wicd oh 13 MYL GUS == es Se eee eed ed a ees Se oe Ca eee 14 TVET AUS See) LU Sh ae eee es ee a te ee 15 SS GEST CU Se es ee es ee ee LR Genisee Gill 0 gral tic serene ee iS eee tS ee 16 LOMMACE IS Saree emt, rere eine es ta ie ee 16 GenusP Di Cey Omega sac espeiae stem ee Aes ee Se ee ATG PG Uslil:TS1N) @ eee See ee eee ey ee ED 18 CraSsilbasall Ont Sree eta SS Cee ee eee 19 MOLY MOT pluie eae we en Be ek Se Ee 24 SUDTEGILOP Ie ese eres SSN Ree Nene ee a ee 26 GOW Ma ere ed eS ee en Fo ee 28 SECA GIT © BUTT ar a ae oe a ee Ss 50 No) AS UIIN kee ene gt Rees a Seen ns SS SFO Ee Sl MA MINERVA See cn ame ee ee a ee ee ad ta 54 CLESIMOVG CG h se eae ee Rae ee a ie NEE a ead a 34 BC RCT ASS U Se ese ie eet Be ee we Set OP 3D SDCN COM ieee a> ks eet eal aee ale ST yabe tts Pe et 36 PONE ULES teeter yn eae tee ena eae a Eley 37 Genuse@allyptoorapeuse ones lar ieo ei ee ee 38 CVAIUMIEO ENNIS a eaaes Se ook meee eee ae OE Te St 38 IMMCRONEM At OCS aan a eet ee ee 39 C(I) TREN IER RS ge i 40 SUDZENTISmMrohi ZO Sta il se te es ee BE 40 ULL StS eee rere eee oe ee i 41 VI CONTENTS. Description of genera and species—Continued. Order Dendroidea—Continued. Family Dendrograptidse—Continued. Page. Genus. Odontocaulis=: =. SSeS ee ee es 42 eranti._ 2 ee Oe ee oe 42 obpyriformis: 34. Ses eee eee ee Oe 43 occidentalis 2" ate See Ee ee ee 44 Genus) Cyclocraptus. 22222 See ee 44 rotadentatus: eee eee ee eee 45 Genus Jno0caiulis 2.) ) ee ee ee ee 46 plumulosus 2222302222 eee 46 TramuUlosus 2223-22 ot PS ee eS 49 CérvVICOERDIS 2 ke 2. ee 51 phycoides 2-2-2241 ss eee 51 diffusis: 3.02. 5 4 ee ee 52 diffusts. crassiramus. == 2) oS eee 53 congrecatis 22) Ue ee) ee 54 (62) "STI CTUS Sees ee ns ee eee 54 Veretaliis 2b. eae ge te ee a Se ere 5D thallosus\ == 22a" 2 eae a ar ee eee 55 Genus, Acanthosraptus®== 9-222 22 55 pranti = 6) ee oe ae eee 56 Walkeriios 220): Noe ee ees 57 pulcher 2.20 ce ee ee eee 59 chaeétophorus ee ee ee ee eee 61 MuUltiSpinUS 228 ee eee 61 Gents “Dhami oe reap tS ee 62 bartOWeniSis 2 2) aes ee ee Re ieee oe ee ee 62 BD: TnL OTT See ee 64 Descriptions of plates2222 2-4 ee 65 . \~-= LIST OF ILLUSTRATIONS. PLATES. Facing page. Plate 1.—Figs. 1. 2, Dendrograptus? problematicus Spencer; 38, Dendro- graptus ramosus Spencer; 4, Dendrograptus ontarioensis, IMNEGWalE SD CCLOS eee a ee ee ro a eats ta tes ee SIs ES 66 2.—Fig. 1, Acanthograptus granti Spencer; 2, Dendrograptus phainotheca, new species; 8, Dendrograptus praegracilis Spencer; 4, Dictyonema tenellum Spencer; 5, Inocaulis? thallosus, new species; 6, Inocaulis? strictus, new species____ 68 3.—Fig. 1, Dictyonema crassibasale, new species; 2, Dictyonema stenactinotum, new species; 38, Callograptus strictus, new species; 4, Acanthograptus granti Spencer; 5, Acantho- Sraptis CHhAetopnOLus sueWw SPCClOSs= ame. Sern Se oe TO 4.—Fig. 1, Dictyonema spenceri, new species; 2, Dictyonema pa- rallelum, new species; 3, Dictyonema desmoides, new species; 4, Dictyonema polymorphum Gurley ; 5, Acanthograptus DUCK ers Spen COre a Bieta n Sen eee ree ee eel es (2 5.—Fig. 1, Inocaulis vegetabilis, new species; 2, Inocaulis diffusus CLASSITAMLUS Me Wa Vall Cl yee ee ae ae os eS 74 TEXT FIGURES. Page. Figs. 1-7.—1, Dendrograptus dawsoni Spencer—a frond, natural size, and a branch enlarged; 2, D. dubius Miller ; 3, D. ramosus Spencer—a frond with a branch enlarged; 4, D. praegracilis Speneer; 5, D. spinosus Spencer; 6, D.? problematicus Spencer; 7, D. frondosus Spencer—a frond, natural size, and branch enlarged. (Copied from Spencer) _________________ 8,9.—8, Dendrograptus dubius Miller—an incomplete frond; 9, Dendrograptus ramosus Spencer—a frond branching uwuni- iG TOU meee ae ee aa pee Hees eg ee een eR YS 7 10, 11.—10, Dendrograptus praegracilis Spencer; 11, Dendrograptus phainotheca, new species. View of the type-specimen______ ) 12.—Dendrograptus ontarioensis, new species. View of the most CUMPIETERS WECM Mg = ee et ee ey 13-15.—18, Callograptus minutus Spencer; 14, C. multicaulis Spencer; 15, C. niagarensis Spencer. (After Spencer) _——____ 14 16, 17.—16, Callograptus minutus altus, new variety—view of the Holotype sini siricius new: Species=--2 = 15 18.—Ptilograptus foliaceus Spencer. The type-specimen and a branch senloncedrenGAtien Spencen)=_ = == eer es” 16 VIIl Figs. ILLUSTRATIONS. 19, 20.—Dictyonema retiforme Hall. A small rhabdosome showing the central portion and a portion of a larger specimen______ 21, 22.—Dictyonema crassibasale, new species. Two rather small rhabdosomes showing the proximal portion _______________ 23.—Dictyonema crassibasale. new species. A compressed infundi- buliformerhabdos0im e=322 52s ee ee eee ee 24.—Dictyonema crassibasale, new species. A compressed, fragmen- tary ‘rhabdosome:23s2)s Sones Se es ae ee Ae 25.—Dictyonema crassibasale, new species. Rhabdosome preserving the fibrous proximal portion and showing the thecz________ 26, 27.—Dictyonema polymorphum Gurley. 26, Rhabdosome retain- ing disk (plesiotype) ; 27, A compressed specimen (holotype) with centralcportion{. 2 <2 25 3 ee ee ee ee 28.—Dictyonema polymorphum Gurley. One of Spencer’s types of Calyptograptus subretiformis. (After Spencer) _~_~_-______ 29.—Dictyonema polymorphum Gurley. Spencer’s figured type of Dictyonema tenellum. (After Spencer) _——__________________ 30, 31.—Dictyonema subretiforme (Spencer). 30, One of Spencer’s types of Calyptograptus subretiformis. (After Spencer) ; 31, A large expanded rhabdosome from the Rochester shales of NewYork. (Copiedstrom Ruedemann) =.= 2 ee 32, 383.—Dictyonema tenellum Spencer. 52, A small example presery- ing the basal portion (by R. S. Bassler) ; 33, A larger rhab- WOSOMEC . = Se 2 ee ee ee ; 34, 35. Dictyonema stenactinotum, new species. 384, Holotype; 35, A rhabdosome referred somewhat doubtfully_____-_________ 36.—Dictyonema expansum Spencer. The original type. (Copied LOM. SPN CEL iso ee ee ee es oe ee ne eae ene o¢.—Dictyonema expansum Spencers. = ee ee 38, 39.—Dictyonema filiramus, new species. Two small rhabdosomes_ 40.—Dictyonema filiramus, new species. A rhabdosome of medium 41-48. Dictyonema desmoides, new species. 41, The holotype, a small but rather complete rhabdosome (by R. 8S. Bassler) ; 2, 43, Paratypes. Two fragmentary rhabdosomes___-——__~~ 44,—Dictyonema percrassus, new species. A fragmentary rhabdo- SSO TTC eee eA re re i 8 eee ag eR 45.—Dictyonema percrassus, hew species. Rhabdosome with basal attachment. eo 224 are a ee ee ee 46.—Dictyonema spenceri, new species. Holotype-—__.--_-________ 47.—Dictyonema parallelum, new species. Holotype___--_---__--_- 48.—Calyptograptus cyathiformis Spencer. Copy of Spencer’s figure 49.—Calyptograptus micronematodes Spencer. Copy of Spencer's PT AUT a Nan se Nie ee ee 50.—Calyptograptus micronematodes Spencer. Plesiotype in Spen- eer: collections ee es ees Se ee ae 51.—Calyptograptus? radiatus Spencer. Copy of Spencer's figure___ 52.—Rhizograptus bulbosus Spencer. The type-specimen. (After Spencer). S=5 2 5 ee ee ee 53.—Odontocaulis granti (Spencer). A rhabdosome and a branch of Same enlarged: (AfttersSpencer) -_2 =.= ee 54.—Odontocaulis granti (Spencer). An incomplete rhabdosome___ Page. 19 20 21 22 23 . 24 25 26 27 29 30. 32 3 34 34 39 40 40 41 45 43 ILLUSTRATIONS. IX Fig. 55.—Odontocaulis obpyriformis, new species. View of the holotype a showing rhabdosome and stem enlancedese=-= 22 43, 56.—Odontocaulis occidentalis, new species. A rather complete rhabdosome ___--------=--------------=------------=------ 44 57.—Cyclograptus rotadentatus Spencer. Copy of Spencer’s figure— 45 58.—Cyclograptus rotadentatus Spencer. A large specimen from the Clinton group, Clinton, New York. (After Ruedemann )— 45 59.—Inocaulis plumulosus Hall. os TK ER NN LSS ZL Hf a AA Kt \\ ye Fic. 29.—DicTYONEMA POLYMORPHUM GURLEY. SPENCER’S FIGURED TYPE OF DICTYONEMA TENELLUM. (AFTER SPENCER.) Holotype (selected by Ruedemann).—Cat. No. 54278, U.S.N.M. Plesiotype.—Walker Museum, University of Chicago, No. 13517. DICTYONEMA SUBRETIFORME (Spencer). Calyptograpsus subretiformis SPENCER, Canadian Nat., VIII, 1878, pp. 453, 460. Calyptograptus subretiformis Spencer, Trans. Acad. Sci. St. Louis, IV, 1884, p. 578, pl. 4, fig. 1 (mot fig. 2) ; Bull. Mus. Univ. State Missouri, I, 1884, p. 28, pl. 4, fig. 1 (not fig. 2). Dictyonema ee RUEDEMANN, New York State Mus., Mem. 11, 1908, p: 162; pl. 2, figs. 15 °2. This species is closely related and similar to the preceding form, /). polymorphum, both of which have been described and illustrated by DENDROID GRAPTOLITES OF ITAMILTON, ONTARIO. oN Ruedemann. Spencer’s original description, with additions from his description of 1884 contained in brackets, is given below: Frond circular, but cyathiform in its growing state. There are numerous bifurcating branches, which in the fossil condition imperfectly unite or overlie each ‘other, producing a kind of fine network with irregular sub-rhomboidal [ellipsoidal] interstices. In texture it is corneous, having the branches marked with striations of a sub-rhomboidal form. In this species the branches are much finer (but little more than one-eightieth of an inch in width [0.85—0.75 mm.]) than in C. cyathiformis, with more numerous and irregular bifurcations, producing a netted appearance. The original matter is often replaced by pyrites. The fronds are not generally more than two inches ies, 380, 31.—DIcTYONEMA SUBRETIFORME (SPENCER). 30, ONE OF SPENCER'S TYPES OF CALYPTOGRAPTUS SUBRETIFORMIS. (AFTER SPENCER.) 381, A LARGE EXPANDED RHABDO- SOME FROM THE ROCHESTER SHALES OF NEW YORK. (COPIED FROM RUEDEMANN.) in diameter. Only a few specimens have been found, and these show some varietal differences, This species was found in the Niagara limestone [principally in the shaly dolo- mites beneath the chert bed], Hamilton, Ontario, by Colonel Grant. To this description Gurley adds the following: Measurements of a number of branches show that these nearly all fall between 0.4 mm. and 0.6 mm., 0.4-0.5 being the dimensions usual in the distal portion for the branches exclusive of the terminal twigs. The more proximal stems meas ure 0.6 mm., and the thickest seen (in one specimen only) reached 0.8 mm. Cor responding to the straggling aspect of this species almost any number of branches may be counted transversely, but if portions be selected where the branches are 28 BULLETIN 65, UNITED STATES NATIONAL MUSEUM. at fairly regular distances apart and the meshes consequently of pretty uniform width, the number will be found to be about 25 (say 23-27). Ruedemann® says, in connection with the generic position of the species : As both Spencer’s drawings and our material show, these [generic] characters are not retained in his second species, C. subretiformis. The latter clearly pos- sesses dissepiments, which, however, are so oblique that they appear as bifurea- tions [See Spencer’s figure, here copied.] Dictyonema polymorphum Gurley indi- cates transition from a typical Dictyonema with rectangular meshes to this irregularly meshed form. The clearly closer relationship of the present species to Dictyonema polymorphum than to C. cyathiformis has induced us to place it under the former genus and to restrict Calyptograptus to forms which retain the diagnostic characters of the genotype. DICTYONEMA TENELLUM Spencer. Plate 2, figure 4. Dictyonema tenella SPENCER, Canadian Nat., VIII, 1878, pp. 45S, 459. Dictyonema tenellum Spencer, Canadian Nat., X, 1882, p. 165; Trans. Acad. Sci. St. Louis, IV, pp. 564, 576 (not pl. 1, fig. 18); Bull. Mus. Univ. State Missouri, I, pp. 14, 26 (not pl. 1, fig. 18).—MuILtEer, North Amer. Geol. and Pal., 1889, p. 185.—Gurtey, Journ, Geol., IV, 1896, pp. 96, 308. The original description is as follows: Frond cyathiform in growing state, but usually circular, although occasional specimens have a flabellate form in the rock. The branches are uniform, nearly parallel, and radiate from the center with very few bifurcations; in width they vary from one one hundred and twentieth to one-eightieth of an inch, but uni- form in the same specimen. The branches are connected at short intervals by transverse dissepiments; while the margin of the frond is remarkably constant. The surface is striated, and the texture has a corneous character like that of the other species of this group.? 4New York State Mus., Mem. 11, 1908, p. 164. » Here is interpolated in the description of 1884, a paragraph which I footnote, being convinced that with the exception of the statement that ‘‘ between the branches there are not usually spaces as great as (or greater than) their own width,” it has no reference to the species now under consideration. “In the best specimens distinct ellipsoid pits are arranged along the sides of the branches, marking the positions of the calycles, these having the longer diameter equal to half a millimeter and their shorter occupying two-thirds of the width of the stipe. There are about twenty-four of these calycles arranged longitudinally in the length of a centimeter. In specimens less perfectly pre- served the bars connecting the branches are almost obliterated, and in those in a better state of preservation they are placed from 2 to 38 mm. apart, while between the branches there are not usually spaces as great as (or greater than) their own width.” Respecting the species to which he does refer, I can only say that in my expe- rience, D. crassibasale more usually than any other species, has the thecx pre- served, and that those structures in crassibasale could be deseribed in about the words used. But in no species could be both 0.5 mm, long. and 24 in 1 em,— R. R. Gurley. DENDROID GRAPTOLITES OF HAMILTON, ONTARIO. 29 As the connecting filaments are very fine, owing to imperfect preservation, they are not always distinct over the whole surface of the frond. ‘This species is easily distinguished from D. gracilis—even in fragments—by the branches being exceedingly fine (about one-hundredth of an inch in width), with scarcely that distance between them, and with no approach to the dendritic form of that species. The frond maintains its character even in the young state. The larg- est frond is three and one-half inches in diameter. It occurs in the Niagara limestone [dolomitic limestones of the cherty beds and in the underlying more shaly rocks; 1884] at Hamilton, Ontario. The speci- men described was obtained by Lieutenant-Colonel Grant, and presented to the writer. Spencer’s description of 1884 adds, that the dissepiments are very delicate, and the margin entire. He further says: This species is easily distinguished from D. gracile [=D. crassibasale Gurley] by the branches being much finer, less diverging, and with more bifurcations, by the transverse bars being more closely arranged, and by the frond being 33 See LZEP 2” Figs. 32, 33.—DICTYONEMA TENELLUM SPENCER. 32, A SMALL EXAMPLE PRESERVING THD BASAL PORTION. (By R. S. BASSLER.) 33, A LARGER RHABDOSOME. regularly circular, with no general bush-like form like that seen in most specimens of D. gracile [crassibasale]. The largest frond is 9 em. in diameter. Gurley’s description of the species is as follows: Polypary cyathiform, in the flattened state radiating from a center; proximal extremity only indistinctly visible in one specimen (text fig. 32), appearing to consist of some kind of a bulbous or fibrous root. Branches straight, mostly 0.5-0.55 mm. wide; a few as narrow as 0.25; occasionally one as wide as and none wider than 0.4 mm. Number of branches transversely in 25 mm., proxi- mally about 45, distally 50-55. Interspaces consequently rarely as wide as and usually much narrower than branches. Minimal length of meshes about 0.5 mm., maximum about 1 mm. Thecie invisible. Dissepimenta of about medium thickness, straight or oblique. The identification of this species I consider thoroughly made out. There is no other species at Hamilton, at least in my experience, to which Spencer’s orig- inal description could refer. But in 1884 Spencer figured as D. tenellum a 30 BULLETIN 65, UNITED STATES NATIONAL MUSEUM. totally different species, the one I have named D. polymorphum. It is very important to note that his description, too, has become tinctured with foreign elements, the whole of the second paragraph, with the possible exception of the statement that ‘‘ between the branches there are not usually spaces as great as (or greater than) their own width,” having no application to the present species. Horizon and locality—Not uncommon in the Niagara dolomite, chert, and glaciated chert at Hamilton, Ontario. The originals of text figure 32 and Plate 2, figure 4, are in the National Museum, while the third figured specimen (fig. 33) belongs to the Spencer collection. Plesiotypes.—Cat. No. 55300, U.S.N.M. DICTYONEMA STENACTINOTUM Gurley, new species. Plate 3, figure 2. Gurley’s description of this fine new species follows: Polypary flabelliform, included within an angle of 35°, somewhat obscure at base; branches 0.6—0.8 mm. wide (in places apparently as narrow as 0.4 mm., but they are there not fully exposed, as the same branches elsewhere show in their course the full width) ; mostly parallel, in places curving irregularly, causing distortion of the meshwork; set 17-18 in 25 mm. of width. Dissepi- ments slender or thick, sev- eral reaching 0.6 mm. and but for their position being virtually indistinguishable from a nearly transverse branch. The majority are transverse, though many are more or less and some are quite oblique. Most are Fics. 34, 85.—DICTYONEMA STENACTINOTUM, NEW Parallel-sided; a number are SPECIES. 384, HOLOTYPE. 35, A RHABDOSOME RE- triangular. In general the FERRED SOMEWHAT DOUBTFULLY. (SEE ALSO PL. 3, meshwork is regular, the meshes rectangular. The most regular meshes vary in length between 1.5 and 2.5 mm. Distorted meshes may be as short as 0.5 mm., though more usually 1 mm. is the minimum. Only obscure indications of thecw are seen. The above description refers to the type-specimen alone [fig. 84]. One other specimen [text fig. 35, Pl. 3, fig. 2], from approximately the same horizon, exhibits a general resemblance to the type, but with some differences. It may be described as follows: Polypary known only in the form of a fragment of the meshwork; branches heavy (0.8 mm. wide), parallel, diverging only very slightly, bifurcating cor- respondingly rarely (the few successive bifurcations visible are 12-20 mm. apart) ; set 15 or 16 in 25 mm, of width. Dissepiments when unworn probably FIG. 2.) DENDROID GRAPTOLITES OF HAMILTON, ONTARIO. oA always heavy (0.4, 0.6, 0.8 mm.), though as seen they are sometimes slender, usually transverse, sometimes oblique. Meshes coarse, rectangular, about 35 mm. or more in length, though occasionally one is seen as short as 1.5-2.5 mm. Apparently the length may reach 5 or even 6 mm., but in one mesh of this character two intermediate dissepiments can be made out on close observation. So that the superficial aspect of the fossil is not to be implicitly trusted. Careful comparison with the three species (websteri, retiforme, percrassus) to which this form comes nearest, shows it to be distinct from all; from the last two it may be known by the absence of the rapid radiation of the polypary. Horizon and locality—Two specimens in National Museum, both from the Niagara dolomite, Hamilton, Ontario. Holotype and paratype.—Cat. No. 55299, U.S.N.M. DICTYONEMA EXPANSUM Spencer. Dictyonema cxrpansum SpPENcER, Trans. Acad. Sci. St. Louis, IV, 1884, pp. 564, 575, 576, pl. 2, fig. 1; Bull. Mus. Univ. State Missouri, I, 1884, pp. 14, 25, 26, pl. 2, fig. 1.—GurRLEy, Journ. Geol., IV, 1896, pp. 96, 308. Spencer’s original description is as follows: Frond flabelliform, composed of slender, expanding, and bifurecating branches, diffusely arranged, and united laterally by slender filaments (often wanting) ; branches irregularly striated; texture corneous. This species is clearly related to D. gracile in the relative size of the branches, but these are much more diffusely and irregularly arranged, with greater inter- spaces, which are from two to four times the width of the branches. The transverse filaments occur less frequently than in D. gracile. Fragments of this species are not always easily distinguishable from D. gracile, although the branches are looser and more spreading. The type specimen is 8 cm. high and about 16 broad, rising from a united base of five or six stipes. Formation and locality.—Niagara limestones at Hamilton, Ontario. Doctor Gurley describes a specimen of this species as follows: There is in all the Hamilton collections but one specimen which I could by any possibility refer to Spencer’s erpansum. It may be described as follows: Polypary 120 mm. high and 285 mm. broad; flabelliformly compressed, semi- circular in outline, consisting proximately of eight parallel branches, and higher up of numerous branches, which are approximately straight (or with long, sweeping curves) and subparallel; the extreme lateral ones perpendicular to the median line of the pclypary, nearly straight, the whole curvature occurring proximally in a short turn. Width of branches pretty uniformly 0.8 mm., one being occasionally seen 1 mm. wide. Distally the specimen is so worn that it is hard to say whether the full width is maintained to the periphery or not, but a few unworn branches there measure 0.8 mm. The branches are eyery- where set about 17 in 25 mm. of width. Concerning the number of dissepi- ments, nothing can be said, the specimen being too much worn. No thece are visible. Horizon and locality——One specimen in Spencer’s collection, labeled Dic- tyonema retiforme, from the Niagara dolomite, Hamilton, Ontario. I can not say that I feel entire confidence in the identification, but I think this is Spencer’s species. As above remarked, it is the only one in the collec- tions which could be erpansum, and it agrees as well with Spencer’s descrip- on BULLETIN 65, UNITED STATES NATIONAL MUSEUM. tion, and particularly with his figure, as a poorly preserved specimen could be expected to. VParenthetically, I may say that it seems distinct from all the (COPIED FROM SPENCER.) THE ORIGINAL TYPH. 56.—DICTYONEMA EXPANSUM SPENCER. Fic. other species at Hamilton. Among its distinctive marks may tentatively be named: The perpendicularity of the extreme lateral branches of the median DENDROID GRAPTOLITES OF HAMILTON, ONTARIO. ao line of the polypary, and the restriction of the curvature of the branches within space toward their proximal end, the approximately straight course o a short sp 34 BULLETIN 65, UNITED STATES NATIONAL MUSEUM. DICTYONEMA FILIRAMUS Gurley, new species. Gurley’s description of this species is as follows: Polypary varying from flabelliformly compressed, nearly and regularly semi- circular, about 25-80 mm. in radius, to flabellate expansions 14 or more cm. in diameter. Branches straight or uniformly curved, mostly 0.8 mm. wide, reaching 0.4 mm., especially near the base; set about 40 in 25 mm. (7-9 in 5 mm., the strong radiation } I preventing counting for longer distances.) Bifurca- tions narrow, tending to V-shape. Dissepiments ex- ceedingly fine; rather uni- formly 1 mm. apart, occa- sionally two as close together as 0.5 mm.; quite uniformly transverse. Meshes quite regular, rectangular. Too few thece are visible to per- mit of any accurate estimate of their number, but they seem to be something like 100 or more in 25 mm. Horizon and locality.— Not uncommon in_ the dolomite and chert at Fic, 40.—DICTYONEMA FILIRAMUS, NEW SPECIES, eA Hamilton Ontario RHABDOSOME OF MEDIUM SIZE. c * c . Cotypes.—Cat. No. 55308, U.S.N.M. DICTYONEMA DESMOIDES Gurley, new species. Plate 4, figure 3. Gurley describes this species as follows: Polypary cyathiform, flabelliformly compressed, tending to spread rather widely, with branches 0.6 mm. (0.4—0.6 mm.) wide, the central ones usually straight, or only slightly undulate, the lateral ones diverging moderately, or DENDROID GRAPTOLITES OF HAMILTON, ONTARIO. 35 sometimes extremely and often undulate or more or less tortuous, and really or apparently fusing Desmograptus fashion. In places where the meshwork is laid down evenly and without distortion there are about 30 branches in 25 mm. of width. Proximally the number may perhaps be somewhat less (say 27). Distally, especially laterally, where the branches are reflexed, and, in some places crowded, there may be 35 in 25 mm., a condition perhaps due to distortion. The interspaces then are, in general, narrower than the branches, and much narrower distero-laterally, where the latter are crowded. The dissepiments are heavy (0.2-0.4 mm. thick), and apparently somewhat remote, but the exact Fics. 41—43.—DIcTYONEMA DESMOIDES, NEW SPECIES. 41, THE HOLOTYPE, A SMAEL BUT RATHER COMPLETE RHABDOSOME. (By R. R. BASSLER.) (SEE ALSO PL. 4, FIG. 3); 42, 43, PARATYPES. TWO FRAGMENTARY RHABDOSOMES. distance cannot be stated. Meshes rectangular, elliptic, or irregular. Thecze Or obscure, but apparently about 50 in 25 mm. Horizon and locality.—Niagara chert, Hamilton, Ontario. Holotype-—New York State Museum, Albany, New York. Paratype.—Cat. No. 55304, U.S.N.M. DICTYONEMA PERCRASSUS Gurley, new species. Doctor Gurley’s description is as follows: Portion of the polypary seen (incomplete proximally) flabellate, radiating rather rapidly, the width increasing, in one specimen, in the longitudinal or radial dis- tance of 30 mm. from 8.5 to 38 mm. and the branches from 7 to 21. The width thus in- creases more rapidly than the branches. The increased space is, however, taken up by the increased thickness of the branches, which, in proceeding from the base, rapidly increase to a width of about 0.8 mm. and at the periphery may reach 1 mm. Proximally a few are as narrow as 0.4 mm., but nearly Fic. 44.-DICTYONEMA PERCRASSUS, all are 0.5 mm., and some measure 0.6 mm. NEW SPECIES. A FRAGMENTARY Distally the interspaces are quite or very RHABDOSOME. nearly as wide as the branches, but never wider. Proximally, however, they are about 14 times as wide as the branches or (with the narrowest branches) even a little more. Proximally the number a4 36 BULLETIN 65, UNITED STATES NATIONAL MUSEUM. of branches is about 20 in 25 mm. of width. Distally it ranges from 14 to 17. The dissepiments are not very slender (reaching a width of 0.2 mm. ad max.), straight or oblique, sometimes two diverging from a common point of origin on the branch. Length of meshes probably (when all the dissepi- ments are preserved and visible) not much exceeding 2 mm. The dissepiments are, in many places, obscure, but seem usually to be 1.5—2.0 mm. apart. Smallest complete meshes about 1 mm. long. 3ranches obscurely striate. Thecze invisible. Horizon and locality.—Glaciated chert beds, Niagara formation, Hamilton, Ontario. This species is characterized especially by the very great thickness of its branches, the general radiating aspect of the polypary, and the small number of branches transversely. Fic. 45.—DICTYONEMA PERCRASSUS, NEW SPECIES. RHABDOSOME WITH BASAL ATTACHMENT. Cotypes.—Collection of Walker Museum, University of Chicago, No. 13511; Spencer collection. DICTYONEMA SPENCERI Guley, new species. Plate 4, figure 1. Doctor Gurley’s description follows: Polypary circular or flabelliform, consisting of heavy branches, mostly about 0.8 mm. wide, some as narrow as 0.6 mm., set about 17-20 in the proximal portion and usually about 20-22 in 25 mm. of width in the peripheral portion of the polypary, nearly straight, subparallel, with about 4 6r 5 bifurcations in their course toward the periphery. Dissepiments usually slender, though an occasional one reaches 0.5 mm., usually 1.5-2 mm. apart, and in many cases a 5 mm, interval is seen without any trace of an intermediate dissepiment sub- dividing this long mesh. But in other cases similar long meshes are seen, on close inspection, to be subdivided by an intermediate dissepiment. Meshes sub- quadrangular. Horizon and locality—Five specimens from the Niagara chert, Hamilton, Ontario. DENDROID GRAPTOLITES OF HAMILTON, ONTARIO. 37 This species has the branches slightly thicker and somewhat more numer- ous than in D. retiforme, which it most resembles. It is therefore a closer form than retiforme, the interspaces usually tending to be narrower, or at least not wider than the branches, especially distally, where, on the contrary, in D. retiforme, the tendency is for the interspaces to be, relatively to the branches, f Fic. 46.—DiIcTYONEMA SPENCERI, NEW SPECIES. HOLOTYPE. (SEE ALSO PL. 4, Fic. 1.) widest, this condition resulting from a tendency of its branches to spread too rapidly for bifurcation to keep pace with the spreading. This of course shows in the number of branches in 25 mm. of width, which at the periphery of D. retiforme tends to sink to say 15. Holotype.—Cat. No. 55301, U.S.M.A. DICTYONEMA PARALLELUM Gurley, new species. Plate 4, figure 2. The description by Gurley is as follows: Polypary originating from a fibrous root; consisting of vigid, wiry, parallel, little-diverging branches, mostly 0.4 mm. wide, but reaching 0.6 mm, in the proximal portion; set 35-40 transversely in 25 mm. Meshes correspondingly narrow, being usually about one-half as wide (but, from slight curving of the branches, may for short distances be Fic. 47.—Dicryo- as wide) as the branches. Bifurcations not numerous. NEMA PARALLELUM, 3ranches connected laterally both by slender, transverse NEW SPECIES. HOLOTYPE. (SEE Atso Pu. 4, ric. 2.) — dermis; the latter about as wide as the branches. Judg- ing from the few seen, the dissepiments are about 2.5 mm. apart, but this may easily be erroneous, as intermediate ones may have been dissepiments, and in places by transverse bands of epi- destroyed. The epidermis over the branches is in several places crossed by transverse lines which probably mark the position of thecee. These lines are approximately half a millimeter apart (corresponding to about 50 thece 1M 2a TM.) This species is easily recognizable by the rigid, wiry branches, very thickly set, with correspondingly narrow (nearly obliterated) meshes. 38 BULLETIN 65, UNITED STATES NATIONAL MUSEUM. Horizon and locality —Niagara dolomite, Hamilton, Ontario. Collector, Col. C. C. Grant. 5 Holotype.—Collection of Walker Museum, University of Chicago, No. 13505. Genus CALYPTOGRAPTUS Spencer. Calyptograpsus SpeNcerR, Canadian Nat., VIII, 1878, p. 458. Calyptograptus, LAPworTH, Quart. Journ. Geol. Soc. London, XXXVIT, 1881, p. 173.—SpPencrErR, Proc. Amer. Ass. Adv. Sci., XX XI, 1883, p. 364; Trans. Acad. Sci. St. Louis, IV, 1884, pp. 562, 577; Bull. Mus. Univ. State Missouri, I, No. 1, 1884, p. 27.—MIL.LER, North Amer. Geol. and Pal., 1889, p. 175.—GurLEy, Journ. Geol., IV, 1896, pp. 938, 308.—RUEDE- MANN, New York State Mus., Mem. 11, 1908, p. 163. Doctor Ruedemann® publishes the following on this genus: Spencer has erected the genus Calyptograptus for several species of the Ni- agaran of Hamilton, Ontario, which are principally distinguished from the similar genera, notably Dictyonema and Callograptus by the absence of trans- verse dissepiments. In the first diagnosis it is stated that “in appearance and texture this genus resembles Dictyonema, but the branches are [apparently] all independent, not being connected by transverse dissepiments as in that genus and are only united in one mass at the root” [although some of the branches touching each other have occasionally all the appearance of connecting fila- ments]. This statement has later (1884) been qualified by the same author by the additions here placed in brackets, both of which tend to admit the occasional presence of dissepiments. The absence of the dissepiments and the independ- ence of the branches down to the root, which may be considered as additional diagnostic characters of the genus, find their strictest expression in C. cyathi- formis the form which is cited as,the genotype by Miller [N. Am. Geol. and Pal.'1889, p. 175.] CALYPTOGRAPTUS CYATHIFORMIS Spencer. Calyptograptus cyathiformis Spencer, Canadian Nat., VIII, 1878, pp. 458, 460: Trans. Acad. Sci. St. Louis, IV, 1884, pp. 564, 578, pl. 3, fig. 3; Bull. Mus. Univ. State Missouri, I, 1884, p. 28, pl. 3, fig. 83—MILLER, North Amer. Geol. and Pal., 1889, p. 175, fig. 145.—GuRLEy, Journ. Geol., 1896, pp. 93, 308. The following is Doctor Spencer’s original description, the brack- eted portions being taken from his description published in 1884: Frond eyathiform, with numerous bifurcating branches, united only at the base, with no lateral processes; the axis consists of a black corneous substance, which is striated longitudinally. The fallen frond has some of the branches overlying each other, forming a coarse [giving somewhat the appearance of an irregular] network. The radicle consists of a well-marked, thick, corneous mass. The branches are about three-hundredths of an inch in breadth [rather over a millimeter]. The specimen under consideration is most interesting. When @New York State Mus., Memoir 11, 1908, p. 163. DENDROID GRAPTOLITES OF HAMILTON, ONTARIO. 39 obtained the frond had a general flabellate form with the radicle well marked, having branches radiating to nearly a semicircle; but on trimming the speci- men the portion of the stem with radicle was chipped off and revealed the remainder of a beautiful frond which was now shown to be circular—[the frond having been bent partly over in the mud, and having the lower portion covered before the whole was flattened in the sediment] thus proving the funnel-shaped character when living. This fossil is 25 inches in diameter, and from the base of the root to the top of the branches it measures 1 inch and a half. It occurs in the Niagara limestone [beneath the chert at the * Jolly Cut ”’] at Hamil- ton, Ontario. The description of 188+ also adds that the branches are divided into two or three small terminations which probably mark the besimining of new branches, and that only one specimen, 6 em. in Fic. 48.—CAtyproGRaPTUS CYATHIFORMIS SPENCER. diameter, and 4 em. from pe Rape gee ce the base of the root to the top of the branches, was found. No additional specimens were noted in the more recent collections, so the species is undoubtedly very rare. CALYPTOGRAPTUS MICRONEMATODES Spencer. Calyptograptus micronematodes SPENCER, Canadian Nat., X, 1882, p. 165, nomen nudum; Trans. Acad. Sci. St. Louis, LV, 1884, pp. 564, 579, 588, pl. 3, figs. 4, 4a; Bull. Mus. Univ. State Missouri, I, 1884. pp. 14, 29, 38, pl. 3, figs. 4, 4a. Calyptograpsus micronematodes GuURLEY, Journ. Geol., IV, 1896, pp. 93, 308. The original description is as follows: Frond cyathiform in its growing state, with numerous lateral branches originating from the older stipes. The branches overlie each other, Fig, 49.—CALYProGRaPTUS MI- and may be united in some cases, but without CRONEMATODES SPENCER. Copy = true crossbars. The whole frond has an anas- OF SPENCER’S FIGURE. tomose appearance with irregular rhomboidal] interstices. The texture is corneous (though sometimes replaced by pyrites, and the surface is marked with longitudinal striations, which in some places $2651—Bull. 65—09——4. 40 BULLETIN 65, UNITED STATES NATIONAL MUSEUM. appear to represent the position of a solid central axis. The terminations of the branches end in two or three points. The branches in this species are very delicate being about a quarter of a millimeter broad, and each branch is not Fig. 50.—CALYPTOGRAPTUS MICRONEMATODES SPEN- CER. PLESIOTYPE SPENCER COLLECTION IN more than from 1 to 2 millimeters in length, before it overlaps or touches the adjacent stipe. The greatest diameter of the frond is not more than 4 em. Only two or three specimens of this beautiful little frond have been obtained. Formation and locality.—I obtained this species, near the base of the Niagara dolomite, at a quarry just west of the ‘* Jolly-cut-road,” Hamilton, Ontario. A single specimen of this species, repre- sented in figure 50, is at present extant in the Spencer collection. It does not permit of any substantial addition to the above descrip- tion. The branches show some _ longitudi- nal chitinous striz, but there are no indica- tions of thece or dissepiments. CALYPTOGRAPTUS ? RADIATUS Spencer. Calyptograptus ? radiatus Spencer, Canadian Nat., X, 1882, p. 165, nomen nudum; Trans, Acad. Sci. St. Louis, IV, 1884, pp. 564, 580, pl. 4, fig. 3; Bull. Mus. Univ. State Missouri, I, 1884, pp. 14, 30, pl. 4, fig. 3. Calyptograpsus radiatus GuRLEY, Journ. Geol., IV, 1896, pp. 93, 308. The original description is as follows: Frond ellipsoid, but cyathiform in its growing state. Numerous delicate branches, with two or three bifurcations, radiating from a common radicle. Some of these touch or overlie each other, but they are quite unconnected. The texture is corneous, with the surface striated and marked with minute depres- sions or pits, which indicate the former position of the cel- lule. These depressions are about the fourth of a millimeter in diameter, with an equal space between. The branches are about one-third of a millimeter broad. The greatest diame- ter of the frond is less than 3 cm. Fragments of this species so resemble species of Callograptus that they could not be readily distinguished ; but in no species of the latter genus is the conspicuous funnel form apparent. Trormation and locality.—This fossil occurs in the “cherty beds” of the Niagara dolomite at: Hamilton, Ontario. Subgenus RHIZOGRAPTUS Spencer. I'1g.51.—CALyptTo- GRAPTUS ? RADI- ATUS SPENCER. Copy OF SPEN- CER’S FIGURE. Rhizograpsus SPENCER, Canadian Nat., VIII, 1878, p. 460.—Gur.Lry, Journ. Geol., IV, 1896, pp. 101, 308. Rhizograptus LAPworTH, Quart. Journ. Geol. Soe. London, XXXVIT, 1881, p. 176.—Spencer, Proc. Amer. Ass. Adv. Sci., XXXI, 1883, p. 364; Trans. Acad. Sci. St. Louis, IV, 1884, pp. 562, 580; Bull. Mus. Univ. State Missouri, I, 1884, p. 30.—MILLER, North Amer. Geol. and Pal., 1889, p. 202. i. ee ee ee ee ee eee et DENDROID GRAPTOLITES OF HAMILTON, ONTARIO. 41 Below is given Doctor Spencer’s original description, with addi- tional characters, as published by him in 1884, placed in brackets. Frond flabellate, but cyathiform in growing state; bifurcating branches with dichotomous terminations; [stem terminating in a well-marked bulb]; branches (marked with strie) more or less reticulated, and united, or overlaid by others. This genus is established on account of its bulbous root, which as yet has been found in no other species of this family. The numerous branches closely overlie each other or are connected in the form of a network without transverse dis- sepiments, as in Dictyonema. Fragments of these somewhat resemble species of Calyptograptus, but have a much more [regularly] netted appearance and the branches are much more delicate. Genotype—Rhizograptus bulbosus Spencer. RHIZOGRAPTUS BULBOSUS Spencer. Rhizograpsus bulbosus SPENCER, Canadian Nat., VIII, 1878, p. 460.—Gur.Lry, Journ. Geol., IV, 1896, pp. 101, 308. Rhizograptus bulbosus Spencer, Trans. Acad. Sci. St. Louis, IV, 1884, p. 580, pl. 4, fig. 4;. Bull. Mus. Univ. State Missouri, I, 1884, p. 30, pl. 4, fig. 4—MiILier, North Amer. Geol. and Pal., 1889, p. 202, text fig. 215. The original description is as follows: Frond cyathiform in growing state; numerous bifurcating branches overlie each other, or are united at points of contact to form a network, with fine, more or less irregular, rhomboidal in- terstices. The branches unite at base into a slender axis which terminates in a bulbous root. The branches are usually less than one-fiftieth of an inch wide, and in some specimens short abrupt spinelike branchlets are given off. The texture is corneous. Only a few specimens have been obtained, except in fragments. Frond is about 2 inches high. It was first found by Colonel Grant in the Niagara limestones [near the base of the ‘* chert bed” at the * Jolly-cut ” ; 1884] at Hamilton, Ontario. k Fic. 52.—RHIZOGRAPTUS BULBO- Doctor Gurley’s notes on this species are —-8US SPENCER. THE TyPE-SPHC- oulp E IMEN. (AFTER SPENCER.) as follows: The description of 1884 adds that the axis is athecaphorous; that the strice along the branches (which vary in thickness from 0.25 to 0.3838 mm.) appear to mark the depressions of the common canal between the original positions of the polypites; that the thecal apertures have an ellipsoid form, and there are about 4 orifices in 1 mm.; and that on the side of the branch opposite the thece is a “ solid axis.” After a careful examination of Rhizograptus bulbosus, in which the pseudo- meshwork is well preserved, I can find no criteria to justify its generic dis- tinction from the Calyptograptus series, now that the basal ‘*‘ disk” has been found in the latter. While I would provisionally recognize Rhizograptus as a subgenus, I can not define it, and I think it probable that further study of large collections will lead to its entire suppression. The only difference I can see is a somewhat different aspect of the branches, which seem of a more rigid tex- ture, more knotty and zigzag-flexuous than any of the Calyptograptus species, 42 BULLETIN 65, UNITED STATES NATIONAL MUSEUM. Genus ODONTOCAULIS Lapworth. Odontocaulis LAPWoRTH, Quart. Journ. Geol. Soc. London, XXXVII, 1881, p. 175.—Pocta, Syst. Sil. Centre Boheme, VIII, Pt. 1, 1894, p. 171.— RUEDEMANN, New York State Mus., Mem. 11, 1908, p. 172. Doctor Gurley remarks on Odontocaulis as follows: This genus was thus established by Lapworth for forms which virtually com- bined two characters: (1) Absence of dissepiments, and (2) a polypiferous stem. Its only distinction from Dictyonema and Callograptus lay in these two features. But in O. occidentalis we find dissepiments along with the polypifer- ous stem. Whence there is now no generic distinction whatever between these two Odontocaulis species and the Callograptus species at the same horizon, except the single one of the thece on the stem. But it is not at all improbable that this is merely a question of better preservation, well-preserved stems being thecate. At least, of the two specimens of O. occidentalis, both showing the stem, one shows thece perfectly, the other only very obscurely. Having said this, however, a contingency may properly be noted. May it be possible that all the Callograpti at this horizon have thecate stems (in other words, all be referable to Odontocaulis) ? There is, I think, some ground for such a surmise. As Holm has said for Dictyonema, so now for Callograp- ius, the very great geologic range of the genus is a reason for suspecting the validity of the generic reference of the species. May it not then be possible that, compelled as we are for the most part to deal with and to base our species upon fragments of the meshwork, we are confounding two series; say, for illustration,“ a series lower Ordovician (Calciferous) in distribution, and a series upper Silurian (Niagara) in distribution, both sehies agreeing in type of meshwork (probably a character of subordinate biologic value), but differ- ing in characters of the base, At present there is nothing to negative such a view. Until we know the proximal portion of the type species (C. salteri) this reasoning must, of course, remain purely a possibility. But in a review like the present a clear outlining of future possibilities may be justifiable. Cer- tainly only under some such condition, it seems to me, would Odontocaulis stand much chance of ultimate retention. Its provisional retention I think advisable, pending a fuller knowledge of the condition of the base in the remaining Niagara Callograptus species. At present its most distinctive char- acters seem to be: Polypary arising from a single stem, which is expanded proximally into a “ disk,” and is thecaphorous along one side; distal branches more or less connected by dissepiments, Genotype—Odontocaulis keeping Lapworth. Llandovery, of Devils Bridge, Aberystwyth, Cardiganshire. ODONTOCAULIS GRANTI (Spencer). Callograptus granti SreNcerR, Canadian Nat., X, 1882, p. 165, nomen nudum ; Trans. Acad. Sci. St. Louis, IV, 1884, pp. 564, 571, 572, pl. 1, fig. 10: Bull. Mus. Univ. State Missouri, I, 1884, pp. 14, 21, 22, pl. 1, fig. 10.— JURLEY, Journ. Geol., FV, 1896, pp. 98, 308. The original description is as follows: Frond originating from a single stipe; branches slender, and bifureating two, three, or four times, and principally originating near the common radicle. “Yor illustration only, and as a pure surmise of the possibilities of the case,— R. R. Gurley. NN DENDROID GRAPTOLITES OF HAMILTON, ONTARIO. 43 In spreading gently above in undulations the branches are more or less parallel and situated closely together, and are connected occasionally with exceeding fine transverse bars. The texture is corneous, with the surface obliquely striated and marked with ellipsoid pits, which in some places indicate the orifices of the cells, of which there were about two for every millimeter of length of branch. The branches are rarely connected by minute crossbars. The general outline is that of a regular oval form, whose length, in the most perfect specimens, is 3 em. (be- sides the common stipe, which extends another centi- meter), and breadth, 2 cm. The branches are not more than a quarter of a millimeter broad, while the stipe is jy, Re SOG MTS about double that thickness. GRANTI (SPENCER). A This exceedingly beautiful frond in general appear- RHABDOSOME AND A BRANCH OF SAME EN- LARGED. (AFTER SPEN- CER. ) ance closely resembles C. salteri of the Quebec group but somewhat smaller, though there is some variation in the size of this species. Formation and locality.—This species occurs on the shaly surfaces of the Niagara dolomites at Hamilton, Ontario. Gurley’s notes are as follows: Of this species five specimens, certainly conspecific, were seen. The one figured in text figure 54 differs slightly from Spencer’s figure in having the branches somewhat more closely arranged, but in spite of this the identification seems to me almost certain. This specimen has about 50-55 branches in 25 mm. of width. The branches are about 0.25 mm. wide. The dissepiments would seem to have been some- what numerous; being very delicate, however, most of them Pic. 54.—OpoNTO- are covered or destroyed. eee aan A One specimen in the Spencer collection shows the basal INCoMpLEerR Stem and the proximal portion of the polypary. Dissepiments RHABDOSOME. are present. The basal stem bears two distinct thee at its summit and obscure indications of them below. It is some- what expanded at its lower end, appearing as though beginning to expand into a “disk.” C. granti then belongs to the Odontocaulis sec- tion, whatever may ultimately prove to be the taxonomic rank of that section. Horizon and locality.—Five specimens: One in Spencer collection, one in New York state collection, and three in U. S. National Museum collection; all five from the Niag- ara formation, Hamilton, Ontario. Plesiotype.—Cat. No. 55305, U.S.N.M. ODONTOCAULIS OBPYRIFORMIS Gurley, new species. This new species is based on a single specimen in !!8-55.—Opontocav- x i - oe LIS OBPYRIFORMIS, the Spencer collection, and is described by Gurley yew species. as follows: VIEW OF THE HOLO- TYPE SHOWING Polypary pyriform, broad end distal, 22 mm. long by 15 RHABDOSOME AND mm. broad, arising from a theeate stem extending about STEM RREARGHD. 2.5 mm. below the meshwork and there broken off; bearing three thee», intro- verted somewhat as in the Dicranograptide. Reticular portion of the polypary, 44 BULLETIN 65, UNITED STATES NATIONAL MUSEUM. arising at summit of stems by dichotomy, the branches likewise dichotomizing, the total number of divisions, including the primary, being five or six. In form they are U-shaped. Branches 0.8 mm. wide throughout, except at the extreme base where 4.0 mm. is reached. Peduncle 0.6 mm. wide. Branches set in the proportion of 27 in 25 mm. Dissepiments fairly numerous, being, in some places, as close together as 1 mm. Horizon and locality—One specimen from the Niagaran chert, Hamilton, Ontario. ODONTOCAULIS OCCIDENTALIS Gurley, new species. Gurley’s description and remarks upon this new species are as follows: Polypary pedunculate-cyathiform showing in both specimens an under layer separated by a “cliff” of rock from and exactly corresponding to the upper layer, as in Dictyonema, originating in a stem plainly thecaphorous, but not preserved as far down as the disk, with a virgula (7)° 0.2 mm. wide. Stem O.S mm. wide to the apices of the thecz; 0.6 mm. to the bottom of the depressions. Greatest height seen 88 mm., of which the stem takes up 11. Thece 40 in 25 mm. Polypary spreading Wy at once unilaterally, almost rectangularly, from the summit Y, of the stem and a little higher up for about 30° to the other Y side. Branches 0.4 mm. in diameter, flexuous, set rather dis- tantly and quite variably, but mostly about 25 in 25 mm. Dissepiments present, but few and remote. Thece visible in few places on branches. Besides the above characters, the figured specimen shows the basal disk, the initial dichotomous division at the summit of Te. RE apo the stem, dissepiments, and the cyathiform character of the TocauLIs oc- POlypary, the lower layer being visible underlying a “cliff” CIDENTAL- Of rock. On the stem I think I can trace thece, but they are IS, NEW SPE- too obscure to speak certainly. CIES. A RATH- ER COMPLETE Horizon and locality—Niagara chert, Hamilton, RHABDOSOME. Ontario Cc . Cotypes.—Cat. No. 55306, U.S.N.M.; Walker Museum, University of Chicago, No. 13514. Genus CYCLOGRAPTUS Spencer: Cyclograptus Spencer, Canadian Nat., X, 1882, p. 165, nomen nudum; Proc. Amer. Assoc. Adv. Sci., XX XI, 1883, p. 865; Trans. Acad. Sci. St. Louis, IV, 1884, pp. 563, 592; Bull. Mus. Univ. State Missouri, I, 1884, p. 42.—Mitier, North Amer. Geol. and Pal., 1889, p. 182.—GuURLEY, Journ. Geol., IV, 1896, pp. 94, 8309.—RUEDEMANN, New York State Mus., Mem. 11, 1908, p. 182. “Tt certainly bears some appearance of being a true virgula. Were the stem alone and the rock stated to be Lower Silurian, no one would hesitate to pronounce it a virgula. But as this is the only case in these Upper Silurian Dendroidea where I have seen any close resemblance to a virgula, doubt is but natural.—R. R. Gurley. DENDROID GRAPTOLITES OF HAMILTON, ONTARIO. 45 Spencer’s description of this genus is as follows: In this genus, the frond consists of a circular disk which was probably cup- shaped in its growing form, though flattened in a concave manner in the rock. From the radicle many stipes radiate through the noncelluliferous disk to its margin, and thence in a free manner to some distance beyond. The whole frond resembles a solid wheel, where the radiating spokes extend from the center regularly to beyond the circumference. The branches beyond the disk are cellu- liferous. The stipes have a central solid axis. The substance is highly corneous, though in some places replaced by pyrites. Doctor Ruedemann has reviewed this genus in his monograph, to which the reader is referred for comparisons between this and related genera. Genotype.—C yclograptus rotadentatus Spencer. CYCLOGRAPTUS ROTADENTATUS Spencer. Cyclograptus rotadentatus SPENCER, Canadian Nat., X, 1882, p. 165, nomen nudum; Trans. Acad. Sci. St. Louis, IV, 1884, pp. 565, 592, 593, pl. 6, figs. 6, 6a; Bull. Mus. Univ. State Missouri, I, 1884, pp. 15, 42, 48, pl. 6, figs. 6, 6a.—MILLER, North Amer. Geol. and Pal., 1889, p. 182, text fig. 162—Gur.LEy, Journ. Geol., IV, 1896, pp. 94, 309.—RUEDEMANN, New York State Mus., Mem. 11, 1908, p. 184, pl. 2, fig. 5. Doctor Spencer’s original description is given below: Frond circular, with numerous stipes radiating from a common center and projecting like a toothed wheel beyond the margin of a noncelluliferous disk. The frond was probably cup- shaped when growing, with the stipes projecting upward aye : 2 FiG. 57.—CYCLOGRAPTUS ROTA- like a row of spines or tent- DENTATUS SPENCER. COPY acles, but in the rock the fos- OF SPENCER’S FIGURE. sil is flattened and slightly convex. The stipes originate. in the center and are con- nected about half their length by their continuous non- EE eee CROC ORR AE: celluliferous membrane. Each stipes after passing beyond TUS RoTADENTaTUs their solid disk divide into two branches about halfway Spencer. A LArGe between their extremities and the margin of the disk. SPECIMEN FROM THE The branches or stipes are traversed by a central cylin- CLINTON GROUP, ; - zr ; CLINTON, N.Y. (AF. drical, smooth, solid axis surrounded by their common TER RUEDEMANN). canal, which is sometimes only represented by a central depression or elevation, but occasionally its form-is well preserved. The rarely indicated cell openings are represented by minute oval depressions in the substance. The texture is highly corneous. (or replaced by pyrites). The diameter of the frond is 2 em., and of the disk 1 em.; the radiating branches extend half a centimeter beyond the disk, and number between 25 and 30, but, as each is divided, the frond is surrounded by about 60 points. The branches (both through the disk and free portion) are rather over half a milli- meter broad, but the terminals are scarcely more than half that thickness and end in sharp points, 46 BULLETIN 65, UNITED STATES NATIONAL MUSEUM. Formation and locality.—This perfect little species was found in the dolomite of the Niagara formation proper, near the base of the series, at the quarry just west of the “ Jolly-cut” road at Hamilton, Ontario. Doctor Ruedemann has recently figured a specimen referred to this species, found in the upper part of the Clinton, at Clinton, N. Y. (See text, fig. 58.) Except in the matter of size, this example does not differ from the original type. Genus INOCAULIS Hall. Inocaulis Hatt, Amer. Journ. Sci. (2), XI, 1851, p. 401; Nat. Hist. New York, Pal., II, 1852, p. 176; 20th Rep. New York State Cab. Hist., 1868, p. 218 (rey. ed., 1868 [1870], p. 252).—NicnoLtson, Mon. Brit. Grapto- litidz, 1872, p. 181.—Spencer, Trans. Acad. Sci. St. Louis, IV, 1884, pp. 562, 588; Bull. Mus. Univ. State Missouri, I, 1884, p. 338.—MUILLEr, North Amer. Geol. and Pal., 1889, p. 193.—JameEs, Journ. Cincinnati Soc. Nat. Hist., XIV, Pt. 2, 1892, p. 161.—Pocra, Syst. Sil. Centre Bo- heme, VIII, Pt. 1, 1894, p. 197.—ELLES and Woop, Mon. Brit. Grapto- lites, Pal. Soe., 1903, p. xxxiv—RUEDEMANN, New York State Mus., Mem. 11, 1908, p. 185. Hall’s original description of this genus is as follows: A plantlike, corneous coral, with numerous bifurcating branches; structure fibrous or plumose. The texture of this coral is similar to the Graptolites, a black scaly crust or film being all that remains of the substance. From the specimens examined, it appears to have grown in groups, with rounded or flattened stems, which are dichotomous above and more or less spreading. The structure is too peculiar to be mistaken or to be referred to any established genus. Genotype.—Inocaulis plumulosus Hall. Niagaran of New York and Canada. The characters of both the genus and its type species have been discussed by Doctor Ruedemann in his monograph. INOCAULIS PLUMULOSUS Hall. - ” 9 Hatt, Rep. Surv. 4th Geol. Dist. New York, 1848, p. AGS heed: Inocaulis plumulosa Hatt, Nat. Hist. New York, Pal. II, 1852, p. 176, pl. 40G, figs. 2a, 2b; Geol. Surv. Canada, Can. Org. Rem., Decade 2, 1865, p. 18, fig. 26; 20th Rep. New York State Cab. Hist., 1868, p. 185, text fig. 28 (rev. ed., 1868 [1870], p. 215, text fig. 28).—NicHoLson, Mon. Brit. Graptolitidz, 1872, p. 132, text fig. 73. Inocaulis plumulosus Spencer, Trans. Acad. Sci. St. Louis, IV, 1884, p. 584, pl. 5, fig. 1; Bull. Mus. Univ. State Missouri, I, 1884, p. 34, pl. 5, fig. 1.—MILLER, North Amer. Geol. and Pal., 1889, p. 198, text fig. 183.— RUEDEMANN, New York State Mus., Mem. 11, 1908, p. 188, pl. 2, fig. 4; pl. T, figs: 25-2. -n 7 4 2} (a 8S Ale eet een, 0b DENDROID GRAPTOLITES OF HAMILTON, ONTARIO. 47 Doctor Gurley’s manuscript contains an elaborate description of this species, but the description and remarks published by Doctor Ruedemann are more to the point and are reproduced below: Hall has given the following diagnosis of this species: Stems flattened, dichotomous; structure fibrous or plumulose, apparently composed of imbricating elongated scales or fibers which spread equally on all sides. This coral is not abundant, though small fragments are frequently seen in the slab. It is very often replaced by iron pyrites, and where the surface Fie. 59.—INOCAULIS PLUMULOSUS HALL. A RATHER COMPLETE RHABDOSOME. is exposed to weathering, the fossil soon disappears so that it is only on freshly fractured surfaces that the structure is preserved. It is cited as occurring in the ‘* Niagara shale at Lockport, Rochester, and other places.” Spencer has recorded the form from the Niagaran limestone at Hamilton, Ontario. 48 BULLETIN 65, UNITED STATES NATIONAL MUSEUM. Gurley, in his manuscript, adds to the descriptions of Hall and Spencer in the following note: Two specimens from the Niagara formation, at Hamilton, Ontario, are figured, showing the blunt toothlike bodies and the apparently dentate mar- gin. While the appearance much resembles thece, it is impossible to make a positive statement on the material available. From a fairly large series of good specimens we derive the following data on this important species: The rhabdosome is arborescent in form; the branches divide dichotomously at irregular intervals, forming initial angles of 50°-60° but becoming later subparallel; of large dimensions (maximal length of largest fragment observed 14 em., width of another 17 cm.), the stem near base 5 mm. thick, the branches quite uniformly 38 mm. The branches diminish hardly toward the distal ex- Fics. 60—62.—INocAULIS’ PLUMULOSUS HALL. 60, PORTION OF A BRANCH, X 5; 61, DISTAL PORTION OF BRANCHES SHOWING TUBULAR BRANCHLETS AND IMPRESSIONS OF THEIR APERTURES; 62, TERMINAL PORTION OF A BRANCH. tremities which are bluntly rounded. The stem is apparently smooth, the branches are thickly set with short tubular processes which project about 1 mm. from the body of the branch, are of uniform width, directed upward and distally slightly bent backward and number, counted along the margin, about 14 in 10 mm. On specimens where the body of the branch has weathered away, exposing the apertures of the reverse side, they are seen to be distributed about equally over the whole branch, being approximately arranged in quincunx and numbering about five in the width of the stem. At the extremities of the branch they form dense tufts. Remarks.—The general habitus of 7. plumulosa can be best described by a comparison with a Lepidodendron or a Lycopodium; it not only resembles these plants in the mode of its branching and the uniformly wide, blunt ending branches, but also in their scaly appearance. Hall’s original and later improved figures give a good conception of the gen- eral appearance of the form. A more complete specimen from the Lockport { : { andes DENDROID GRAPTOLITES OF HAMILTON, ONTARIO. 49 limestone at Hamilton is here reproduced in text figure 98 [59] by a pen drawing made under Gurley’s supervision. In Plate II, figure 4 [text fig. 61] a portion of the same specimen which is partly weathered has been refigured to show the thece. Where in unweathered specimens the perisark is partly broken away [as in text fig. 60], the circular sections of the composing tubes ean be seen and the whole branch is found to be composed of apparently equal tubes. The rhabdosome, when more complete than in the specimens hitherto men- tioned, forms a dense mass of overlapping branches, which on account of the frequent dichotomies and later reapproachments of the branches assumes to some extent the aspect of a huge Desmograptus. We have been unable to see in any of our or Spencer’s rhabdosomes the central axis which he asserts to have observed in a number of specimens, and we doubt, from the general structure of this form, that such a thing as a central axis existed. Horizon and locality —The type is from the Niagara shale of New York, and the specimen here figured (text fig. 59) from the same horizon at Hamilton, Ontario. Plesiotype.—Cat. No. 54281, U.S.N.M. INOCAULIS RAMULOSUS Spencer. Inocaulis ramulosa SPENCER, Canadian Nat., X, 1882, p. 165, nomen nudum. Inocaulis ramulosus Spencer, Trans. Acad. Sci. St. Louis, IV, 1884, pp. 565, 588, 589, pl. 6, fig. 1; Bull. Mus. Univ. State Missouri, I, 1884, pp. 15, 38, 39, pl. 6, fig. 1—GurRtry, Journ. Geol., [V, 1896, pp. 99, 309. Fic. 63.—INOCAULIS RAMULOSUS SPENCER. COPY OF SPENCER’S FIGURE. The original description by Spencer is as follows: Frond consisting of numerous flattened bifurcating branches, originating in and radiating from a common radicle, composed of solid chitinous matter ; 50 BULLETIN 65, UNITED STATES NATIONAL MUSEUM. branches averaging 2 mm. in breadth for the larger and 1 mm, for the smalle1, toward the margin of the frond, where the branchlets end in two (sometimes three) extensions of unequal thickness. Texture corneous, with the surface composed of scaly fibers. ixtending longitudinally through the stipes are central or subcentral elevations (sometimes depressions), indicating a solid central axis. This species is described on two specimens, one of which shows the origin and base of the radiating branches, and the other the general frond, although the radicle is concealed. The extreme width of the typical specimen is 14 cm., and the height 8 cm. In general form this spe- cies differs from J. plumulo- sus in that the branches are more slender and rise regu- larly and more abundantly from the sides of the main stipes, which radiate from a common origin and do not consist of groups of individ- ual fronds. The radicle ap- pears to have been attached to some rocky surface in the sea, and not to have grown on some muddy bot- tom. The cell-bearing stipes appear to have had a com- mon canal, through the cen- ter of which was a central solid axis, as is also indi- cated in J. cervicornis. Formation and locality.— These specimens were ob- tained in the shaly dolomites, below the “ chert beds” of the Niagara formation at the “ Jolly-cut,’” Hamilton, Ontario. Fic. 64.—INOCAULIS RAMULOSUS SPENCER. SPECIMEN IN U. S. NATIONAL MUSEUM. Doctor Gurley’s notes are as follows: Polypary, in the single specimen seen, rising from a stem which gives off, in the proximal half of the portion visible, very few branches which, moreover, do not rebranch into a bushlike form, the bushlike branching occurring only in the distal half of the polypary. The only proximal branch distinctly seen bears a close spike of straplike processes (abortive branchlets?). Distally the polypary branches out bushlike, the main branches about 1 mm. thick. At or near the summit the branches subdivide into 2 or 8, usually unequal or sub- equal, terminal twiglets. The sides of the branches are usually slightly fringed ; the processes hairlike, few and remote’ The stems of this species remotely resemble those of Acanthograptus granti, but they are much more remotely and much more finely fringed, and in its ensemble this species has the branches less rigid and parallel than has A. granti. Horizon and locality—Niagaran (Lockport), Hamilton, Ontario. Plesiotype.—Cat. No. 55814, U.S.N.M. ee eS ee ee ee eee ee ee ee ee ee DENDROID GRAPTOLITES OF HAMILTON, ONTARIO. 5 INOCAULIS CERVICORNIS Spencer. Inocaulis cervicornis SPENCER, Canadian Nat., X, 1882, p. 165, nomen nudum; Trans. Acad. Sci. St. Louis, IV, 1884, pp. 565, 587, pl. 5, fig. 5; Bull. Mus. Univ. State Missouri, I, 1884, pp. 15, 87, pl. 5.—GuRLEy, Journ. Geol., IV, 1896, pp. 99, 308. The original description is as follows: Frond consisting of stipes having a common origin and rising above into a few stout, widely extended, bifurcating branches, averaging from 1.5 to 2 mm. in breadth, and terminating in dichotomous points of equal thick- ness; texture corneous, with a striated surface. Owing to the striations the appear- ance of the surface is that of rough scales or fibers, somewhat resembling the exterior portion of J. plumu- losus. In the growing state the branches appear to have _ been strengthened by longitudinal fibers— solid corrugations—and the cells to have been arranged vertically between FIG. 65.—INOCAULIS CERVICORNIS SPENCER. Copy OF SPENCER’S FIGURE. them. ing on both sides of the principal stipe at frequent irregular intervals, and dividing near their terminations into two stout branchlets (from 2 to i em: 52 BULLETIN 65, UNITED STATES NATIONAL MUSEUM. long), each ending in dichotomous free points. Texture corneous, with a sur- face apparently composed of scaly fibers. Of this species the fossils are not very well preserved. There is some indica- tion of a central axis. This species is easily distinguished from J. plumulosus by the close, regularly arranged, parallel branches from each side of the princi- pal stipes and by their terminal branches. The fronds appear to have grown in groups, but whether they are connected at the base or not is unknown. If not connected, the individual fronds (in the specimens under consideration) are about 4 em. high and 3 broad, with from 38 to 5 principal branches on either side of the central stipe (the branches are more numerous on one side than the other). The character of the cellules is unknown. Formation and locality.—Inocaulis phycoides occurs in the dolomitic lime- stones of the Niagara formation at the * Jolly-cut ” quarries, Hamilton, Ontario. A specimen doubtfully referred to this species occurs in the Na- tional Museum collections, but shows nothing in addition to the above. INOCAULIS DIFFUSUS Spencer. Inocaulis diffusa Spencer, Canadian Nat., X, 1882, p. 165, nomen nudum. Inocaulis diffusus Spencer, Trans. Acad. Sci. St. Louis, IV, 1884, pp. 565, 586, 587, pl. 5, fig. 4; Bull. Mus. Univ. State Missouri, I, 1884, pp. 15, 36, 37, pl. 5, fig. 4.—Guriry, Journ. Geol., IV, 1896, pp. 99, 308. This species was described by Spencer as follows: Frond originating in a single stipe at base, and rising above in numerous widely extended branches averaging about a millimeter in breadth, with dicho- tomous terminations; branchlets origi- \ 1h nating more frequently on one side ) r than on the other. Texture corneous, with surface more or less regularly striated, leaving in some places small oval impressions (probably the ori- fices of the cellules). Of this species I have seen only one good specimen (and two inferior fragments which probably belong here). The frond is 6 cm. high and of still greater breadth. One of the branchlets of the dichotomous termi- nation is much more slender than the other (a sort of lateral pustule), indicating probably the commencement of the growth of a new branch. The general form of this species is like J. bellus (Hall and Whitfield), but it is much larger in size, having more diffused branches, with an en- tire absence of prong-like processes from its sides. Formation and locality.—The type of this species was obtained by Colonel Grant, near the base of the “ cherty bed” at the “ Jolly-cut,”’ Hamilton, Ontario, in the Niagara dolomite. Fig. 67.—INOCAULIS DIFFUSUS SPENCER. Copy OF SFENCER’S FIGURE. a a es ee ee ee ee eS ee Perc! Cee ee ~ DENDROID GRAPTOLITES OF HAMILTON, ONTARIO. 53 Doctor Gurley has the following notes based upon a specimen (text fig. 68) referred to this species by him: The (fragmentary) polypary consists of a main stem the sides of which are beset with spinular processes similar to those found in Inocaulis. The branching is at an acute angle (about 35°). The main stem is about 0.8 mm. wide. The spinular processes are 0.5-0.6 mm. apart (too few are visible to state the number in 25 mm.). Besides these processes two others of a different character, 1 mm. long, are visible. They belong to the class regarded by Spencer as rudimentary branchlets. Both stem and branches are longitudinally striate, many distinct chitinous fibers being visible. Horizon and locality—Niagara limestone IIc. 68.—INOCAULIS DIF- FUSUS SPENCER. SPECI- and chert, Hamilton, Ontario. MEN DESCRIBED BY GUR- Plesioty pe.—Cat. No. 55315, U.S.N.M. LEY. INOCAULIS DIFFUSUS CRASSIRAMUS Gurley, new variety. Plate 5, figure 2. Fic. 69.—INOCAULIS DIFFUSUS CRASSIRAMUS, NEW VARIETY. HOLOTYPE. One specimen, which, judging from Spencer's figure and descrip- tion, seems to have the habit of J. diffusus, is described by Gurley as a variety as follows: Polypary consisting of numerous branches not widely radiating, 2 mm. wide ad maz.; the smallest seen about 1 mm. wide; longitudinally striated by very 54 BULLETIN 65, UNITED STATES NATIONAL MUSEUM. fine fibers; showing on the margins some blunt triangular processes, about 0.5 mm. wide and projecting about 0.5 mm. from the stem and about 1 mm. apart. Fiom the present material it would seem as though these processes form a somewhat less prominent feature than in J. diffusus and in I. walkeri, but this is somewhat doubtful. The principal difference between this variety and J. diffusus proper is the considerably greater thickness of the branches and the lesser prominence of the lateral blunt spines. The latter feature, however, may be a condition of preservation, and the former distinction may possibly be obliterated by a larger series of specimens. FHlorizon and locality—Niagara dolomite (blue building bed), Hamilton, Ontario. Holotype-—Walker Museum, University of Chicago, No. 13507. INOCAULIS CONGREGATUS Gurley, new species. A single specimen in the collection of the Walker Museum is the basis of this species, described by Gurley as follows: Polypary consisting of a number (about S in the type-specimen) of approximated and parallel stems, which are set 20 in 25 mm, transversely, and are simple for about 25 mm. Several bifurcate at this Fic. 70.—INOCAULIS CON- level; the central ones, however, bifurcate about 10 GREGATUS, NEW SPE- mm. higher up. Thickness of main stem about 1-1.2 cCIns. HOLOTYPE. a i mm.; of branches nearly the same (about 1 mm.). Thece obscure, the margins of the branches obscurely subserrate. Horizon and locality—Niagaran formation, Hamilton, Ontario. Holotype.—Walker Museum, University of Chicago, No. 13508. INOCAULIS ? STRICTUS Gurley, new species. Plate 2, figure 6. The description by Gurley is as follows: Branches rigid, not spreading, but up- ¥3 right and rather straight, bifurcating at a comparatively small angle (about 45°), diminishing in width from 2 mm. at the proximal end of the fragment to 1.5 (rarely to 1) mm. at the distal. Margins generally smooth, in one or two places subserrate. Successive bifurea- tions rather frequent (distant 5 to 10 mm,). AB Oe . + Fic. 71.—INOCAULIS ? STRICTUS, NEW SPE- Horizon and locality—Niagara ~ irs. Houoryre. (SEE ALSO PL. 2 chert, Hamilton, Ontario; one FIG. 6.) specimen (the type) in the Spencer collection, one specimen in Grant collection. ha etl ee et i F ees Tee ee ee ee | on toe I ec file tia ele a DENDROID GRAPTOLITES OF HAMILTON, ONTARIO. 55 INOCAULIS VEGETABILIS Gurley, new species. Plate 5, figure 1. Gurley describes this species as follows: A specimen in the New York State collection has the mode of growth charac- terizing J. phycoides, but is very much stouter in every way, the thickness of the stem and main branches reaching 6 or even 7 mm. and the terminal branches measuring 3 and 4 mm. Still it is not absolutely impossible that the difference may be merely one of age or distance from the point of origin of the polypary, but there is at present nothing to show that this is the case. The substance is in this case preserved in places, and forms a thick, coal- black film with longitudinal striations and furrowing corresponding to fibers and bands. No thece are visible. Horizon and locality —Niagaran (Lockport), Hamilton, Ontario. Holotype-—New York State collection. INOCAULIS ? THALLOSUS Gurley, new species. Plate 2, figure 5. Gurley describes this species as follows: Polypary 15 mm. long and 9 mm. in extreme breadth, consisting of a main stem about 1 mm. thick, from which proceed laterally at a little less than a right angle, branches about 0.6 mm. wide and about 5 mm. or less long The branches bifurcate about 1.5 mm. from the stem, and farther on redivide. Only a single specimen (obverse and reverse) of this species was seen. The species simply show as a stain (but a well-outlined stain) on the rock, with little or no evidence of graptolite structure. It is therefore possible that this species does not belong to the graptolites, but at any rate it seems to be new and is a part of the fauna. Horizon and locality.—Niagara limestone at base of chert, Hamil- ton, Ontario. Holotype.—Cat. No. 55316, U.S.N.M. The reverse is in the Spencer collection. Genus ACANTHOGRAPTUS Spencer. Acanthograpsus SPENCER, Canadian Nat., VIII, 1878, p. 461. ; Acanthograptus LAPworTH, Quart. Journ. Geol. Soc. London, XXXVII, 1881, p. 174.—SpPEeNcER, Trans. Acad. Sci. St. Louis, IV, 1884, pp. 562, 581; Bull. Mus. Univ. State Missouri, I, 1884, p. 31.—MiILLEr, North Amer. Geol. and Pal., 1889, p. 170.—RUEDEMANN, New York State Mus., Mem. 11, 1908, p. 191. The original description is as follows: Frond shrublike, consisting ef thick branches, principally rising from near the base, with little divergence and some bifurcations. One side of the branches is furnished with prominent spines or dentacles, which appear to mark the cell-apertures. Texture corneous and indistinctly striated. This 82651—Bull. 65—09 5 56 BULLETIN 65, UNITED STATES. NATIONAL MUSEUM. generic form resembles Dendrograpsus, but it is stronger and more bushy than species of that genus, and has conspicuous spines indicating a different cell structure [in whose axils the thecz were probably situated; 1884]. Gurley adds in his manuscript to Spencer’s definition of the genus: This is apparently a good genus, including several species which present a very similar facies, principally in the plumulose branches with a tendency to a 2- or 3-spicate termination. But if this genus be altogether distinct from Inocaulis (a point on which at present I do not feel positive), it is certainly here that Spencer’s Inocaulis walkeri belongs. Genotype.—Acanthograptus granti Spencer. Niagaran (Lock- port), Hamilton, Ontario. ACANTHOGRAPTUS GRANTI Spencer. Plate 2, figure 1; Plate 3, figure 4. Acanthograpsus granti SPENCER, Canadian Nat., VIII, 1878, pp. 458, 461, 462. Acanthograptus granti Spencer, Canadian Nat., X, 1882, p. 165; Trans. Acad. Sei. St. Louis, IV, 1884, pp. 564, 582, pl. 4, fig. 5; Bull. Mus. Univ. State Missouri, I, 1884, pp. 14, 32, pl. 4, fig. 5—Guruiry, Journ. Geol., IV, 1896, pp. 92, 308. The original description is as fol- lows: | Frond shrublike, with thick branches prin- cipally originating near the base. Some of the branches are bifurcated and have the ends dichotomous; cell apertures on one side only, and indicated by prominent spines which appear to be placed below them. The branches are sometimes the sixteenth of an inch broad, with spines in some places pro- jecting the twenty-fourth of an inch and ending abruptly. 72.—ACANTHOGRAPIUS GRANTI , : Bae iy ee S GaanD The larger fronds do not exceed two SPENCER. Copy OF SPENCER’S FIGURE: inches in height and sometimes have the same width. This species was first obtained [in the Niagaran dolomites; 1884] at Hamilton, Ontario, by Colonel Grant. The description of 1884 adds the following data: Surface longitudinally striated. Occasionally there are rudimentary denticles appearing ulso on the opposite side of the branch as well as on that marked with the regular spinelike projections, of which there are 6 or 7 in the length of a centimeter of the stipe, wliich is characterized by obscure indications of a solid central axis. The branches average a millimeter in breadth, and the spines are sometimes a millimeter long, which in some places extend into the material of the stipe to its center. The flattened frond is usually 4 or 5 em. high and about 4 wide, and consist of 15 or 20 branches at half its height, which are somewhat more numerous at the summit, owing to ocecasiona! bifurcations. The whole frond originates from a common radictie. ee DENDROID GRAPTOLITES OF HAMILTON, ONTARIO. 57 The best preserved graptolites that are found at Hamilton occur on the shaly surface of the limestone, but this species is only found in the highly crystalline rock, and consequently, although the general form of frond is well preserved and very beautiful, the detailed structure is not shown as well as in the forms that are found in the more perishable shaly rocks. Gurley adds the following: This species is easily recognizable among the now known Acanthograptus species by the very heavy branches, which very generally measure 1 mm. or a little more, though occasionally one as narrow as 0.8 mm. is seen. AS regards Fics. 73, 74.—ACANTHOGRAPTUS GRANTI SPENCER. 73, DISTAL PORTION OF RHABDO- SOME, X 5; 74, A NHARLY PERFECT RHABDOSOME. (AFTER RUEDEMANN.) number, they are set rather irregularly, but usually there are about 15 in 25 mm. of width. The specimens show no evidence of thece or of a virgula. Plesiotypes.—Cat. No. 55310, U.S.N.M. Specimen figured on Plate 2, figure 1, in Spencer collection. ACANTHOGRAPTUS WALKERI (Spencer). Inocaulis walkeri SPENCER, Canadian Nat., X, 1882, p. 165, nomen nudum; Trans, Acad. Sci. St. Louis, 1V, 1884, pp. 564, 585, 586, pl. 5, fig. 2; Bull. Mus. Univ. State Missouri, I, 1884, pp. 14, 35, 36, pl. 5, fig. 2.— GURLEY, Journ. Geol., IV, 1896, pp. 99, 309. Acanthograptus walkeri RUEDEMANN, New York State Mus., Mem. 11, 1908, pr 194. "pl. iG) figs: a, 25 pl. 7, fie. 4, text figs., 97, 98. 58 BULLETIN 65, UNITED STATES NATIONAL MUSEUM. Spencer’s diagnosis reads: Frond strong, with spreading branches, the margin having a plumulose ap- pearance; structure corneous, with a central axis, and the surface covered with minute points representing the cell-apertures. This frond somewhat resembles J. plumulosus, but it is slighter, and the branches (not exceeding 1.5 mm. in thickness) are much more numerous and proceed from a single stipe. The type specimen has a height of 8 and a breadth of 6 cm. Formation and locality—This species occurs in the Niagara limestones at Hamilton, Ontario. Doctor Gurley describes the species as follows: Polypary of general dendroid aspect; main branches mostly 1-1.5 mm. thick, a width of 2 mm. being only seen once, immediately below a_ bifurcation. Branching not very regular. Usually at the proximal end several branches 76 77 Fies. 76, 77.—ACcAn- THOGRAPTUS WAL- KERI (SPENCER). Fig. 75.—ACANTHOGRAPTUS WALKERI (SPENCER). Two FRAGMENTARY Copy OF SPENCER’S FIGURE. SPECIMENS. are somewhat clustered, and diverge thence radiatingly. On one specimen, which I hardly feel able to separate, the branching is rather more from a main axis. The branches, especially the main ones, are thickly beset (spinose- shaggy) with the long, blunt, obliquely upward-directed denticles, which are about 25 in the space of 25 mm. They differ much in appearance in different parts of the polypary, if, indeed, there are not more than one kind of them. Sometimes on the main stem they are blunter (about 1.0 mm. long and 0.75 mm. wide at base), while on the branches and branchlets they are less blunt. 3ut on the main stem and principal branches longer, narrower, and less rigid and regular and more hairy root-like processes occur, — — — — DENDROID GRAPTOLITES OF HAMILTON, ONTARIO. 59 This species can be told by the distinct and numerous “denticles ” on both sides of stem and branches, finer and less blunt dentate than in A. granti. Horizon and locality —Niagaran (Lockport), Hamilton, Ontario. Plesiotypes.—Cat. Nos. 54277, 55317, U.S.N.M. Fics. 78—80.—ACANTHOGRAPTUS WALKERI (SPENCER). 78, BRANCHES SHOWING BRANCH- LETS AND THECAL APERTURE, X 5; 79, A SPECIMEN NATURAL SIZE, ROCHESTER SHALE, New York; 80, FRAGMENT OF BRANCH, X 5, ROCHESTER SHAL®, New York. (79 AND 80 ARE AFTER RUEDEMANN.) ACANTHOGRAPTUS PULCHER Spencer. Plate 4, figure 5. Acanthograptus pulcher Spencer, Canadian Nat., X, 1882, p. 165, nomen nudum; Trans. Acad. Sci. St. Louis, IV, 1884, pp. 564, 582, 583, pl. 4, g. 6; Bull. Mus. Univ. State Missouri, I, 1884, pp. 14, 32, 33, pl. 4, fig. 6.—MiILtER, North Amer. Geol. and Pal., 1889, p. 170, fig. 128.— GuRLEY, Journ. Geol., IV, 1896, pp. 92, 308. The original description is as follows: This frond is broadly flabellate, but was possibly cyathiform in its growing state. Very numerous branches (with few principal subdivisions) arise from a common radicle and extend in an entirely free manner to the even and more or less circular margin of the frond. Along both sides of the branches many short rudimentary branchlets arise. Besides these, there are numerous spine- like processes, which possibly indicate the position of the cellules. The texture is corneous, with the surface striated, and in some places, where removed, there are indications of a lateral solid axis. From the center of the radicle the branches extend a distance of about 24 mm. [centimeters. R.R.G.] to the margin of the ground [frond. R. R. G.], or the diameter is about 5 mm. [centimeters. R. RR. G.]. The branches are half a millimeter thick. The rudimentary branch- lets, irregularly situated, are seldom more than 2 mm. long, and are stout, while the spinelike processes have a length of half a millimeter, and are about the same distances apart, befng very slender. The branches of this exceedingly beautiful frond (as I have only one complete specimen) appear to have occupied a semicircular position when alive, but in 60 BULLETIN 65, UNITED STATES NATIONAL MUSEUM. compression has so fallen as to extend nearly in the form of a circle. Though it resembles somewhat Callograptus niagarensis, yet the numerous rudimentary branchlets and spinelike processes distinguish it from that species. Formation and locality.—This species is found in the ‘“ chert-beds” of the Niagara formation at Hamilton, Ontario. The best specimen was obtained from Mr. Edward McLaughlin, of Hamilton. Gurley’s notes on this species follow: To this species I have referred, in all, sixteen specimens, several of the more fragmentary ones with some doubt. One specimen (PI. 4, fig. 5, text fig. 82) shows the base, and may be described as follows: Polypary (in this specimen) semicircular- flabelliform, originating in, and _ sessile upon, a transversely extended, apparently thick, fibrous, or discoid base of a black carbonaceous texture. From the base arise about three main branches, which bifur- cate and rebifurcate in their course toward the periphery, the resulting somewhat wavy branches running nearly straight out to the periphery, where they seem to termi- nate in two or several twigs or spikelets. Along their course their sides are beset with ‘‘rudimentary branchlets,’ ete., Fie. 81.—ACANTHOGRAPTUS PULCHER whose length may reach 1 mm. In this cae gee Copy or SPENCER'S FIG- cnecies, however, these lateral fringing processes are fine, giving the branches a feathered appearance. They never reach the thickness and remoteness of those seen in A. walkeri. The usual width of the branches is 0.4 mm., but some reach 0.5 mm. About 40 branches occur in 25 mm. of width, the interspaces thus being quite narrow. Only two thece are visible. These are 0.4 mm. apart (corresponding to about 60 in 25 mm.). Indica- tions of dissepiments are not wanting (some structures very much like them are visible), and although not entirely willing on strength of the present material, I may say that I incline very 83 Fics. 82, 83.—ACANTHOGRAPTUS PULCHER SPENCER. : 82, SPECIMEN PRESERVING BASE. (SEE ALSO PL. strongly to doubt their asserted 4, py¢. 5) ; 83, Less COMPLETE RHABDOSOME. absence in any of these genera, and also that in my opinion there is hardly a more dubious character than ‘absence of dissepiments.” For the assertion of such a condition the material must be absolutely irreproachable, as of all the structures in the polypary the dissepiments, being the most delicate, are the first to disappear. There can, I think, be no doubt that the present form is Spencer’s species. Both as a diagnosis by exclusion, and by its general agreement with his descrip- tion and figure, its identity is satisfactorily made out. Horizon and locality.—Niagara chert and glaciated chert, Hamil- ton, Ontario. Plesiotypes.—Cat. No. 55307, U.S.N.M. » DENDROID GRAPTOLITES OF HAMILTON, ONTARIO. 61 ACANTHOGRAPTUS CHAETOPHORUS Gurley, new species. Plate 3, figure 5. Gurley’s description is as follows: Polypary consisting of several main stems which may reach a thickness of 0.4 mm.; but principally characterized by very numerous, excessively fine, hair- like, more or less tufted fibers which fringe the sides of the stems and (?) also arise freely from the (invisible) base. Thee appear to be present, but are in- distinct. This species unquestionably finds its nearest affinity in Acanthograptus. It can hardly be a Dendrograptus, if that term be limited to forms taking origin from a Ai- single stem, as the form renders it very Fig. 84.—AcANTHOGRAPTUS CHARTOPE- probable that it grew in tufts from a ORUS, NEW SPECIES. HOLOLYPE- > (SEE ALSO Pu. 3, FIG. 5.) transversely extended base. Horizon and locality Niagara dolomite, Hamilton, Ontario. Holotype-——New York State collection. ACANTHOGRAPTUS MULTISPINUS Gurley, new species. The description by Gurley is as follows: Polypary flabellate-compressed, originating in and sessile upon a black, car- bonaceous, discoid base, from which the main branches arise, and then divide and subdivide, run outward, spreading some- what to both sides and being somewhat undu- late; 0.3-0.4 mm. wide; set about 25-30 in 25 mm. of width; their sides beset with processes of variable length and closeness. These proc- esses are in character intermediate between those of A walkeri and those of A. pulcher, being stouter, more rigid, and more distant Figs. 85, 86.—ACANTHOGRAPTUS than in the latter species, but less stout, less Geeta eee ae G ee rigid, and closer together than in A. walkeri. 85 By R. S. Basser.) Their lengths and closeness are too variable to be well reduced to measurements. The present species most nearly resembles A. pulcher, but in general has the branches more divergent, and with less tendency to parallelism; the fringing processes are stouter, more rigid, and more distinct, and the resulting appear- ance is less finely feathery. Horizon and locality—Niagara chert, Hamilton, Ontario. Cotypes.—Cat. No. 55309, U.S.N.M., and New York State collec- tion. 62 BULLETIN 65, UNITED STATES NATIONAL MUSEUM. Genus THAMNOGRAPTUS Hall. Thamnograptus Hau, Rep. Progr. Geol. Surv. Canada for 1857, 1858, p. 143, nomen nudum; Nat. Hist. New York, Pal., III, 1859, 1861, p. 519; 13th Rep. New York State Cab. Nat. Hist., 1860, p. 62; Can. Org. Rem., Decade 2, 1865, p. 141; 20th Rep. New York State Cab. Nat. Hist., 1868, p. 218 (rev. ed., 1868 [1870], p. 251).—NicHoLtson, Mon. Brit. Graptoli- tidze, 1872, p. 180; Ann. and Mag. Nat. Hist. (4), XVI, 1875, p. 270.— ZITtTeL, Handbuch d. Pal., I, 1879, p. 290.—SpPrencer, Trans. Acad. Sci. St. Louis, IV, 1884, pp. 563, 589; Bull. Mus. Univ. State Missouri, I, 1884, p. 89.—MiLitrr, North Amer. Geol. and Pal., 1889, p. 207.—Pocta, Syst. Sil. Centre Boheme, VIII, Pt. 1, 1894, p. 165.—BEiies and Woop, Mon. Brit. Graptolites, Pal. Soc., 1908, p. xli—RurEDEMANN, New York State Mus., Mem. 11, 1908, p. 204. This peculiar genus was founded upon two Ordovician species of graptolites, which have recently been studied by Ruedemann. The absence of thecz or apertures upon the branches has always kept the genus doubtful, and the following descriptions of the Niagaran forms can not be said to add anything to the knowledge of the genus. The original diagnosis is: Bodies consisting of straight or flexuous stipes (simple or conjoined at base?) with alternating and widely diverging branches; branches long, simple or ramose, in the same manner as the stipe. Substance fibrous or striate; the main stipe and branches marked by a longitudinal central depressed line, in- dicating the axis. Cellules or serratures unknown.°* Genotype-—Thamnograptus typus Hall (=Thamnograptus capil- laris Emmons). Normanskill shale, Kenwood, near Albany, New York. THAMNOGRAPTUS BARTONENSIS Spencer. Thamnograpsus bartonensis SPENCER, Canadian Nat., VIII, 1878, pp. 458, 462. Thamnograptus bartonensis Spencer, Trans. Acad. Sci. St. Louis, IV, 1884, pp. 565, 589, 590, pl. 6, figs. 4, 5; Bull, Mus. Univ. State Missouri, I, 1884, pp. 15, 39, 40, pl. 6, figs. 4; 5—QGurtury, Journ. Geol., IV, 1896, pp. 101, 309. - > o. The original description follows: Stipes single and broad with lineal undulating branches alternately arranged on opposite sides and having half the thickness of the stipe, which is as much as one-sixteenth of an inch broad. The branches which are given off are usually at right angles with the stipe; and are generally half an inch apart; there being an undulation of considerable length opposite to their place of attachment. Texture corneous and black, the surface being néarly smooth with longi- tudinal depressions. The branches are usually short and abrupt. They occur in the Niagara Limestone at Hamilton, Ontario, and the writer has seen them in the rock several inches long. Quoting from Doctor Gurley’s manuscript : The description of 1884 adds: Branches having half the thickness of the stipe, their bases nearly at right angles with it, but afterwards they bend up- ti i DENDROID GRAPTOLITES OF HAMILTON, ONTARIO. 63 ward; inserted on the stipe 1 fo 2 cm. apart. At point of origin there is usually a depression of considerable length on the side opposite to their place of attach- ment, and ay expansion on the same side. There is a strong medial depression, 0.5 mm. wide (marking a central axis?), extending through the stipe, which is 1.5 mm. broad. The specimens obtained are not entire. The branches are often widely separated, and are some- times long and flexuous, extending for several centi- meters in length. It sometimes happens that we obtain a long stipe which may be either a portion of the structure below the branches or a portion of a separate branch. Doctor Gurley further remarks: Altogether there are 9 specimens which I refer to this species. They vary considerably and tend to arrange themselves in two series, and at different stages in my werk I have rated them as separate species and as separate varieties. The latter is still the course I should prefer, if I could with any con- fidence correlate the two series in any definite way % FA eee ee eee : BARTONENSIS SPENCER. with Spencer’s species. But as I can not do so satis- Coprep FROM SPENCER. factorily, they are simply characterized as well as possible, and the task of connecting or separating them must remain to be worked out in the light of more complete specimens. I might, however, add that though there is no certainty in the matter I rather incline to believe these two series to represent widely separate fragments of the same polypary. Series A. Polypary (?) consisting of long, more or less straight, or flexuous stems, 1.25-2.5 mm., which for long distances are simple and destitute of branches. In the five specimens (on three slabs) plainly referable to this series, only two branches are seen. These branches are 88 89 about 1 mm. wide, and diverge from the main stem at about 60° or a little less. \ Texture brown-black, carbonaceous, exactly ss i similar to that of Jnocaulis plumulosa in ‘ the same beds. Series B. Fics. 88, 89.—THAMNOGRAPTUS BAR- TONENSIS SPENCER. Two ¥FRAG- d MENTS BELONGING TO SERIES B. Main stems and branches much narrower than in series A (stem ad maxrimum, 1.5 mm., usually 0.8, occasionally 0.6 mm. wide: branches mostly 0.5-0.8 mm. wide) ; branches more numerous, tending to diverge at a right angle or a little less. Texture the same as in series A. The specimens referred to series A belong to the Spencer collection and are not accessible at present. Those of series B are represented in text figures 88 and 89. @B.g., both with all of Spencer’s species, or either with any definite part thereof, I might perhaps add that a correlation of Series A with Spencer’s fig. 4, and of Series B with his fig. 5, seems somewhat plausible.—R. R. Gurley. 64 BULLETIN 65, UNITED STATES NATIONAL MUSEUM. Horizon and locality —Niagaran (Lockport), Hamilton, Ontario. Plesiotypes.—Cat. No. 55318, U.S.N.M. THAMNOGRAPTUS (?) MULTIFORMIS Spencer. Thamnograptus (7?) multiformis Spencer, Canadian Nat., X, 1882, p. 165, nomen EN: ; Trans. Acad. Sci. St. Louis, IV, 1884, pp. 565, 590, pl. 6, Hes. 2, 3; Bull. Mus. Univ. State Missouri, I, 1884, pp. 15, 40, pl. 6, figs. sai oe Journ. Geol., IV, 1896, p. 101. The rise description is as follows: Stipes simple, flexuous, and strong, usually divided into two (sometimes three) branches of equal thickness. From both the undivided and divided stipe a few short irregular branches originate at long unequal distances apart; and these may or may not end in two free points. The texture is corneous and black, with the surfaces somewhat striated and im- 91 pressed with a medial line (indicating a cen- tral axis?). In occasional specimens of the Same mode of branching, short spinelike proc- 90 esses, from one-half to one millimeter long and half a millimeter apart, probably indicate the position of the cellules on both sides of the branches. There is considerable variation in the size of these organisms. The larger specimens are 4+ or 5 em. long, and the stipes are usually about 1 mm. thick; however, some of the specimens, that I have referred here, have not more than half that size. In the 1 arger speci- lies. 90, 91.— THAMNOGRAPTUS ? mens the branches are usually about half a Paes SPENCER. COPIES centimeter apart. pee ie nae In the rocks of the Niagara formation nu- merous fragments of organism of the sraptolite family occur. Vast numbers, consisting of thick broken stipes, often flexuous, with one or two branches, or those with dichotomous terminations, are found, and can not be referred to any species described. Yet they so closely resemble the better specimens of this species that I have placed them here, although a further study might separate some of them from this species. Formation and locality. —Fragments of this species occur somewhat abun- dantly in the Niagara dolomitic rocks at Hamilton, Ontario. Of this species Doctor Gurley says: After many endeavors to recognize this species I have failed to find anything which I could confidently refer to it. As far as my experience goes nothing which has any definite structure resembles it. The only things which seem to approximate it are the most fragmentary specimens, too indefinite to be re ferred anywhere else. A perusal of Spencer’s description also leads me to suspect (but I do not assert it) that this species is not much more than a dumping ground for fragments. Certain it is that from time to time series after series of fragments (and at this horizon fragments are unusually and disproportionately numerous) otherwise unplaced were identified as this spe- cies, but eventually all except the worst were successfully referred elsewhere. This species must then stand on Spencer’s diagnosis and figure. DESCRIPTIONS OF PLATES. Unless otherwise stated, the views shown on these plates were prepared by R. S. Bassler.] 65 Figs. 1, 2. 66 . Dendrograptus ontarioensis, new species EXPLANATION OF PLATE 1. Page. Dendrograptus? problematicus Spencer-..--.....-----.------------ L0 (See also text fig. 6.) . A small rhabdosome, X 1.5, arising from a discoidal body. . A larger example, X< 1.5, showing the lax arrangement of the branches. . Dendrograptus ramosus Spencer- .------------------ 2. ie ee 8 (See also text figs. 3 and 9.) Gurley’s photograph of the specimen, X 1.5, illustrated on page 7. (See also text fig. 12, ) The type-specimen, X 2. U. S. NATIONAL MUSEUM BULLETIN NO. 65 PL. 1 NIAGARAN GRAPTOLITES. Fig. 1. EXPLANATION OF PLATE 2. Acanthograptys gran Spencer 25-22 62. oe ee ee eee (See also Pl. 3, fig. 4, and text figs. 72-74.) Gurley’s photograph of a specimen, 1.5, with the rhabdosome drawn in black. . Dendrograptus phamotheca; new. Species=---- += - = =.= se =e (See also text fig. 11.) A retouched photograph of the type-specimen, 3. . Dendrograptus praegracilis Spencer: 2 2.2 _- .22--. 925 sea (See also text figs. 4 and 10.) Photograph of the specimen illustrated in text fig. 10. . Dictysnema tenelum Spencers. fo. 0230 as ee eee eee eee (See also text figs. 82 and 33.) A small portion of a rhabdosome, X 2. « Unocaulis ?-thallosus, news Specles=. — 2 5-— sos ee eee eee ee eee The type-specimen, x 1.5. « Inocautis ? strictus, new species. =. 2. 25.2.5. eos eee ae eee (See also text fig. 71.) Photograph of the type-specimen, 1.5, by Gurley. 68 11 28 5d 54 i all i i U. S. NATIONAL MUSEUM BULLETIN NO. 65 PL. 2 NIAGARAN GRAPTOLITES. Fig. 1. . Dictyonema stenactinotum, new species . Acanthograptus grantt Spencer EXPLANATION OF PLATE 3. Dictyonema crassibasale, new species.....------------ he ee (See also text figs. 21-25. ) A portion of the rhabdosome, 2, figured in text fig. 23. (See also text figs. 34, 35.) View of the specimen, 1.5, illustrated in text fig. 35. . Callograptus strictus, new spetiess. 22.22 =2-- Sooo e = ae ee ee (See also text fig. 17.) The type-specimen, 2 (See also Pl. 2, fig. 1, and text figs. 72-74. ) Photograph by Gurley, with rhabdosome retouched in lack, . Acanthograptus aeons NeW. Species: 22-0 AS ee ee (See also text fig. 84.) Photograph of the type specimen, 1.5. 70 Page. 19 30 15 56 61 BULLETIN NO. 65 PL. 3 U. S. NATIONAL MUSEUM Sea NA WER CA SI eS: qe es Ae Ee. Fy 4 “ee e “ s b wy > Sa aie ty , » % ie et i oe on Ree R eas Wis Pk a n't st a ee : . ’ ee - ms _ 4 } a . ar Ute are A ee . i ae fhe a _ gee o “ied 5 . ~ ein eT | = NIAGARAN GRAPTOLITES. ; rie Now ee ROS 4 bh! on : To. a aon. EXPLANATION OF PLATE 4. | ] | Big. 1. Dichyonema, spencer, Mew Bpecies..- 5. = 25-222 -— ace == a= ee ee 36 | (See also text fig. 46.) | A portion. of the type-specimen, X 2. | 2. Dielyonema parallel, Dew SpeCles . =. -- 225 4. a. = ee de ees eee 37 | (See also text fig. 47. ) A te BS View of the distal half of the type-specimen. | (See also text figs. 41-43.) Photograph of a rhabdosome, < 2, showing the basal attachment. 4. Digtyorema polpnorphum Gurley oS 25 2-2 eee eee 24 (See also text figs. 26-29. ) Photograph of the original of text fig. 27, x 1.5. De eA ComtiOGroplLuUs prtlGR CTs PE CEN see a ets oe ae ee a9 (See also text figs. 81-83.) View of a rhabdosome, > 2, preserving the base. (2 U. S. NATIONAL MUSEUM BULLETIN NO. 65 PL. 4 NIAGARAN GRAPTOLITES. ee See rae. — wy ore . ee fs at f EXPLANATION oF Puate 5. Fig. 1. Inocaulis vegetabilis, new species ..---.----- ce gh LAIRD 5 Th ee A retouched photograph of the type-specimen, natural size. 2. Inocaulis diffusus crassiramus, new variety - - ---- - eon en beeen enneenees (See also text fig. 69.) \ Photograph of the type-specimen, natural size. 74 U. S. NATIONAL MUSEUM BULLETIN NO. 65 PL. 5 NIAGARAN GRAPTOLITES. INDEX OF GENERA AND SPECIES. {Synonyms are in italics. Numbers in heavy-faced type indicate the pages where descriptions are to be found. | d As | Page. Page. | Dictyonema ..........-.- 13, 14, 17, 18, 28, 38, 41, = Acanthograpsus ...-.2---------+--+--2+-2---- 59 crassibasale.. 19, 20, 21, 2 aon 29, 33, granti ....---------------:-- 56, 55 desmoidesaee eee ee $4, 35, 3 KCANtHOLTAPbUISs as sees shee ee Sac 55, 57, 61 Xa Ser eee 31, 32, 33 ehzetophorusiac- 4-52-62 61, 70 GPA S Sees ee a ie 34 STAM Geese .. 50,56, 57, 58, 68, 70 NGI eceneceastnd sae ween 93, 26, 31 multispinus.....-..-------- 61 GHAR ESS a Ae PP Ne 19, 23 pulehere sa ea-22- == 59, 60, 61, 72 GPACHIS. 3 oo a oo eee 19 WalKCL ea csccce scene 5, 57, 58, 59 gracilige se eco Meee ee ce 29 | PTANG Ese ak decks seek es 19 C. | parallelnr. 42.5.3 tee st a bos 37,72 (COMTO GMO SUS Ne mine fests tee Soke ce sa css oe aan ee 12 Percerassus .--.-------------- 31,35, 36 Callosraptshys-sscescceene eo ceoe eens 12, 40, 42 polymorphum ... 5, 24, 25, 26, 28, 30, 72 elec ans ieesanee ne ee eens 13 HELLO RMN Chee ce iat=r 5, 18, 19, 20, 26, 31 ORO RE RC ne eee 42 ELI OTIS ete = xara aia amas iottas 18 TIPS ae ee ee 14,15 | SPENCE Mess errr ser faites 2 == 36, 37, 72 MINUGUS Abs so sas5-e ees Se 15 splendens..--.....--.---------- 23 RMU GCA LiSht eee eat ee scee 13,14 StENACtINObMMisen-- soe eene ee 30,70 MUS AEDS seer ee epee ose 13, 14,59 | subretiforme...........-...-- 5, 26, 27 Ra LeTgem nese ret nore s 43 tenelld - ~~ +--+ +++ 2222222 eee eee 28 SERIO TH ore SEE eke ae 15, 70 Lene liege eee cers 25, 28, 29, 68 CAlPLOGRODSUS see aolsicne sire <1oaesioi2 ccs ; Pp. Ptilograpsus ...--.---.---- mates sre sie eters foliaceus . Philopraptus-...2-.---. saa Stee ce soeee fOlIBCCUS 4s = = iss ee ese se plumosus Te). Thamnograpsus bartonensis .........--- 16 Se Jaana nieeeeeees ~ ears bulbosas. Boer (?) multiformis.. ty DUS).