I MARINE BIOLOGICAL LABORATORY. Received J""'-'*''-^ / f.^ <^ Accession No. ^-^/^ Given by /^,>t-<^^:C-*y- ^::i-.^>^ ^i2^^^ Place. ^^?^<<^C^^...,..^.^^. . ***Tlo book ot< pamphlet is to be femoved from the Liab- opatopy inithoat the pepmission of the Tpustees. Committee on T'ubtication Barton W. Evermann Chairman and Editor C. Hart Merriam Frank Baker F. W, Hodge Henry Gannet PROCEEDINGS OF run Washington Academy of Sciences Vol. VII 1905 WASHINGTON June, 1905 -March, 1906 AFFILIATED SOCIETIES. Anthropological Society of Washington. Biological Society of Washington. Botanical Society of Washington. Chemical Society of Washington. Columbia Historical Society. Entomological Society of Washington. Geological Society of Washington. Medical Society of the District of Columbia. National Geographic Society. Philosophical Society of Washington. Society of American Foresters. Washington Society of the Arch.M OF THE LORICATI 77 terior mesenteric artery was not observed ; possibly, however, it was not injected. The posterior spermatic proper breaks up into numerous branches, which run along the posterior surface of the ovaries or penetrate the testes. The most posterior branch of the third spermatic artery is destined to supply the common oviduct or spermduct and sends off the anterior urinary bladder artery to the bladder. The posterior urinary bladder artery (PI. I, figs, i and lo ; Ur.B.A.) or the urinary bladder artery proper arises from the aorta directly behind the kidney, and in the specimen from which fig. lo was drawn, a renal artery was given off to the kidney. In addition to supplying the urinary bladder this vessel usually sends off a branch to the great lateral muscle. It is probably a modified haemal artery, (c) Comparisons of Hexagr amnios ^ Scorpcenichthys and Sebas- todcs. — In these 3 different genera there is not nearly as much variation in the distribution of the dorsal aorta as there is in the distribution of the cardinal veins. Hcxagrammos is identical with Ophiodon. In ScorpivnicJithys there are only 2 spermatic arteries, but what has been designated as the urinary bladder artery (PI. IV, fig. 29 ; Ur.Bl.A.) arises much farther cephalad than the corresponding vessel in Ophiodon, and may in part be homologous to the posterior spermatic artery of Ophiodon^ except that it does not supply the reproductive organs ; running along the dorso-caudal surface of the kidney it passes between the suprarenal bodies and sends off a branch to each of them. (It will be noticed that the suprarenal glands are located much further 'dorsad on the kidney than they are in Ophiodon.). Then passing ventrad the urinary bladder artery passes behind the posterior mesenteric vein to supply the posterior part of the urinary bladder, and usually it is continued still farther ventrad to supply the rectum. In Sebastodes several changes are intro- duced, which are caused by the presence of the air-bladder and anterior spermatic arteries. Where the anterior spermatic artery is given off in Ophiodon^ Hexagrammos and Scoi'pcBuichthys a similar vessel arises from the aorta in Sebastodes; this vessel, however, is destined to supply the air-bladder and is designated as the posterior air-bladder artery (PL IV, fig. 31 ; P.A.Bl.A.). In passing over the left side of the kidney it gives off several 78 ALLEN renal arteries and finally breaks up on the posterior end of the air-bladder. The single sperinatic artery (PL IV, fig. 31 ; Sper.- A.), which performs part of the function of the urinary bladder artery of Op/iiodon is given off from the aorta immediateh' in front of the point where the caudal vein penetrates the kidney. Near its source it sends off an intercostal arter}' (see fig. 31). It then follows along the posterior margin of the kidney, to the right of the caudal vein, and passing between the suprarenal bodies,^ supplies each with a branch. The spermatic artery then continues ventrad between the kidney and the reproduc- tive organs, gives off caudad the tirinary bladder artery (fig. 31, Ur.Bl.A.), which is the only artery observed for the bladder. When the genital organs are reached, the spermatic artery anastomoses with the 2 anterior spermatic arteries already de- scribed under the head of the mesenteric artery. VII. PERIPHERAL DISTRIBUTION OF THE VEINS. The veins in general follow their corresponding arterial trunks, but not so closely as they do the nerves. There is much less literature on the veins than on the arteries. In Se- lachians where it is so much more difficult to inject the veins this is not strange, but with the Teleosts no more difi^iculty is experienced in injecting the veins. Generally the whole venous system can be satisfactorily injected from one point. (See under paragraph on technique). I. Jugular Veins. These large sinus-like vessels (Pis. I and II, figs. 1,5, 15 and 16; J. v.), which are much longer than the corresponding common carotid arteries, arise in front of the prootic process from 3 principal trunks (see fig. 15). The external jugulars, coming from the facial region ; the internal jugulars, coming from the eye, eye-muscles, and brain ; and the orbito-nasal vein. Each jugular immediately enters the foramen formed by the prootic process and in its course through this foramen it is a rather small vessel lying directly above the external carotid 'The suprarenal l)odies are situated further caudad on the kidney than in Op/it'odon. BLOOD-VASCULAR SYSTEM OF THE LORICATI 79 artery, but upon emerging from this foramen rapidly increases in caliber. Then continuing caudad it passes over the efferent branchial arteries, and when the head kidney is reached follows along its ventral surface and terminates by anastomosing with the corresponding cardinal vein to form the great precaval trunk. Throughout its short course it receives numerous branches from the dorsal branchial muscles and the head kidney, which will be described in detail after considering the 3 princi- pal trunks which go to make up the jugular vein. {a) External Jugular Veins {^\^. I and II, figs, i, 5 and 15 ; Ex.J.V.). — Of the 3 vessels which unite to form the jugular vein this is the largest. It also arises from 3 rather large trunks, the largest of which is the facialis-mandilmlaris vein (Pis. I and II, figs, i and 12; F.Man.V.). This vessel has its source in the anterior part of the lower jaw^ from the genio- hyoideus vein (Pis. I and II, figs, i and 12; Ghs.V.), which runs along the ventral surface of that muscle just outside of the corresponding artery, which is a branch of the left hyoidean artery. The facialis-mandibularis vein at first passes along the inner side of the dentary bone, receiving numerous branches from the mandibular portion of the adductor mandibulse muscle. Shortly before leaving the articular bone it receives a large secondary mandibular vein, coming from the ventral side of the muscle, and a posterior branch coming from the inner side of the quadrate bone. The facialis-mandibularis vein then makes a dorsal bend ; leaving the corresponding artery it fol- lows up behind the ramus mandibularis V, or ramus maxillaris inferior of other authors, between the superficial and profundus portions of the adductor mandibular muscle, receiving several rather large branches from each. At the level of the levator arcus palatini muscle it receives, from the rear, the h3'oidean vein. Hyoidean Veins (Pis. I and II, figs, i and 12; Hyo.V.) — These vessels have their origin in the hyohyoideus superior muscles. Each vein runs along in that muscle some little dis- tance ventrad of the hyoidean arter}', which follows along on the surface of the arch. The vein receives a branch from the region of each branchiostegal ray and when the end of the arch 8o ALLEN is reached it curves cephalad, following along the interhyal, but above the minor hyoidean artery and the ramus h3^oideus. When the preopercular is reached the course of this vein is dorsad behind the ramus hyoideus and when a little past the middle of the preopercular, it passes with the nerve to the outer surface of the hyomandibular through a foramen between the hyomandibular and the preopercular. Here it receives a ven- tral branch from the posterior part of the adductor mandibul^e muscle, which follows along the outer surface of the preoper- cular. The main stem then leaves the hyoidean ramus and continues obliquely cephalad a little ventrad of the levator arcus palatini and between the superficial and profundus por- tions of adductor mandibulas, to unite with the facialis-man- dibularis vein. The combined trunk proceeds dorsad for a short distance between the ramus mandibularis V and the facial artery to the floor of the orbit ; where it receives the facialis-maxillaris vein. Facialis-maxillaris Veins (Pis. I and III, figs, i, 17, and 18; F.Max. v.). — Each of these vessels has its origin from a dorsal and a cephalic branch. The larger dorsal branch arises as an anastomotic vein from the orbito-nasal vein (see fig. 18) ; pass- ing beneath the nasal sac some little distance cephalad of the corresponding artery it receives at the level of the ventral surface of the nasal sac a rather large vein coming from the region of the palatine arch ; and then continuing ventrad a short distance the main stem passes under the maxilla artery and unites with the maxilla vein. The viaxilla vein (Pis. I and III, figs, i and 17 ; Max.V.) has its source in a superficial and a profundus branch from the premaxilla, which unite in the region of the vomer. In its caudal course it receives several branches from the anterior part of the adductor mandibulas muscle. After uniting with the dorsal branch from the region of the nasal sac the facialis-maxillaris vein proper crosses over the small facialis- maxillaris artery, and continuing caudad between the ramus maxillaris V or ramus maxillaris superior and the facialis- maxillaris artery in the adductor arcus palatini from which it receives several branches, it unites witii the combined trunk of the mandibular and hyoidean veins in the posterior part of the orbit to form the external jugular trunk. BLOOD-VASCULAR SYSTEM OF THE LORICATI 8 1 The facialis-maxillaris vein is much larger than the corre- sponding artery. It returns most of the venous blood from the region of the maxilla ; while it is the orbito-nasal artery, which furnishes this region with most of its arterial supply. The external jugular vein (Pis. I and II, figs, i, 5 and 15 ; Ex.J.V.) is in itself a rather short trunk. It follows along in front of the truncus infra-orbitalis or truncus buccalis-maxillo mandibularis and the external carotid artery in the posterior part of the orbit ; passing over the hyomandibular bone it unites with the orbito-nasal and internal jugular veins in front of the prootic process. (3) Internal Jugular Veins (Pis. I and II, figs, i, 13 and 15 ; In.J.V.). — What has been designated as the internal jugulars return the venous blood from the eye, recti muscles, and the brain. Each of these trunks might be said to have its source from the rectus, ophthalmic, and iris veins (see fig. 15) and at this point of union it also receives or sends off a large sinus-like vessel,^ which extends caudo-mesad in the eye-muscle canal and anastomoses in the median line with a corresponding sinus-like vessel from the opposite internal jugular vein. This horse-shoe shaped sinus incloses the encephalic artery and receives a pos- terior branch from each of the external recti muscles. The main internal jugular vein becomes greatly reduced in caliber in passing through what might be called the internal jugular foramen (a foramen between the alisphenoid, prootic, and para- sphenoid process, through which pass the internal jugular, the iris artery, and the ciliary nerve). Emerging from this foramen the internal jugular receives the encephalic vein, coming through the cranium through the small encephalic vein foramen (the most cephalic of the 3 foramina in the prootic, through which the encephalic vein and ciliary nerve pass). In front of the prootic process the internal jugular unites with the external jugular at an angle of about 75°. Coming in between these 2 trunks is the orbito-nasal vein, which might almost be said to unite with the internal jugular before it joins the external jugular. 'This connecting sinus may be the same as the cross vessel connecting the two Bulbi ophthalmic! described by Hyrtl (31, p. 236). Proc. Wash. Acad. Sci., June, 1905. 82 ALLEN Rectus Vein (PL II, figs. 13 and 15; Rec.V.). — This ves- sel arises from a ventral branch coming from the inferior rectus muscle and a cephalic branch coming from the superior and internal recti muscles. Its course is then dorsad between the optic nerve and the superior rectus muscle, and it unites with the ophthalmic and iris veins to form the internal jugular trunk. The vein from the external rectus muscle empties into the iris vein and will be described more fully in connection with that vessel. Ophthalmic Veins (Pis. I and II, figs, i, 5, 13, 15 and 19; Oph.V.). — Each of these veins carries off the venous blood, which has become collected in the choroid sinus. This sinus (PI. Ill, fig. 19 ; Chor.S.) is horse-shoe shaped, the anterior arm being much longer than the posterior one. It lies between the silver layer of the choroid and the similar shaped choroid ar- tery, and occupying a large part of the space between the optic nerve and the choroid gland, drains the entire choroid coat and also the ventral portion of the iris. The venous blood from the dorsal part of the iris is returned by the iris vein proper, w^hich will be described later on. The capillaries in the choroid may reach the choroid sinus in either of 2 ways. They may become collected into the choroid veins (PI. Ill, fig. 21 ; Chor. V.), which break up into a fine rete mirabile of venous capillaries which run parallel with the arterial rete mirabile capillaries, and these in turn become collected entad into larger venous vessels that empty into the choroid sinus ; or they ma}' reach the cho- roid sinus directly by what I have designated as the dorsal choroid vein or the 2 ventral choroid veins (PI. Ill, fig. 19 ; D.Chor.V. and V.Chor.V.), which empty into the anterior and posterior horns respectively. The vein returning the venous blood from the ventral portion of the iris is designated as the ventral or minor iris vein (PI. Ill, fig. 19; Ir.V.^j)). This vessel passes obliquely dorsad in the vascular layer of the choroid, directl}' cephalad of the ramus ciliaris brevis, and empties into the inner side of the anterior horn of the choroid sinus. No similar arter}' was observed and it is probable that the arterial supply for the ventral part of the iris comes from the ventral choroid arteries rather than from the iris arter}-. BLOOD-VASCULAR SYSTEM OF THE LORICATI 83 The ophthalmic vcm proper (Pis. I, II and III, figs, i, 5, 13, 15 and 19; Oph.V.) arises as a sinus-like vessel from the dor- sal region of the anterior horn of the choroid sinus, but grad- ually tapers down into its caudal course, and when immediately ventrad of the optic nerve receives a much smaller branch from the posterior horn. Curving around to the posterior side of the optic nerve it penetrates the silver layer of the choroid and the sclerotic coat. Once outside of the eyeball the ophthalmic vein pursues an oblique dorsal course, and, passing between the su- perior and external recti muscles it unites with the rectus and iris veins to form the internal jugular. Iris or Ophthalmic Minor Veins (PL II and III, figs. 13, 15 and 19 ; Ir.V.). — A single iris vein arises from the capillar- ies in the dorsal part of the iris. Together with the ramus cil- iaris longus and the iris artery it passes ventrad a short distance, between the silvery and vascular layers of the choroid (see fig. 19), and then penetrates the silvery layer and the sclerotic coat. After running along the posterior dorsal surface of the eyeball it passes between the superior and external recti muscles, but laterad to the ophthalmic vein. In its caudal course it receives a branch from the external rectus muscle, and finally terminates by uniting with the rectus and ophthalmic veins to form the internal jugular. Optic or Retina Vein (PI. Ill, figs. 19 and 20; Opt.V.). — In the specimen from which figs. 19 and 20 were drawn I noticed a small vein penetrating the sclerotic coat just ventrad of the optic artery. Its connection with the larger vessels had been destroyed before the vein was noticed, and internally the vein was not injected. Several specimens were injected espe- cially to demonstrate this vessel, but in every case this vein failed to become injected. It is probable, however, that this vein follows the course of the optic artery, returning the venous blood from the lens, falciform process, and the retina, and very likely empties into the ophthalmic vein. As has already been stated in the first paragraph under {p) the internal jugulars are connected with one another by a sinus- like vessel, which crosses the eye-muscle canal. Leaving the eye-muscle canal with the ciliary nerve and the iris artery. 84 ALLEN through what was designated as the internal jugular foramen, the internal jugular receives the encephalic vein shortly before uniting with the external jugular and orbito-nasal veins to form the jugular trunk. Encephalic Veins (Pis. I, II, and III, figs, i, 15, 23, 24, and 25; Enc.V.). — Each of these veins has its origin from 2 branches, an anterior and a posterior cerebral vein. The for- mer returns the venous blood from the cerebrum, anterior sur- face of the optic lobes, optic and olfactory nerves ; while the latter comes from the cerebellum, optic lobe, hypoaria, infundi- bulum, and the auditory region. Antcrio?' Cerebral Vein (PI. Ill, figs. 23 to 25 ; A.Cer.V.). — Cephalad, this vein arises from a small vessel running caudad along the ventro-lateral surface of the olfactory nerve, and re- ceives a branch from the olfactory lobe and one from the optic nerve. About midway between the olfactory and the optic lobes it unites with a much larofer vein from the cerebrum. This vessel arises from the inner parts of the cerebrum, and, passing laterad between the cerebrum and the optic nerve, considerably caudad of the corresponding artery, it unites with the small cephalic vein just described. The combined vessel continues caudad a short distance and when opposite the optic lobes re- ceives 2 or more branches coming from the anterior part of the hypoaria, i'nfundibulum, hypophysis, and the anterior surface of the optic lobes. Then curving obliquely cephalad, the ante- rior cerebral vein proper crosses the III and IV nerves and the posterior cerebral artery to unite with the posterior cerebral vein in forming the encephalic trunk. Posterior Cerebral Vein (PI. Ill, figs. 23 to 25 ; P.Cer.V.). — This vein has its source from 3 principal branches, namely: the mesencephalic, cerebellum and auditory veins, the 2 latter vessels uniting between the hypoaria and the optic lobes, im- mediately before the mesencephalic vessel is received. The auditory vein (PI. Ill, figs. 23, 23^ and 25 ; Aud.V.) arises from branches coming from the utriculus, anterior and external ampullae. The vein from the posterior ampulla empties into a branch of the posterior encephalic vein, and will be described under that vessel. Continuing cephalad for a short distance BLOOD-VASCULAR SYSTEM OF THE LORICATI 85 the auditory vein anastomoses with the ccrebclhtm vein (PI. Ill, figs. 23 and 25 ; Cer.V.), which arises in and leaves the cere- bellum with the cerebellum artery, but below it. In its ventral course it receives a superficial branch from the posterior surface of the optic lobe, and, after uniting with the auditory vein, the combined trunk continues cephalad a short distance between the optic lobe and the hypoaria and ventrad of the posterior cerebral artery before receiving the mesencephalic vein (See fig' 23). The mesencephalic vein (PI. Ill, figs. 23 to 25 ; Me. V.) arises from the floor of the mesencephalon (optic lobe) and penetrating ventrad through the crus, passes out between the optic lobe and the hypoaria, in front of the III nerve and mesencephalic artery, then crossing below the nerve and artery it unites with the common vessel formed by the anastomoses of the auditory and cerebellum veins to form \\\q. posterior cerebral vein (figs. 23 to 25 ; P. Cer.V.). The course of this vein is cephalad, directly below the posterior cerebral artery, between the optic lobe and hypoaria, and between the trigemino-facial complex and the IV nerve. Uniting with the anterior cerebral vein midway between the cerebrum and the optic lobe it forms the encephalic vein (Pis. I, II and III, figs, i, 15, 23 and 25 ; Enc.V.), which shortly leaves the IV nerve to follow trigemino- facial complex, and when the facialis portion of the ramus lateralis accessorius is given off the cranial cavity vein is re- ceived. This vein (PI. Ill, fig. 24; C.C.V.) follows along the anterior surface of this nerve and anastomoses caudad with a branch of the posterior encephalic vein, which follows along the posterior surface of the vagus portion of the ramus lateralis accessorius. Hence the venous blood from the adipose tissue of the cranial cavity may reach the jugular vein through the encephalic, or the posterior encephalic vein, or through both. Then leaving the trigemino-facial complex, along the inner surface of the ciliary nerve, the encephalic vein penetrates with it through the most anterior foramen in the prootic, and here empties into the internal jugular just before it unites with the orbitonasal and external jugular in forming the main jugular vein. {c) Orhito-nasal Veins (Pis. I, II and III; figs, i, 5, 13, 15, 86 ALLEX 17 and 18; O.N. v.). — Each of these veins has its origin directly behind the maxilla, and, following caudad along the ventral side of the corresponding artery, passes behind the nasal sac, where it receives 2 veins coming from the nasal sac. The smallest and most cephalic one is designated as the anterior nasal sac vein (PL III, figs. 17 and 18; N.S.V.^)). In the specimen from which figs. 17 and 18 were drawn this vessel arose from 6 anterior radial veins (see fig. 17). Each of these radial veins runs along the outer or distal edges of the secondary filaments of one of the primar}^ filaments, and from each of these secondary filaments there comes a branch, which receives the capillaries from the inner connective tissue layer of that secondary filament and from that portion of the primary or radial filament. These radial filament veins unite with one another at their bases and finally terminate in the anterior nasal sac vein, which empties into the main orbito-nasal trunk. In like manner the larger -posterior nasal sac vein (PL III, figs. 17 and 18; N.S.V.(2)) arises from 8 posterior radial veins, which take their origin from the secondary filament veins from their respective radial or primar}^ filament. The 2 nasal sac veins are usually distinctly separated as shown in fig. 17, but in a few cases I have noticed that they were connected by a longitudinal vein, thus forming a continuous lateral vein into which all the radial veins were emptied, and from which the 2 nasal sac veins had their source. Between these 2 nasal sac veins, the orbito-nasal vein anastomoses with a branch of the facialis-maxillaris vein (see fig. 18). After leaving the nasal sac, the orbito-nasal vein pursues a general caudal course, parallel with, but dorsad of, the orbito-nasal artery and mesad of the olfactory nerve, and enters the orbit through the olfactory foramen in the prefrontal. Once inside the orbit it leaves the olfactory nerve and the orbito-nasal arter}' to pursue, with the truncus supra-orbitalis or ramus ophthalmicus superficialis and profundus, a sort of dorso-caudal course through the orbit. Passing behind the superior oblique muscle it receives the inferior oblique vein (PL II, fig. 13 ; Inf.O.V.), coming up from the outside of that muscle, and the superior oblique vein (fig. 13 : Sup. O.V.), coming down from the inside of that BLOOD-VASCULAR SYSTEM OF THE LORICATI 87 muscle. Then continuing caudad, behind the superior rectus muscle and mesad of the truncus supra-orbitalis, it arrives in the posterior dorsal corner of the orbit, where it receives the scle- rotic vein (PL II, Hg. 15 ; Scl.V.). This vessel, which arises from the adipose tissue in the region of the anterior part of the eyeball, runs obliquely caudad across it, mesad of the corre- sponding nerve and artery. After receiving this branch, the main orbito-nasal vein crosses above the ophthalmic and iris vessels, and following around the eyeball for a short distance, finally comes in between and unites with the external and internal jugulars to form the great jugular vein. The remarks made under the summary of the carotids apply with equal force to the external and internal jugular veins. These are simply arbitrary names given to the 2 largest veins of the head region, which go to make up the common jugular trunk. 2. Vessels Empying Directly into the Jugular or into the Head Kidney. a. Veins Emptying into the Kidney, —These veins include the posterior encephalic and the first and second neural veins. They do not empty at once into the jugulars, but penetrate the dorsal surface of the head kidney, break up into smaller ves- sels, which become reunited forming the renal veins, and these empty into the jugular vein. Posterior Encefhalic Veins (Pis. II and III, figs. 16, 23 to 25; P.Enc.V.). — These veins may be said to concur in part with the first neural or vertebral artery. Each of these veins arises from a superficial capillary network from the dorsal sur- face of the optic lobes; passing caudad over the cerebel- lum it receives a superficial branch from it and several from the adipose tissue surrounding the brain and the semi-circular canals ; and usually anastomoses with the cranial cavity vein (see fig. 24), which empties into the encephalic vein. After passing over the cerebellum the posterior encephalic vein bends ventrad, following along behind the vagus portion of the ramus lateralis accessorius to its origin from the dorsal root of the vagus, and when the level of the oblongata is reached, 88 ALLEN sends off, or receives, a cross vessel from the corresponding vein on the opposite side. This cross vessel receives a branch, coming caudad along the dorsal surface of the oblongata. Whether it returns any of the venous blood from the cerebellum I was unable to determine. In the neighborhood of the origin of the vagus portion of the ramus lateralis accessorius from the dorsal root of the vagus, the posterior encephalic vein re- ceives an anterior branch or oblongata vein (PI. Ill, fig. 24 ; Obi. v.), which has its source from the side of the oblongata directly behind the roots of trigemino-facial complex, and shortly receives a branch from the posterior ampulla, then run- ning along the side of the oblongata, passes beneath the IX and X nerves and finally terminates by emptying into the posterior encephalic vein. Following along the dorsal root of the vagus nerve the posterior encephalic vein leaves the brain case through the vagus foramen in the exoccipital, but before leav- ing the skull the large myelonal vein is received from the rear. This vessel (PL III, figs. 23 to 25 ; My.V.) arises on the dorsal surface of the myel as far back as the 9th pair of spinal nerves. After running along on the dorsal surface of the myel for a short distance it separates into a right and a left myelonal vein. Each of these vessels runs along the lateral surface of the myel, passing between the dorsal and ventral roots of the spinal nerves, finally terminating by emptying into the posterior en- cephalic vein. Along its cephalic course the myelonal vein receives numerous vessels from the myel, and sends across dorsal connecting branches, which unite with the correspond- ing vein on the opposite side. Although the myelonal vein empties into the posterior encephalic vein, still, not all of its blood reaches the jugular through that vessel, but some of it is carried off by the first 3 spinal veins (Pis. II and III, figs. 16 and 24 ; Sp.V.). These vessels pass out with each alter- nate pair of spinal nerves, and emptying into the neural veins, which in the case of these anterior veins penetrate the dorsal sur- face of the head kidney, and here break up into ver}^ small veins, which again become collected into vessels that empty into the jugular vein. The posterior encephalic vein is simply a modified spinal vein, which after leaving the skull through BLOOD-VASCULAR SYSTEM OF THE LORICATI 89 the vagus foramen, follows along behind the nerve and receiv- ing the much smaller neural vein, penetrates the anterior dorsal corner of the head kidney (see fig. i6). Within the head kid- ney the posterior encephalic or the most anterior neural vein breaks up into very small veins, which again become collected and empty into the jugular vein. (/;) Veins Emptying Directly into the Jugulars. — Under this head belong the opercular and the 3 dorsal branchial muscle veins. The latter in addition to draining the branchial muscles receive also the dorsal nutrient branchial veins from the bran- chial arches. In Ophiodon these veins are always present, but vary considerably in their distribution. Perhaps the most common arrangement is shown in fig. i. Opercular Veins (fig. i; Op. V.). — These veins arise on the inner side of the operculars ; running dorsad behind the corresponding arteries, they curve ventrad, after leaving the dorsal edge of the operculars, and after receiving a branch from the levator operculi muscles of Vetter, empty into the jugulars a little behind the first dorsal branchial muscle veins. Dorsal Branchial Muscle Veins (fig. i ; Br.M.V, only the second vein being lettered). — In the specimen from which fig. I was drawn, the first of these vessels had its source in, and received its principal supply from, the first dorsal nutrient branchial vein (fig. i ; D.N.Br.V.). This vessel arises a little below the dorsal bend, and is at first the most anterior of the 3 vessels in the dorsal part of the first branchial arch. In the arch it receives a 7iutrient filament vein (fig. 2 ; N.Fil.V.), coming from the inner margin of each filament. When the dorsal bend of the arch is reached, the first dorsal nutrient branchial vein crosses over and continues dorsad behind the first efferent branchial artery. Then following along the outer surface of the first obliquus dorsalis muscle from which it receives a branch, it penetrates with the IX nerve through the first levator arc. branch, internus muscle, and again crossing over the first efferent branchial artery shortly after the carotid is given off, finally empties into the ventral side of the jugular a little cephalad of the opercular vein. The second dorsal branchial muscle vein, in this specimen, takes its source from the union 90 ALLEN of the second and third dorsal nutrient branchial veins. The combined vessel thus formed passes dorsad behind the second levator arc. branch, internus muscle, and after receiving a branch from it and another from the second obliquus dorsalis muscle, terminates in the jugular. In this specimen the third and last dorsal branchial muscle vein arose from 2 branches. The most cephalic one is a dorsal nutrient branchial vein from the last branchial arch, and the other has its source from the pharyngo-clavicularis externus, pharynx, and the occipito- clavicularis muscle. The dorsal branchial vessel thus formed passes in a dorso-cephalic direction above the corresponding artery. After crossing the last efferent branchial artery it receives a good-sized branch coming from the last 2 internal branchial levator muscles, and then empties into the jugular directly behind the second dorsal branchial vein, but before emptying into the jugular it receives the thymus vein from the rear. This vein (fig. i ; not lettered) runs cephalad along the ventral margin of the gland, receives several branches from it, and shortly before reaching the anterior end of the thymus, curves ventrad ; crossing over the posterior encephalic and jugular veins, finally terminates in the third dorsal branchial muscle vein shortly before the latter empties into the jugular. In another specimen from the one figured, the dorsal nutrient vein from the second branchial arch joined the first dorsal bran- chial muscle vein immediately after it had pierced the first levator arc. branch, internus muscle. The second dorsal branchial muscle vein took its origin from the third dorsal nutrient branchial vein and received branches from the third obliquus dorsalis muscle and the second levator arc. branch, internus muscle ; while the third and last dorsal branchial muscle vein had its source from the fourth nutrient branchial vein and a branch coming from the fourth obliquus dorsalis muscle. The thymus vein emptied into the posterior encephalic vein, and the vein from the phar3mgo-clavicularis externus, pharynx, and the occipito-clavicularis muscle, which is usually the source of the last dorsal branchial muscle vein, crossed the jugular and posterior encephalic veins and terminated in the thymus vein. ULOOD-VASCULAR SYSTEIM OF THE LORICATI 9I 3. hifcrior Jugidar Veins. These vessels return the venous blood from the ventral mus- culature of the head, heart, and ventral portion of the branchial arches and correspond in the main to the pharynx artery. The inferior jugular vein, however, does not become a paired vessel until near its termination in the precaval vein. The inferior jugular vein may be said to arise from a small vein coming from the ventral surface of the tongue, the lingual vein (PL II, fig. 12 ; Lin. V.). This vein continuing caudad as the inferior jugular vein, passes in a median line above and between the h3^ohyoideus superior muscles, after which it re- ceives 3 pairs of veins, the first pair coming from the outer posterior surface of the geniohyoideus muscles, the second from the inner surface of the hyohyoideus superior muscles (PI. II, fig. 12; Hys.V.), and the third pair are the ventral nuti'ient branchial veins from the first branchial arch. The latter ves- sels (PI. II, fig. 12 ; N.Br.V.) drain the ventral half of the first pair of arches. Each of them arises as a paired vessel in front of the first efferent branchial artery. The nutrient filament veins (PI. I, fig. 2 ; N.Fil.V.) from one side empty into one of these branches and those from the opposite side into the other branch.^ Further caudad these two branches unite forming a single nutrient branchial vein into which a few of the most ventral nutrient filament veins from both sides are poured. In front of this nutrient branchial vein, running along the cephalic margin of the arch, is another vein, which sends caudad cross- vessels that empty into the main ventral nutrient branchial vein. Continuing ventrad, cephalad of the efferent branchial trunk, the first ventral nutrient branchial vein empties into the inferior jugular vein. After collecting these veins the inferior jugular passes caudad, above the thyroid gland and the ventral aorta ; receiving branches from the gland, other ventral nutrient branch- ial veins, and several small veins coming from the obliqui ven- trales muscles. Emerging from the last pair of afferent bran- chial arteries the inferior jugular continues caudad, passing ' It is of interest to note that the nutrient filament veins comefrom the inner margins of their filaments ; while the nutrient filament' arteries are distributed to the outer margins. 92 ALLEN between the ventral aorta and the transversus ventralis muscle, and when the posterior edge of this muscle is reached, which is about midway between the last pair of afferent branchial arteries and the ventricle, the inferior jugular bifurcates into a very large 7-ight and a much smaller left htferio?' Jugular vein (PI. II, fig. 12 ; R and L.I.J.V.). The course of each of these veins is then obliquely caudad, running along the ventral side of the pharynx close to the pharyngo-clavicularis internus mus- cle. They terminate by emptying into their respective pre- caval veins. Throughout their course they receive branches from the pharynx, the phayngo-clavicularis' internus and ex- ternus muscles, and shortly before dividing, the inferior jugular received branches from the pharyngo-hyoideus and transversus ventralis muscles, and the coronary vein. The coronary vein (PI. II, fig. 12; Cor.V.) arises from a dorsal and a ventral branch, which run parallel with their respective arteries. The dorsal vessel collects the venous blood from the anterior part of the ventricle and the bulbus arteri- osus ; while the ventral branch drains only the bulbus. About midway between the ventricle and the first pair of afferent branchial arteries these 2 branches unite on the left side of the ventral aorta in forming the main coronary vein, which finally empties into the inferior jugular shortly after it emerges from the last pair of afferent branchial arteries. Beside this coronary vein, which drains the ventral aorta, bulbus, and anterior part of the ventricle there is another sys- tem of coronary veins, which terminate by emptying directly into the auricle. The outer layer of the ventricle is a mass of capillaries, which become collected on the ventral side into 4 or 5 veins that pass around to the dorsal side where some of them anastomose, forming 2 or 3 vessels, which penetrate the auricle close to the auriculo-ventricular valve. In one speci- men several small veins were noticed to arise on, and penetrate the dorsal surface of the auricle. In Sebastodes melanops^ beside the large right and the smaller left inferior jugular veins, 2 other veins, laterad to these, were observed. They arose from the pharyngo-clavicularis internus and externus muscles, and passed caudad to empty into their respective precaval veins. BLOOD-VASCULAR SYSTEM OF THE LORICATl 93 4. Ventral Veins. These veins correspond to, and drain the region supplied by the posterior part of the ventral artery: namely, the ventral or pelvic fins, their muscles, and the ventral portion of the myotomes forming the thoracic walls. Considerable variation is shown in these veins, since they may arise as 2 rather large veins of equal size or one small vein and one large one, but the most common arrangement for Ophiodon is that shown in fig. 12. The vessel designated as the right ventral vein (PI. II, fig. 12; R.Ven.V.) is a deeper vessel than the ventral artery, and terminates in the left hepatic sinus. This vein may be said to have its source from 2 branches, a I'ight and a left ventral fin vein (PI. II, fig. 12; R. and L.Ven.F.V.), which have their origin in the right or left ventral fin ray canal. In these canals the veins run behind the arteries, and receive a branch from the center of each ray. Leaving the canal of the last rays each of these veins crosses above the corresponding ventral ray artery, and passes cephalad, for some little distance, between the ventral or pelvic superficial adductor muscle and the ventral myotomes. Then after uniting with its fellow, the combined trunk continues cephalad as the right ventral vein or the main ventral vein. Along its course this vein and its 2 branches re- ceive numerous vessels. Soon after leaving the ventral fin canal, the left ventral fin vein receives a posterior ventral vein, which runs parallel with the corresponding artery. This branch receives several ventral intercostal veins (PI. II, fig. 12 ; V.- Intc.V.) from either side. In addition to receiving a ventral intercostal vein from the septum between each alternate pair of myotomes, each ventral fin vein receives several branches from the superficial and profundus adductor muscles, and at least 2 branches, coming up between the pelvic bones from the super- ficial and profundus abductor muscles. The right ventral vein itself also receives at least 2 ventral intercostal veins from the right side. In the specimen from which fig. 12 was drawn the left ventral vein (L.Ven.V.) was a very short vessel, arising from several ventral intercostal veins from the left side, but in other specimens the left ventral vein was as large as the right, and the vessel designated as the left ventral fin vein (fig. 12; 94 ALLEN L.Ven.F.V.) instead of uniting with the right ventral fin vein to form the right ventral vein, forms the principal venous sup- ply for the left ventral vein. In Hexagrammos and Scorpcetit'chtys the ventral veins are essentially the same as the last case described under Ophi'odon ; namely, the 2 ventral veins are of equal size, receiving their venous supply from the right and left sides respectively. In Scor;pcBnichthys, however, the right and left ventral fin veins do not leave the ventral fin ray canal with the artery from the last ray, as is the case with Ophiodoii and Hexagrammos^ but may leave the canal between any 2 rays, usually, between different rays in the 2 different fins. In Sebastodes these 2 veins are of equal size, but another condition is introduced. The 2 ventral fin veins leave the ventral fin canal with their respective arteries, anastomose, and the common trunk thus formed passes cephalad parallel with the ventral artery, between the two pelvic bones, and usually empties into the left ventral vein. 5. Subclavian Veins. In Ophiodon there are 3 subclavian veins, returning the venous blood from the region of the pectoral arch. Two of these, coming from the outer or abductor muscles, unite in forming the subclavian sinus which empties into the sinus veno- sus in front of the precava, while the third one coming from the rays and the inner or adductor muscles, pierces the anterior fork of the kidney. This vessel does not empty directly into the cardinal trunk, but first breaks up into smaller vessels, which reach the cardinal through the renal veins. Internal Subclavian or Subclavian VcinSf^^^ (PI. II, fig. 14; Sub.V.^,)). — The vessel thus designated, in the main, cor- responds with the internal subclavian artery. It receives its supply in part from the pectoral rays, and in part from the ad- ductor muscles, situated on the inner side of the pectoral arch. This vessel has its origin from a dorsal and a ventral pectoral fin vein, which unite in the pectoral ray canal, thus forming a continuous vessel, which runs along behind the corresponding pectoral fin artery. Within this canal it receives a small vein returning the venous blood from each ray. In no 2 specimens BLOOD-VASCULAR SYSTEM OF TilE LORICATI 95 did these 2 veins leave the pectoral fin canal in the same places ; in fact, they were not the same in the 2 different fins of the same fish. In the fin from which fig. 14 was drawn the dorsal branch left between the seventh and eighth rays, count- ing dorso-ventrad, and the ventral branch left in the neighbor- hood of the fourteenth ra)'. Each of these branches proceeded dorsad, for some little distance, along the inner surface of the superficial pectoral adductor muscle, and each branch received numerous smaller branches from the superficial and profundus adductor muscles. Uniting on the level with the scapula fora- men they form the internal subclavian trunk, which continues dorsad behind the subclavian artery. Shortly before the kidney is reached it curves caudad, and passing between the first few spinal nerves and the superficial adductor muscle, pierces the ventral surface of the corresponding fork of the kidney. Once within the kidney the internal subclavian rapidly decreases in caliber, by sending off branches that break up into capillaries, which finally reach the cardinal through the renal veins. The vein desijinated as the external subclavian or subclavian vein!^2) (PI- II> fig* 14 5 Sub.V.(.,)) has its origin from the super- ficial and profundus pectoral abductor muscles, on the outer surface of the pectoral arch. Coming through the scapula foramen, cephalad of the external subclavian artery, it re- ceives a branch from the profundus adductor muscle, and then runs for a short distance below and behind the precaval vein, where it receives the vein designated as the subclavian vein,^^) (PI. II, fig. 14; Sub.V.(3)). This vein takes its source from 2 branches, one coming from the ventro-cephalic portion of the profundus abductor muscle, and the other from the similar part of the profundus adductor muscle. The former penetrates the coracoid foramen, and unites with the latter in forming the main subclavian vein,^), which passes dorsad along the inner surface of the profundus adductor muscle. Leaving this muscle, subclavian vein^g^ unites with the external subclavian vein to form the subclavian sinus (PI. II, fig. 12 ; Sub.S.), which empties into the sinus venosus directly behind the precaval vein, but before uniting with the external subclavian, it receives a vessel formed from a branch from the clavicle and the slcrno- hyoideus vein (PI. II, figs. 12 and 14; Ster.V.). 96 1^ ALLEN In Hexagrammos and Scbastodes the subclavians are essen- tially the same as in Ophiodon, except that no vessel corre- sponding to subclavian vein(3) was observed. In ScorpcBuich- thys there were at least 3 internal subclavian veins (PL IV, fig. 30; Sub.V.(j-,); all of which broke up in the anterior fork of the kidney. The external subclavian vein in Scorpcenichthys (PI. IV, fig. 30; Sub.V.(^-)) instead of emptying into the sinus venosus, breaks up in the anterior fork of the kidney, cephalad of the internal subclavians. 6. Hepatic Portal System. This system of veins returns most of the venous blood from the stomach, spleen, casca and intestine. Some of the blood, however, from the posterior part of the stomach and intestine, reaches the right cardinal through the posterior mesenteric vein. This vein anastomoses with the portal system in at least two places. In Ophiodon there are 2 distinct portal veins, which terminate in the right and left lobes of the liver. The right portal returns the blood from the right side of the stomach, spleen, and a portion of the intestine ; while the left portal drains the ca;ca, ventral portion of the stomach, and a portion of the intestine. In Ophiodon these 2 systems remain quite well separated ; nevertheless, their branches anastomose in several places in the region of the posterior end of the stomach, but within the liver none of their branches unite. Each of the portals breaks up into capillaries in its respective lobe, which reunite in forming the right and left hepatic veins, and these vessels unite in a sinus before emptying into the sinus venosus. («) Right Portal Vein (PL I, figs, i and 2; R.Por.V.).— In Ophiodon the right portal trunk is in itself a ver}' short ves- sel, having its source from 2 principal trunks, one of them being the right gastric vein, coming from the stomach, and the other branch a vein formed by the union of the splenic and intestinal vein^i). The right gastric vein (fig. i, R.Gas.V.) has its origin in the posterior or cardiac portion of the stomach, where it anastomoses with branch Z of the posterior mesenteric vein (fig. I, P.Mes.V.) and the posterior gastric vein, which is a branch of the left portal. The course of the right gastric vein is BLOOD-VASCULAR SYSTEM OF THE LORICATI 97 cephalad, below the right gastric artery and the right gastric ramus of the vafrus. Throufjhout its course it receives numerous branches from the muscular coats of the stomach. Leaving the anterior part of the stomach it crosses above the corre- sponding artery and nerve, and the coeliac artery, and when about midway between the stomach and the caudal tip of the right lobe of the liver, directly behind a gland-like body marked G. it unites with intestinal vein ^y^. This vein (PL I, figs, i and 6 : Int.V.(,)) usually arises in the region of the rectum by anas- tomosing with branch Y of the posterior mesenteric vein (see fig. i). In its cephalic course in the adipose tissue surrounding the intestine, lying below the corresponding artery, it ordinarily sends off from one to 3 branches, w^hich empty into the right C£eca vein or its posterior gastric branch. In the specimen from which fig. i was drawn 3 such vessels were given off. The 2 posterior ones emptied into the right posterior gastric vein and the anterior one into the right casca vein. Through- out its entire course intestinal vein^i-, receives numerous branches from the intestine and when the spleen is reached, which is in the neighborhood of the anterior or duodenum portion of the intestine, it receives a large vein from that organ. The splenic vein (PL I, figs, i and 6; Spl.V.) arises in the center of the spleen from a fan-like system of vessels, which unite in a com- mon stem, that leaves the anterior part of the spleen with the splenic artery and soon empties into intestinal vein^j). Im- mediately after receiving the splenic vein, intestinal vein^i), usually, sends off or receives a connecting vein (PL I, figs, i and 6; C'.V'.), which unites with the anterior intestinal or duodenum vein, a branch of the left portal. In another speci- men this vein was seen to arise from the splenic instead of the intestinal vein. Intestinal vein(i) terminates by uniting with the right gastric vein, in the neighborhood of the right lobe of the liver, to form the main right portal trunk. As has already been stated this vessel (PL I, figs, i and 11 ; R.Por.V.) is in itself a very short trunk, which penetrates the apex of the right lobe of the liver, and exhausts itself in that gland by breaking up into numerous interlobular veins (fig. 11, I. Lob. v.), which finally terminate in numerous venous capillaries. Proc. Wash. Acad. Sci., June, 1905. 98 ALLEN Shortly before entering the liver, however, the right portal re- ceives a vein from a gland-like body, marked G in tig. i, and the anterior gall-bladder vein. The latter vessel (fig. 11, A. G.Bl.V.) arises from the anterior part of the bladder, and like the corresponding artery, anastomoses with the posterior gall- bladder vein. In some cases, as was also noted with the corresponding artery, intestinal vein^_, does not always have its origin in the rectum and anastomose with the posterior mesenteric vein and the vessels emptying into the right cseca. vein ; but sometimes arises much further cephalad, and the part of the intestine usually drained by this vessel was poured into the posterior mesenteric vein and the veins emptying into the right cseca vein, (d) Left Portal Vein (PL I, figs, i, 6 and 11 ; L.Por.V.). — This is somewhat the larger of the two portals. In Ofhiodon it has its source, principally, from the right and left pyloric casca veins and intestinal vein(2)- Of the 2 pyloric ccBca veins^ the right (PL I, figs, i and 6; R.Cae.V.) is the larger. Beside receiving 3 or 4 large branches coming from the c^eca it receives a right, and a left -posterior gastric vein (PL I, figs, i and 6 ; R, and L.P.Gas.V.). The right vessel comes from the right and ventral side of the posterior or cardiac portion of the stomach, where its branches anastomose with those of the right gastric vein and branch Z of the posterior mesenteric vein. In the specimen from which figures i and 6 were drawn the right posterior gastric vein received 2 branches from intestinal vein^) and the right pyloric caica vein received a third one. In those specimens in which these vessels unite with both intestinal vein^,^ and the right pyloric caeca vein or its posterior gastric branch it would be possible for the blood to flow in either direc- tion, but it is probable that the least resistance is toward the pyloric Ciiica vein. Shortly before the right pyloric cteca vein unites with the left in front of the pylorus, it receives a small vein from the pylorus. Usually the left pyloric cceca vein (see PL I, figs. I and 6), is much the smaller. It receives about 2 branches from the cseca and one or 2 small ones from the pylorus. Both of the pyloric ca?ca veins run outside of their BLOOD-VASCULAR SYSTEM OF THE LORICATI 99 corresponding arteries and unite in forming the left portal trunk directly in front of the point of bifurcation of the coeliac artery. Near its origin from the union of the two pyloric caica veins the left portal, or occasionally it is the right pyloric casca vein, receives intestinal vein^^^y This vein (PI. I, figs, i, 6 and ii ; Int.V.(„)) usually has its source from the ventral side of the intestine close to the rectum. Its course is cephalad in the adipose tissue below the intestine. Before going very far, how- ever, it crosses to the upper side of the intestine, changing places with intestinal vein(j). Then proceeding cephalad above the artery until the duodenum is reached, it crosses over the intestine, intestinal artery^j^ intestinal vein^^ the anterior part of the duodenum, the coeliac artery, and empties into the left portal close to its origin from the two pyloric caeca veins. Con- tinuing cephalad for a short distance between the stomach and liver and to the left of the coeliac artery, the left portal receives the anterior intestinal or chtodenuni vein (PI. I, figs, i and II ; A. Int. v.), which returns the blood from the anterior loop. The course of this vessel is at first directly behind the corre- sponding artery ; then after passing under intestinal artery(j) and intestinal vein^j^ it ordinarily gives off or receives the connecting vein (figs, i and 6; C.'V.'), a small vein which usuall}'- anas- tomoses with intestinal vein^j^ a branch of the right portal. Then after passing over the anterior arm of the duodenum from which it receives a branch, it crosses the coeliac artery, and after following along behind the hepatic artery for a short distance terminates in the left portal. The left portal enters the dorsal surface of the liver through 5 large radicals or terminal branches designated by the letters a to e (figs. 6 and 11). These vessels immediately penetrate the large left lobe of the liver and break up into the interlobular veins (fig. 11 ; I.Lob.V.), which, in turn, break up into venous capillaries. Usually several veins from the ventral surface of the stomach, designated as ventral gastric veins (fig. 6 ; V.Gas.V.), empty into some of these radi- cals, and some of the ventral gastric veins often penetrate the dorsal surface of the liver and break up into venous capillaries without emptying directly into the portal system. The -posterior gall-bladder vein (fig. 11; P.G.Bl.V.), which arises on the lOO ALLEN posterior dorsal surface of the bladder and anastomoses with the anterior gall-badder vein, empties into radical a of the left portal. This radical may also receive a similar, but smaller vein from the ventral surface of the bladder. An interesting vessel in Ophiodon is the left gastric vein (PI. I, figs. I and 6; L.Gas.V.), since it is not connected with the portal system but terminates directly in the precava. This vein has its origin in 2 branches from the left side of the stomach, on either side of the left gastric artery. The ventral branch is usually the larger ; arising from the extreme posterior end of the stomach, its branches anastomose with those of branch Z of the posterior mesenteric vein. When the anterior portion of the stomach is reached the smaller left gastric branch crosses over the left gastric artery and joins the main stem of the left gastric, and the combined vessel passes forward above the left gastric ramus of the vagus and empties into the precava. Still another small gastric vein arises from the anterior dorsal surface of the stomach and terminates in the precava, above the main left gastric vein. As in other vertebrates the intestinal, gastric, and caeca veins arise from capillaries in the connective tissue layer of the crypts and the larger branches run in the muscular layers. Within the liver the terminal branches or radicals of the two portals exhaust themselves in the intej'lobular veins (fig. 11, T.Lob.V.), which break up into venous capillaries, that reunite in forming the central or intralobtilar veins, from which the siihlobular veins (fig. 11, S.Lob.V.) have their origin. The latter vessels are the radicals, which by uniting, form the 2 /lepatic veins (fig. IT, R. and L.Hep.V.); which come from the right and left lobes respectively, and terminate in a Jicpatic sinus that enters the sinus venosus from the rear. In the liver the main trunks of the hepatic system lie beneath those of the portal system. As in the arteries, most of the variation of the veins in this group occurs in the viscera. Nevertheless, all of the species examined had a distinct right and left portal, which break up in the right and left lobes respectively. In Sehastodcs both portals terminate in a common portal. In HcxagraDinios the BLOOD- VASCULAR SYSTEM OF THE LORICATI lOI right portal anastomoses with radical a of the left portal. In Scorf<^nichthys this union sometimes occurs, but with Ophi- odon it has never been observed. However, both OpJiiodon and Scoj-pcEuichthys have a connecting vein that interlinks these 2 systems in the region of the spleen. {c) Right Portal in Hex agr amnios^ ScorpcBiiichthys and Se- bastodes. — In Hexagrammos^ as with Opkiodon, this vessel (PI. IV, fig. 27 ; R.Por.V.) has its origin from an intestinal, and a gastric vein. The I'ight gastric vein (PI. IV, fig. 27 ; R.- Gas.V.) is essentially the same as in Ophiodon, except that there is no posterior mesenteric vein for it to anastomose with on the apex of the stomach, and it runs on the opposite side of the artery from what it does in the other 3 genera. The vessel designated as intestinal vcin^^-^ (PI. IV, fig. 27 ; Int.V.(ij) is the principal intestinal vein. It arises in the region of the rectum, but soon crosses over to follow along the posterior arm of the ileum from which it receives several branches before receiving the splenic vein^ (fig. 27; Spl.V.), and another good-sized branch which drains the region supplied by intestinal artery (2). Passing cephalad, parallel with, but below the corresponding artery it crosses over intestinal vein(o), the anterior part of the intestine, the coeliac artery, radical a of the left portal, and when the stomach is reached unites with the right gastric vein to form the right portal {^g. 27, R.Por.V.), This vessel im- mediately passes under intestinal artery^,), between the coeliac and right hepatic arteries, along the posterior surface of the gall-bladder, but behind the right hepatic arter3^ Here it re- ceives a few small branches from the bladder and terminates in 2 or 3 small branches in the right lobe of the liver, and also anastomoses with radical a of the left portal. In Scorpcenichthys the right for tali^X. IV, fig. 29 ; R.Por.V.) has its source entirely from the right gastric and the splenic veins. All of the intestinal veins empty into the left portal. The right gastric vein (fig. 29, R.Gas.V.) is practically the same as in Ophiodon; arising in the cardiac end of the stomach, 1 In Hexagrammos the spleen is located much further caudad than is the case with any of the other genera studied. Its position is much nearer the vent than the stomach. 102 ALLEN it anastomoses with branch Z of the posterior mesenteric, and the posterior gastric veins. The sflenic vein (fig. 29, Spl. V.) leaves the anterior surface of the spleen, which is located directly above the pylorus, and passes forward to unite with the right gastric vein in forming the right portal, but immediately after leaving the spleen it receives the poste7-ior gastric vein (fig. 29, P. Gas. v.), which in Ophiodon emptied into the right cgeca vein, a branch of the left portal. The right portal, itself, is almost identical with the same vessel in Ophiodon ; it receives a small vein from a gland-like body marked G, and shortly before entering the right lobe of the liver receives the anterior gall-bladder vein which does not anastomose with the posterior gall-bladder vein as in Ophiodon. Usually the right portal breaks up in the small right lobe of the liver without anasto- mosing with terminal branch a of the left portal. Beside the ordinary branches which go to make up the right portal in Ophiodon, there is an additional one in Sebastodcs, namely, the anterior air-bladder or air-bladder retia mirabilia vein (PI. IV, fig. 31 ; A.Bl.V.). This vessel arises from the retia mirabilia venous capillaries, which are continuous with, and run parallel to, the corresponding arterial retia mirabilia capillaries. These venous capillaries unite in forming larger vessels that terminate in the main anterior air-bladder vein, which pierces the ventral wall of the bladder and empties into the right gastric vein. The latter vessel, as in Hexagrammos, has its origin in the posterior end of the stomach without hav- ing any posterior mesenteric vein with which to anastomose. Shortly after receiving the anterior air-bladder vein the right gastric receives the vessel designated as intestinal vein(i). This vessel (fig. 31, Int. V.(i)) arises in the rectum and drains the posterior portion of the intestine. In its cephalic course, par- allel with the corresponding artery, it follows along the poste- rior border of the spleen ; in Sebastodcs favidtis (fig. 33) it was seen to unite with the splenic vein as in Ophiodon, while in Sebastodcs auriculatus both vessels emptied separately into the right gastric vein. . Shortly before joining the right gastric, or splenic vein as it is in ►S'. JJavidus, intestinal vein^,) usually re- ceives a posterior gall-bladder vein (figs. 31 and 33, P.G.Bl.V.) BLOOD-VASCULAR SYSTEM OF THE LORICATI IO3 and an anterior intestinal vein. Soon after leaving the spleen, in front of the corresponding artery, the splenic vein (fig. 31, Spl.V.) receives the posterior gastric vein (fig. 31, P.Gas.V.) from the rear. This vessel arises from the ventral surface of the stomach immediately behind the pylorus, and receives a small branch coming from the ventral surface of the posterior end of the intestine. After receiving this branch the posterior gastric vein passes between the spleen and the ceeca and joins the splenic vein. The splenic v^ein in Sebastodes auriciilatus after crossing intestinal vein^^), and intestinal artery(2) unites with the right gas- tric component, directly below intestinal vein(,), to form the main right portal. Shortly before entering the liver the right portal receives a small branch coming from a gland-like body marked G (figs. 33 and 34), anastomoses with the common portal trunk (which will be fully described under the head of the left portal), and in its course in the right lobe of the liver receives the ante- rior gall-bladder v€v!\. This vessel (figs. 33 and 34, A.G.Bl.V.) is ahvays present, and sometimes returns the entire blood from the gall-bladder. Its course is to the right and above the ductus choledochus. id) Left portal vein in Hexagrammos, Scorpanichthys ^ and Sebastodes, — In Hexagrammos the two pyloric caeca veins are essentially the same as in Ophiodoti^ except that neither of them receives a posterior gastric vein from the cardiac end of the stomach. 'Close to its origin from the two pyloric ca^ca veins the left portal (PI. IV, figs. 27 and 28 ; L.Por.V.) receives a branch from the anterior arm of the ileum, designated as intes- tinal vein(^o) (fig. 27, Int.V.(2)), but which perhaps corresponds to an elongated anterior intestinal or duodenum vein. On the dorsal surface of the liver the left portal breaks up into 3 radi- cals (figs. 27 and 28, «, b and c). Radical a is prolonged to anastomose with the right portal, and soon after leaving the main stem receives a very large ventral gastric vein (fig. 28, V.Gas.V.), w^hich may to some extent take the place of the absent left gastric vein. In ScopcBnichthys the left portal (PI. IV, figs. 29 and 30; L.Por.V.) receives both of the intestinal veins. The pyloric caeca veins are essentially the same as in Ophiodon, except that I04 ALLEN the pyloric branch of the left one extends backward on the car- diac portion of the stomach as a sort of posterior gastric vein, and anastomoses with branches of the posterior mesenteric vein ; while the posterior gastric vein proper empties into the splenic vein instead of the right cajca vein as in Ophiodon. Intestinal vein^^s^ (fig- 29, Int.V.i-i^) arises from the posterior end of the iliac loop ; the most dorsal of its branches anastomoses with branch Z of the posterior mesenteric vein, and it receives a* branch coming from the region of the rectum. In its cephalic course, intestinal vein^j^ passes between the two arms of the ileum, and receives a branch from the posterior part of the in- testine designated as intestinal vein^^^ (fig. 29, Int.V.(2))> and the anterior intestinal or dtiodemun vein (fig. 29, A.Int.V.). The combined intestinal trunk thus formed passes under the anterior arm of the duodenum and joins the left portal close to its origin from the 2 pyloric caeca veins, but before emptying into the left portal it receives or sends off a connecting vein (fig. 29, C'.V.) that unites with the splenic vein. After reaching the great left lobe of the liver the left portal immediately gives off to each side numerous terminal branches or radicals, which break up into the interlobular veins. As in Ophiodon, except in a very few cases, radical a of left portal does not anastomose with the right portal; it, however, receives the posterior gall- bladder vein (fig. 30. P.G.Bl.V.), and also a very large ventral gastric vein (fig. 30, V.Gas.V.), which anastomoses anteriorly with the left gastric vein and posteriorl}?^ with a branch of the posterior mesenteric vein. As in Ophiodon there is a left gastric vein (fig. 30, L.Gas.- V.) emptying directly into the precava and two smaller left gastric veins ; one of which empties into the precava and the other into the left fork of the kidney ; while the main left gastric vein anastomoses with branches of the ventral gastric vein, which has branches that anastomose with branches of the pos- terior mesenteric vein. The left portal in Sebastodcs (PI. IV, figs. 30 and 31 ; L.- Por.V.) is a rather insignificant vessel, having its source from a vessel designated as intestinal vein^o, and the right pyloric creca vein. Intestinal vein^j) (fig. 31, Int.V.^,)) returns the BLOOD-VASCULAR SYSTEM OF THE LORICATI IO5 blood from the ileum ; passing beneath intestinal vesselS(,) and the splenic vessels, it crosses under the anterior part of the spleen, where it joins a common trunk formed by the union of the right pyloric C£eca vein and a very large j[)ylorns vein (fig. 32, Pyl.V.). The common trunk thus formed is the left portal, but instead of breaking up into numerous radicals it empties with the left pyloric cceca vein (tig. 32, L.Cae.V.) and the ventral gastric vein (fig. 32, V.Gas.V.) into the common fortal vein (fig. 32, C.P.V.). By anastomosing with the common portal, the right portal might also be said to empty into the com- mon portal. Stmimary of the Portals. — As in the case with the corre- sponding arteries, intestinal veins^ (,„,, ,) are arbitrary names given to the two principal intestinal veins. Considerable variation occurs in these two veins in the same species, but in O^hiodon the vessel designated as intestinal vein(2) arises in the posterior part of the intestine, and in its cephalic course along the ventral side of the intestine receives the splenic vein, and joining the right gastric vein forms the right portal. The corresponding vein in Hexagr aminos pursues a similar course ; while in Scopce- nichthys the two intestinal veins unite and empty into the left portal ; and in Sebastodcs intestinal vein^i^ drains only the pos- terior part of the intestine, and may unite with the splenic vein, or each of these vessels may empty separately into the right gastric vein to form the right portal. In every case the right portal breaks up in the right lobe of the liver. The vessel designated as intestinal vein(2) in Ophiodon arises from the ventral posterior end of the intestine and terminates in the left portal. In Hexagranmios this vessel might possibly correspond to an elongated duodenum artery ; while in Scorpcenichthys if this vessel is represented at all, it unites with intestinal vein^) and the combined trunk empties into the left portal ; and in Schastodes this is the principal intestinal trunk, arising from the iliac loop it unites with the right pyloric casca vein to form the left portal trunk. All the genera but Hexagrammos have a posterior gastric vein ; in Ophiodon it terminates in the right pyloric caeca vein ; while in ScorfcB7iichthys and Sebastodcs it empties into the splenic vein, a branch of the right portal. I06 ALLEN Ophiodon and Scor^(2nichthys have a left gastric vein, which empties into the precava ; while in Sehastodes and Hexagram- mos the ventral gastric veins are greatl}' enlarged, and evi- dently to some extent take the place of this vessel, nevertheless in ScorpcBuic/ithys the ventral gastric is a good sized vessel and anastomoses with the right gastric vein. In Ophtodon and ScorpcBuichlhys there is a grand anastomosis in the cardiac portion of the stomach of the branches of the right gastric, left gastric, ventral gastric, posterior gastric and posterior mesen- teric veins. Usually the right and left pyloric casca veins unite to form the left portal, but in Sebastodes the right pyloric caeca vein joins intestinal vein^^) to form the left portal, and the left pyloric caeca vein empties into the common portal trunk. Ophi- odon and Scorpcenichthys have a connecting vein in the region of the spleen that links the 2 portal systems ; in Ophiodon it usually connects intestinal vein^j^ with the anterior intestinal or duodenum vein ; while in ScorpcBuichthys it connects the splenic and common intestinal veins. Within the liver the 2 portals are usually distinctly separated in Ophiodon and in Scorpcenichthys ; while in Hex agr amnios radical a of the left portal anastomoses with the right portal ; and in Sebastodes both portals together with the ventral gastric and left pyloric caeca veins unite in forming a common portal trunk, which gives off numerous radicals that break up into the interlobular veins. 7. Renal Poi-tal System. Like the hepatic portal system the renal portal system con- sists of two principal venous trunks, which are connected by a system of venous capillaries within the kidney. One of these trunks, the caudal vein, arises in the region of the tail and pur- sues a cephalic course in the hasmal canal, immediately below the caudal artery, receiving the neural veins from above and the haemal veins from below. Piercing the dorsal surface of the kidney it bifurcates into a right and left renal portal vein ; each of these sends off numerous afferent renal veins that after breaking up into capillaries reunite in numerous efferent renal veins, which terminate in, and form, the right cardinal vein. This trunk starts in the posterior end of the kidney, passing BLOOD-VASCULAR SYSTEM OF THE LORICATI IO7 cephalad through the center of this organ ; it follows the right fork of the kidney and unites with the right jugular to form the right precava. Throughout its course it receives numerous branches, which will be described in detail later on. There is also a smaller left cardinal for the left lobe of the kidney, which will also be considered under a separate head. (a) Caudal Vein (PI. I, figs, i, 7, 8, 9 and 10; Cau.V.).— This trunk has its origin in the region of the last vertebra from a right and left branch ; both of which have a more superficial course than the corresponding arteries. The rig/it caudal vein (fig. 7, R. Cau.V.) is much the shorter; it arises from the region of the tail and passes cephalad between the super- ficial and profundus muscles, and when the last vertebra is reached, curves inward, and after receiving a dorsal branch joins the larger left caudal vein. The latter vessel (figs, i and 7 ; L. Cau.V.) has its origin from a dorsal and a ventral branch in the caudal fin ray canal. These branches lie immediately behind the corresponding lymphatic and arterial vessels. They receive a branch from the central canal of each ray, coming from the fin membrane and the fin ray muscles. Uniting be- tween the two hypural bones the dorsal and ventral branches form the left caudal vein (figs, i and 7, L. Cau.V.), which passes cephalad between the superficial and profundus caudal fin muscles, receiving branches from each. In the region of the last vertebra it receives a dorsal branch and curves inward to unite with the right caudal vein, but before joining the left caudal vein to form the main caudal vein, each of the caudal veins appears to receive a vessel from the caudal lymphatic sinus. The course of the caudal vein is cephalad in the haemal canal, immediately below^ the caudal artery; and in its course to the kidney receives a dorsal branch from in front of each alternate neural spine, and a ventral branch from in front of each alternate haemal spine. Each neural vein (fig. i; Neu.V.) has its origin from a . cephalic and a caudal branch ; the latter returns the venous blood from superficial and profundus levator and depressor muscles of that ray ; while the former returns the blood from the corresponding muscles of the preceding ray, and each I08 ALLEN branch receives a vessel coming from behind the ray. These 2 branches unite at about the level of the apex of the neural spine, forming the neural vein proper. At this point the neural vein receives the dorsal lateral vein (fig. i ; D.Lat.V.), return- ing the blood from the dorsal region of the 2 neighboring myo- tomes, and immediately after receiving this branch the neural vein passes obliqueh' ventrad between the neural lymphatic vessel and the neural spine. Then curving forward and out- ward it crosses the neural canal, the centrum, the dorsal aorta, and empties into the caudal vein. In crossing the vertebral column it receives a spinal vein, coming through the spinal foramen from the myel, and the median lateral vein (fig. i ; M.Lat.V.), returning the blood from the central region of the 2 adjacent myotomes. The harnal veins pursue a similar course from the ventral side of the body. Each of these vessels (fig. I ; Hee.V.) has its source from the superficial and profundus levator and depressor muscles of 2 successive anal rays. In the region of the apex of the hsemal spine it receives the ven- tral lateral vein (fig. i ; V.Lat.V.), coming from the ventral portion of the two adjacent m3'otomes. Then passing obliquely dorsad between the haemal lymphatic vessel and the haemal spine it empties into the caudal vein. This is the normal arrangement of a neural or a haemal vein ; occasionally, how- ever, a neural or a haemal vein may drain the region of 3 or even 4 myotomes, and a neural vein may cross either side of the vertebral column. Usually between the first and second caudal vertebrge the caudal vein receives the urinary bladder vein (figs, i and 10; Ur.B.V.), coming from the posterior sur- face of the bladder. Very often, however, as is shown in fig. 10, this vein does not empty into the caudal vein, but penetrates the posterior ventral end of the kidney and reaches the cardinal through the renal veins. After passing through the htemal canal of the first caudal vertebra the caudal vein curves ventrad and pierces the dorsal surface of the kidne}' and becomes tlie renal portal vein. Shortly after the caudal vein, or renal portal as it really is, penetrates the kidney it receives a rather large trunk designated as tlie posterior mesenteric vein (PI. I, figs, i and 10; P.- BLOOD-VASCULAR SYSTEM OF THE LORICATI IO9 Mes.V.). This vessel arises from 2 good sized branches designated as Y and Z (see fig. i). Branch Z which is strictly a gastric vein, takes its origin from several branches coming from the posterior or cardiac end of the stomach ; one of which anastomoses with the right gastric vein ; and 2 other branches anastomose with branches of the left gastric and posterior gas- tric veins. The course of branch Z is dorso-caudad ; passing to the left of the intestine and its vessels, it unites with branch Y directly below the reproductive organs. Branch Y, which is distinctly an intestinal vein, drains the posterior end of the intestine, and usually anastomoses with intestinal vein^,); pass- ing caudad it joins branch Z in forming the main posterior gas- tric stem, which passes between the reproductive organs, with- out receiving any branches, penetrates the posterior ventral surface of the kidney, and passing to the left of the right cardinal empties into the renal portal vein. It would be possible for the blood in the posterior mesenteric to flow in either direc- tion, but it is probable that the least resistance is toward the kidney. After receiving the posterior mesenteric vein the caudal or renal portal vein bifurcates into a right and a left renal portal vein or vena renalis advehens (figs, i and 10; Ren.P.V.). These trunks run cephalad for some little distance through the dorso-lateral part of the kidney, and gradually decrease in caliber by giving off numerous ventral branches, the afferent renal veins or venae renales advehentes (figs, i and 10, A. Ren. v.). These vessels break up into rather coarse venous capillaries near the lateral surface of the kidney, and become collected ventrad and mesad by the small efferent renal veins or venae renales revehentes (figs, i and 10 ; E.Ren.V.). A cross section through an injected kidney hardened in formalin shows us that these vessels, many of which are visible from the ventral side of the kidney, empty into the right cardinal from every direction. (3) The right cardinal vein (PI. I, figs, i, 5 and 10; R.Car.V.), which is the principal cardinal has its source mainly from the efferent renal veins ; it arises in the extreme caudal end of the kidney, below the caudal vein, and passes no ALLEN cephalad through the center of the kidney until the kidney forks, when it follows the right fork. In the region of the last branchial arch it unites with the right jugular in forming the 7-ight -precava (Pis. I and II, figs. 5 and 12 ; Prec.V.) or the diicUis Cuvierii as it is often called, which encircles the right side of the oesophagus and empties into the sinus venosus in front of the subclavian sinus. [c) Other Vessels Emptying into the Kidney. — Beside the posterior mesenteric and caudal veins there are several other vessels, which penetrate the kidney and reach the right cardinal in one way or another. First under this head might be mentioned the sper^natic veins. In the female (fig. i) numerous branches arise from the lateral surfaces of the ovaries and unite in a longitudinal vessel, that has its origin from the anterior surface of the urinary bladder and the oviduct. From this longitudinal vessel at least two spermatic veins (fig. i ; Sper.V.) have their origin ; passing dor- sad they terminate in one way or another in the kidney : they may empty directly into the right cardinal, or the renal portal vein, or they may reach the right cardinal through the efferent renal veins. In the male (see fig. 10) there is no longitudinal trunk, and the spermatic veins arise directly from numerous branches coming from the inner surface of the testes. In this specimen the most anterior spermatic vein emptied into an affer- ent renal vein, the second one broke up into capillaries, and the last 2 joined the posterior mesenteric vein within the kidney. The neiirals as in the caudal region drain the region of 2 m3'o- tomes, passing ventrad between the neural h^nphatic vessel and the neural spine, they penetrate the dorsal wall of the kidney, but instead of emptying directly into the right cardinal, break up into capillaries that reunite in the efferent renal veins. The intercostal veins (fig. i ; Intc.V.) corresponding to the haemal veins of the caudal region, arise from 2 myotomes of the thor- acic walls ; passing dorsad behind the intercostal lymphatic vessel they penetrate the ventro-lateral edge of the kidney, break up into capillaries, and reach the right cardinal through the efferent renal veins. In the cephalic part of the thoracic wall they anastomose ventrally with the ventral intercostal BLOOD-VASCULAR SYSTEM OF THE LORICATI III veins. Usually, there are 2 suprarenal veins (fig. 10, Sr.V^.), which pass inward and join the right cardinal. {il) The left cardinal vein (figs, i and 5 ; L.Car.V.) is a very short and unimportant vessel ; having its source entirely from the anterior end of the left fork of the kidney. The blood from the posterior part of this fork reaches the heart through the right cardinal. The left cardinal unites with the left jugular in forming the left precava, which passes around the left side of the oesophagus and terminates in the sinus venosus. {e) Renal Portal System in Scorpcenicht/iys, Hexagraninws and Sebastodes. — In each of these genera the renal portal sys- tem is in the main substantially the same. Some minor varia- tions are noted in the 3 following paragraphs. The renal portal system in Scorpienichikys is essentially the same as in Ophiodon. The caudal vein after passing through the haemal canal of the first caudal vertebra penetrates the dorsal surface of the kidney, and breaks up into two renal por- tal veins. As in Ophiodon di posterior mesenteric vein (fig. 29, P.Mes.V.) is also present, which arises from a gastric and an intestinal branch, and after passing over the urinar}' bladder from which it receives a branch, penetrates the posterior apex of the kidney, terminating in the renal portal ; but the distance it has to go cephalad in the kidney is much greater than in Ophiodon, and numerous branches are given off, which reach the cardinal through the efferent renal veins ; so that the pos- terior mesentric vein is much reduced in caliber upon joining the renal portal. It is of interest to note in this connection that in Enophrys and Calycilepidotus, 2 genera of the family Cot- tidae, no such vessel as the posterior mesenteric was noticed. As regards the spermatic veins, they are also of especial in- terest, coming in midway between Ophiodon and the peculiar arrangement found in Sebastodes. In the female there is a right and ?i left sperynatic vein (fig. 29, R. and L.Sper.V), each of which receives numerous branches coming from the lateral surfaces of their respective ovaries. From each of these longi- tudinal veins there arise a cephalic and a caudal vessel ; both of which unite with corresponding vessels from the opposite side to form the spermatic veins proper (fig. 29; Sper.V.j ^^j,)' ^"^ 112 ALLEN each of these veins empties directly into the right cardinal, which in Scorfmnichthys runs along the ventral surface of the kidney. In both male and female the right and left spermatic veins are continued some little distance cephalad of the reproductive organs, and empty into their respective cardinal veins, a little behind the point of union of the cardinals with the jugulars to form the precava. The caudal vein (fig. 27 ; Cau.V.) in Hexagramnios after passing through the first caudal vertebra gives off an anterior and a -posterior renal portal vein (fig. 27 ; Ren.P.V.) The former is the principal renal portal vein ; it continues cephalad along the dorsal surface of the kidney, and breaks up into numerous afferent renal veins. In one specimen this vein appeared to empty directly into the right cardinal vein. The smaller posterior renal portal breaks up in the caudal end of the kidney. One of its branches receives the vein designated as the urinary bladder vein (fig. 27 ; U.Bl.V), which may to some extent be analogous to the posterior mesenteric vein of Ophio- don and Scorpcenichthys ; it has its source from a meshwork of small veins on the rectum, which anastomose with branches of intestinal vein^j^ ; passing across and along the dorsal surface of the bladder from which it receives several branches, it pierces the ventro-caudal end of the kidney, and gives off several branches in the kidney before uniting with a branch of the renal portal. The right cardinal (fig. 27 ; R.Car.V.) as in the other genera arises in the extreme posterior end of the kidney, and passing cephalad close to the ventral wall, unites with the right jugular in the right fork of the kidney to form the right precava. The veins from the caudal region of the ovaries empty into a longitudinal vessel that passes between the ovaries ; farther forward this vein bifurcates, one branch running along the dorsal surface of the left ovary and the other along the right ; both of them receiving numerous branches from the lat- eral surfaces of their respective ovaries. From the right longi- tudinal spermatic vein there arise an anterior and a posterior branch, both of which unite with the corresponding branches from the left longitudinal spermatic vein in forming the main anterior and posterior spermatic veins (fig. 27, Sper.V.^,) ,^,„, fo)) which empty directly into the right cardinal. BLOOD- VASCULAR SYSTEM OF THE LORICATI II3 All species of Scbastodcs examined had a distinct renal por- tal system, which in the main resembled Ofhiodon; however, the renal portal veins extend much further cephalad, there is always one or more posterior air-bladder veins emptying into the renal portal system, and there is no posterior mesenteric vein. The kidne}^ itself differs considerably in shape from that of the other genera ; while it usually occupies a large portion of the dorsal part of the short thoracic cavity, still a large por- tion of the organ is crowded cephalad into the two forks. The caudal vein (PL IV, fig. 31 ; Cau.V.) after piercing the pos- terior dorsal side of the kidney continues cephalad along the dorsal surface of the kidney for some little distance as a renal ^07-tal vein and not until the kidney forks does this vein sepa- rate into the renal portal veins (fig. 31, Ren.P.V.). These veins continue cephalad in their respective lobes until near the point of union of the cardinals with the jugulars, giving off numerous afferent renal veins, and the renal portal itself re- ceives the following vessels. First, the spermatic vein (fig. 31 ; Sper.V.), which is formed from the posterior union of the right and left spermatic veins. In its dorsal course about midway between the reproductive organs and the kidney it receives the urinary bladder vein (fig. 31 ; Ur.Bl.V.), and immediately be- fore emptying into the renal portal, a small suprarenal vein. Shortly after receiving the spermatic, the caudal or renal por- tal receives a rather large posterior air-bladder vein (fig. 31 ; P.A.Bl.V.), which arises from a regular network of vessels on the posterior end of the air-bladder. In the specimen from which fig. 31 was drawn, two smaller posterior air-bladder veins were also noticed ; one of which terminated in the renal portal vein, and the other in the right cardinal. Usually, how- ever, there is but one posterior air-bladder vein, and it may empty into either the right cardinal or the renal portal vein. The right cardinal is almost identical to the similar vessel of the other genera, and a description of it is unnecessary. VIII. VASCULAR SYSTEM IN AXOPLOPOMA. Three specimens of this species were brought in by Chinese fishermen when this paper was about finished. All were in- Proc. Wash. Acad. Sci., June, 1905. 114 ALLEN jected, but only one satisfactorily, the other specimens having been badly torn by the hooks. Upon dissection several interest- ing variations were noticed, and it seemed desirable to include a representative of the family Ano^lo^omatidcB in this paper. Carotid Ar/cries. — In Anoplopoma there are no common carotids ; both carotids arise separately from the dorso-cephalic corner of the first efferent branchial artery. The internal carotid (fig. 35 ; I. Car. A.), which is given off first, presents no peculiarities. While the external carotid (fig. 35 ; E.Car.A.) is a much smaller vessel than in the other genera, and simply supplies the facial region without anastomosing with the hyoi- dean artery to form the mandibular artery ; it immediately gives off the vessel designated as the -pseudobranchial or afferent ■pseiidobranchial artery (fig. 35 ; Ps.A.), which is as large as the external carotid, and which might be said to arise with the external carotid from the first efferent branchial artery. The course of the pseudobranchial artery is ventrad behind the hyo- mandibular, exhausting itself by giving off numerous afferent pseudobranchial filament arteries. Near its distal end the pseudobranchial artery receives the dorsal branch of the hyoi- dean artery, and it is probable that the hyoidean arter}^ furn- ishes the pseudobranch, especiall}^ the ventral part of it, with some of its blood supply, but most of it evidently comes from the pseudobranchial artery, which is much larger at its source from the external carotid than at the point of anastomosis with the hyoidean arter3^ This arrangement somewhat resembles the pseudobranchial supply in Gadus, according to IMliller (50) and Parker (61), but differs from it considerably. In Gadus the afferent pseudobranchial artery is a branch of the h3'oidean artery, and the dorsal continuation of the main stem, which is much reduced in caliber, anastomoses with the internal carotid of the circulus cephalicus. Hyoidean Arteries (fig. 35 ; Ilyo. A.). — One of the most strik- ing differences in the circulator}^ system of Anoploponia is in connection with this vessel. As in Ophiodon each hyoidean artery has its origin from the ventral ends of the first efferent l:)ranchial arter}-. Passing along the dorsal surface of the liyoid arch it gives off the characteristic branch to tlie branchiostegal BLOOD-VASCULAR SYSTEM OF THE LORICATI II5 rays and then follows along in front of the interhyal, but when the preopercle is reached, instead of passing through a foramen formed by the symplectic, hyomandibular, and preopercular and anastomosing with the facialis-mandibularis artery to form the mandibular artery as in Ophiodon, it bifurcates; the ventral branch passes through the above mentioned foramen to become the uiandihular artery (tig. 35, Man.A.) ; while the dorsal branch passes along the inner surface of the preopercle, gives off a rather large opercular artery, and terminates in the pseudobranchial artery. Jugular Veins (tig. 35, J.V.). — The jugulars and their branches are practically the same as in Ophiodon. The first pair of efibranchial arteries (figs. 35 and 36 ; Epbr. A.(i)) unite in forming the dorsal aorta, and the second pair, the coeliaco-mesentric ; there is an opening into the aorta from the coeliaco-mesenteric artery, corresponding to the common chamber of Ophiodon, but the subclavians arise separately from the dorsal aorta, opposite the opening into the cceliaco-mesen- teric. Subclavian arteries. — Each subclavian (fig. 36, Sub. A.) after leaving the head kidney passes to the inner musculature of the corresponding pectoral fin. Here it separates into the subclavian artery proper, which is essentially the same as in Ophiodon, and a hypobranchial artery. This vessel (fig. 36; Hypobr.A.) passes ventrad a short distance, gives off a large branch, designated as \\iQ posterior ventral artery {^g. 36; Ven.A.(i^) which passes ventro-caudad, supplying the ventral fin musculature and terminates in the right and left ventral fin arteries. The main stem of the hypobranchial passes cephalad and ventrad, and together with the corresponding vessel from the opposite side anastomoses with the anterior ventral artery. On the left side the hypobranchial artery has no posterior ventral branch. The hypobranchial artery in Anoplopoma may not be homologous with the similar named vessel in Ophiodon, which is really a branch of the ventral artery and anastomoses with a branch of the subclavian. Only one subclavian venous trunk (fig. 36 ; Sub.V.(2^) was noticed. It arose from an external and an internal branch. Il6 ALLEN The outer subclavian vein penetrated the scapula with the cor- responding artery and joined the internal subclavian vein in formincr the common subclavian trunk, which terminates in its respective horn of the kidney. The vessel designated as the anterior ventral artery (fig. 36 ; Ven.A.) arises from the ventral union of the second right and left efferent branchial arteries ; principally, however, from the second left efferent branchial artery. After passing over the combined trunk of the third and fourth afferent branchial ves- sels it gives off the pharynx artery. This vessel (fig. 36 ; Phar.A.) supplies the phar3'nx region, and soon sends off the coronary artery {^g. 36; Cor. A), which passes along the dorsal side of the ventral aorta to the heart. In all other genera studied the pharynx artery arose directly from the second or the third efferent branchial arteries. The anterior ventral artery evi- dently corresponds to the ventral artery of the other species ; except that it extends only to the origin of the pelvic arch. In addition to giving off the phar3-nx artery it sends off branches to the sterno-hyoideus muscle and anastomoses with the 2 hypo- branchial arteries. It would be possible, however, in Anoplo- -ponia for blood in the anterior ventral artery to reach the ventral fins by passing through the right hypobranchial artery into the posterior ventral artery. By the separation of the right hypo- branchial from the subclavian we would have in the anterior ventral, right hypobranchial, and posterior ventral arteries an irregular shaped vessel corresponding somewhat to the ventral artery of the other genera. As in Scbastodes, there is in addition to the main inferior jugu- lar and left branch, a right inferior jugular, which drains the ventral branchial muscles from the right side and empties into the right precava. Civli'aco-incsenicn'e Artery. — This trunk {'C\\i,. 37 ; Cce.Mes.- A.) upon reaching the oesophagus separates into the coeliac and mesenteric arteries respectively. The mesenteric artery soon divides into intestinal artery^) and a short stem from which the rigiit and le_ft g'astric arteries have their source. The latter vessel (figs. 37 and 38; L.Gas.A.) makes a cephalic curve across the oesophagus and continues on the left side of the BLOOD- VASCULAR SYSTEM OF THE LORICATI II7 stomach to the apex; while the former (tig. 37; R.Gas.A.) crosses the corresponding vein and continues parallel with it along the right and dorsal side of the stomach to the apex. From the right gastric \\\^ posterior gaU-hladdcr artery is given off to supply the posterior two thirds of the bladder, and a small branch is also given off to a gland-like body marked G. Intestinal arterVd, (fig. 37 ; Int.A.^j^) crosses over the right portal and con- tinues caudad to the right of intestinal vein(,). Directly in front of the spleen this artery divides into a dorsal and a ventral ves- sel. The dorsal artery (fig. 37, Int.A.(|„,) passes to the right of the spleen, gives off the splenic artery (fig. 37 ; Spl.A.) to the spleen, and crossing the intestinal vessels^,) continues caudad along the posterior horn of the iliac loop ; giving off numerous branches to the anterior horn and the posterior end of the in- testine, and finally terminates on the dorsal side of the rectum. The ventral branch (fig. 37 ; Int.A.^,,,)) passes ventrad and to the left of the spleen. Opposite the spleen it sends off the ■posterior gastric artery (fig. 37 ; P. Gas, A.), which crosses the cajca behind the corresponding vein, and supplies the posterior or cardiac end of the stomach. The main ventral intestinal vessel continues along the lower side of the posterior end of the intestine and terminates on the ventral side of the rectum. Immediately after leaving the main trunk the celiac artery (fig- 37 ; Coe.A.) gives off the right hepatic artery (figs. 37 and 38; R.Hep.A.), which after crossing the cceliac and right portal sends off branches along the radicals of the right portal to the right lobe of the liver, and also gives off the anterior gall-bladder artery^ which supplies the anterior third of the bladder, and does not anastomose with the posterior gall- bladder artery. Passing beneath intestinal vesselS(i) the coeliac artery gives off a rather large leji hepatic artery (figs. 37 and 38; L.Hep.A.), which follows along in front of the left portal, giving off numerous branches to the left lobe of the liver, which penetrate the liver with the large radicals of the common por- tal ; while none of the branches of the left hepatic anastomose with similar branches of the right hepatic, several of them send up branches that supply the ventral portion of the stomach. Shortly after the branching off of the left hepatic from the Il8 ALLEN coeliac, intestinal artery^,) is given off to the right (fig. 37 ; Int. A. (2)); passing caudad to the right of the corresponding vein it crosses under the ventral branches of intestinal vesselS(i), the spleen, and the dorsal brandies of intestinal vessels, and continuing caudad between the anterior and posterior horns of the iliac loop, supplies both of them. The cceliac artery proper separates into the right and left ^yloi'ic ccuca arteries. The former (fig. 37 ; R.Ca^.A.) passes around the pylorus on p^'loric cajcum^T), and bifurcates into a dorsal and a ventral branch : the ventral branch gives off a large branch which crosses under this caecum, and continues caudad between cascum^j) and csecum(2), giving off branches to each. The left pyloric cceca artery (fig. 37 ; L.Ca^.A.) passes to the left of the pylorus be- tween c^ecum^^) and cjecum^-,), giving off branches to each. Portal System. — As in Schastodcs the 2 portals unite in forming a common portal, that breaks up into numerous radicals. The right portal (fig. 37 ; R.Por.V.) has its origin from the right gastric, and intestinal vein(,). Intestinal vein ^^^^ (fig. 37 ; Int. v., J,) arises from a dorsal and a ventral branch. The former (fig. 37 ; Int.V.(j^)) arises from the dorsal side of the rectum, and runs cephalad, parallel to the corresponding artery, but below it; receiving branches from the posterior end of the intestine and anterior horn of the iliac loop, it crosses intestinal vessels (2) and passes above and to the right of the spleen from which it receives the splenic vein {^\'-^. 37 ; Spl.V.). Directly in front of the spleen the dorsal intestinal vein receives the ventral intestinal branch (fig. 37 ; Int.V.^j,,)), which arises from the lower side of the rectum and passes forward along the ven- tral side of the corresponding artery. Curving around tlie ven- tral and left side of the spleen it receives two branches ; the first one, which is the posterior gastric vein (fig. 37 ; P.Gas.V.) arises from the cardiac end of the stomach, and runs along in front of the posterior gastric artery ; while the anterior vessel has its source from two branches, one coming from between pyloric ca'ca^,,,^^,, ,2)» '^^cl the other from ca'cum .,,. After receiving these branches the ventral intestinal branch crosses over intestinal vessels ^j)* '^"d in front of the spleen unites with BLOOD-VASCUI.AR SYSTEM OF THE LORICATl II9 the dorsal intestinal branch to form main intestinal vein ^^^^ which shortly joins the rig/it gastric vein (tig. 37 ; R.Gas.V.) to form the rig/it fortal. This trunk (fig. 37 ; R.Por.V.) passes under intestinal artery^^^, and when the right lobe of the liver is reached, sends off a branch to it, and anastomoses with the left portal to form the common portal. The branch to the right lobe of the liver receives the gall-bladder vein (fig. 37 ; G.Bl.V.), which drains the entire bladder, and receives a branch from a gland-like body marked G. The Icjt fortal vein (fig. 37 ; L.Por.V.) has its origin from intestinal vein^,) and two pyloric cteca veins. Intestinal vein ^^.^ (fig. 37 ; Int.V.(2)) arising from the iliac loop passes cephalad below the corresponding artery, and after crossing under the dorsal branch of intestinal vein^,), the spleen, and the ventral branch of intestinal vein^) it receives a vessel coming from the dorsal surface of pyloric caecum (3), designated as the right pyloric aecavein (fig. 37 ; R.Cte.V.), and later the left pyloric ccsca vein (fig. 37 ; L.C^e.V.), which arises from between the fourth and fifth pyloric cseca. The left portal thus formed curves around on the dorsal surface of the liver and anastomos- ing with the right portal forms the common portal trnnk (fig. 38 ; C.Por.V.), which gives off several terminal branches or radicals to the liver. Into this common portal is poured a rather large ventral gastric vein (fig. 38; V.Gas.V.), which may to some extent take the place of the absent left gastric vein found in Ophiodon. The dorsal aorta presents no peculiarities, except that there are a great number of spermatic arteries (fig. 37 ; Sper.A.), usually 9 or 10. Renal Portal System. — In the kidney there is a complete renal portal system. The caudal vein (fig. 37 ; Cau.V.) runs along the left dorsal surface of the kidney as the renal portal vein, giving off large afferent renal veins (fig. 37 ; A.Ren.V.) to each side ; while the much smaller efferent renal veins (fig. 37 ; E.Ren.V.) return the blood to the right cardinal. This trunk receives, directly, 9 or 10 spermatic veins (fig. 37 ; Sper.V.) from the reproductive organs. The intercostal veins (fig. 37 ; Intc.V.), however, do not empty directly into the cardinal, but reach it through the efferent renal veins. I20 ALLEN From the previous description it would seem that the vascular system of Anoplopotna exhibits many points of resemblance to the more generalized Teleosts. The external carotid, hyoidean, subclavian, hypobranchial, and coronary trunks appear to have a more primitive arrangement than is even shown in Scbastodcs. IX. GENERAL CONSIDERATIONS AND SUMMARY. Since it is almost impossible to determine whether certain variations in the blood vessels are primitive or secondary it is not the intention of this paper to draw any conclusions as re- gards the classification of this group on the basis of the circu- latory system, until after the anatomy of the other S3'stems has been worked up. Still it is thought, although perhaps not practicable, that the vascular system might be used in the class- ification of families and genera, but could not be used in the discrimination of species. In the genus Sebastodes a great number of species w^ere studied, both generalized and special- ized, but no more variation was noticed in different species than could be found among individuals of the same species. Several interestino: anastomoses were noticed in both the arterial and venous systems. In Ophiodon we have in the re- gion of the nasal sac a union of a branch of the internal carotid with one of the external carotid. The hyoidean artery anas- tomoses with the main stem of the external carotid to form the mandibular artery. A branch of the ventral artery joined one of the subclavian in the pectoral fin canal. The anterior spinal artery, a branch of the subclavian, united in the neural canal with the myelonal artery, a branch of the internal carotid. Two gall-bladder arteries unite on the surface of tlie bladder. Usually the posterior mesenteric artery communicates with in- testinal artery(,), and there are connecting arteries between the right pyloric ca3ca artery and intestinal artery(,,. In Scbastodcs the two anterior spermatic arteries unite with the posterior or spermatic artery projier. In Hexagrammos tlie two hepatic arteries anastomose. In Anoploponia the h3'oidean arteries anastomose with the pseudobranchial arteries, and the hypo- branchial arteries unite with the anterior ventral arter}'. Among the veins in Ophiodon there is an anastomosis under the nasal BLOOD-VASCULAR SYSTEM OF THE LORICATI 121 sac of a branch of the internal ju2- 16. General lateral view in the region of the left head kidney. To show the blood supply for the posterior part of the brain and the cord. (140) PKOC wash. ACAO. SCI., vol VI PLATE 1[ 13 PLATE III. Ophiodoti elongatus ; Blue cod. Hydrolagiis colliei; Chimsera (Fig. 26). Fig. 17. Represents the blood supply to and from the nasal sac, as seen from the right side. Anterior part of the eye shown in outline. 40 lb. Op/iiodoii, X 2. 18. Same as 17. Nasal sac in outline, to show the veins leaving the inner side of the sac. 19. Dissection of the right eye from the inside. The sclerotic coat and silver layer of the choroid are removed to show the large choroid sinus, the double rete mirabile or choroid gland, [and the iris vein, all of which run in the vascular layer of the choroid coat. 20 lb. Offtiodoii, natural size. 20. Same eye, but deeper dissection to show the choroid artery and its rete mirabile. 21. Frontal section through the retina and choroid coats, showing the choroid artery, the choroid sinus, and the retina artery in section. 20 lb. Op/iiodo7i, natural size. 22. Shows an inside view of the right eye. A sagittal incision was made nearly through an injected eye and the three coats were folded to the right. The entire course of the retina arterj' from its entrance with the optic nerve until it ends on the lens is distinctly shown. 15 lb. Ophiodon, X Vz ■ 23. General lateral view of the blood supply to and from the brain. 15 lb. Ophiodoii, natural size. 23^. Blood vessels to and from the auditory organs. 30 lb. Ophiodon ^ natural size. 24. General dorsal view of the vascular supply of the same brain as Fig. 23. Cranial nerves and anterior encephalic veins shown only on the right side. 25. Same brain as above from the ventral side. Cranial nerves not shown on the right side. , 26. General lateral view of the main branchial vessels of Hydrolagus colliei, Chimsera. Inserted to show the wide variation in the carotid arteries, y^yi- PHOC, kVASH ACAD, SCl., VOL. Vil. I 23 N. S.V.J •■ N. S.V.I P.EncU Mr.V. RLat A¥ yWR L>r. H. Car. 23a PLATE Hr Op"-. : ■ ' ,f^„ -rar PEncV. ACerA jj PCerVMV. ' j^^^ EncV RCerA CerA. " ■ EocA. A.CerV. Mr.A. T^ T3 j-y CCA Efil Y.m.R Obl.V, A.CerA. D.Chor.V. Cil.L A.Ret.M- V.Rel.M - Oph-V Cil B. OphA. 20 22 % Cii, N 25 V =^^vi;^ iAuJA TV •^p'^i PAull' l*VV. Opt A tncA n^^ ni^A PEncV ACerA RCerA Tib. Sac Vas AudV Inf. A 26 A.EncJ PEncA. I'Orbit Opt-'- \ "^ ...^ Orb A \ ^ ! ECarA D.Ao. Ep BrA, ^^^ "^ Cob Mes /s ( f\ ^'^''* F.Max -A \ li >f / P E.Br A. PLATE IV. Uexagrammos decagrainmus ; Sea trout (Figs. 27 and 28). Scorpcenichthys niarmoraUis ; Cabezon (Figs. 29 and 30). Sebastodes atiriculatus ; Rock cod (Figs. 31 and 34). Sebastodes Jlavidus ; Rock cod (Figs. 32 and 33). Fig. 27. Represents a general lateral view of the viscera of a 12 in. Hexagram- mos. The organs are greatly spread out, in order to better display their blood vessels. X^- 2S. Same specimen as above, showing the opposite or left side of the stomach. 29. General lateral view of the viscera of a 15 in. Scorpatnichihys. The organs are well spread out to show their blood supply and the liver is not figured. X ^• 30. Same specimen as above, showing the left or opposite side of the stomach, and including the liver and the inner surface of the left pectoral fin. Hepatic system shown in dotted lines. 31. Represents a general lateral view of the viscera of a 12 in. Sebastodes aiiriculaius. Body tilted to show the ventral surface of the kidney, and all the organs spread out so as to best reveal their blood vessels. Notice the spermatic vem emptying directly into the left precaval vein. 32. A portion of the viscera, showing the blood supply for the left side of the stomach (opposite side from Fig. 31), and the liver of a 10 in- Sebastodes Jlavidus. This species, though one of the most generalized of the genus, has a system of blood vessels identical with 5. auyicula- iiis, which is one of the most specialized. X %• 33. Shows the blood supply to the gall-bladder and to a gland-like body. Sebastodes flavidiis, XK- 34. Shows a variation in the vascular s^'stem to the gall-bladder. Sebas. todes atiriculatus, X z^- (144) PROC. WASH ACAO SCI.. VOL VII H Sc Se Se Fig. Proc. Wash. Acad. Sci., June, 1905. PLATE V. Anoplopoma Jimbria ; Black cod. Fig. 31;. Represents general lateral view of the principal trunks in the head re- . gion of Anoplopoma, X y^- 36. Shows general ventral view of the head region, including the pectoral and ventral fins of Anoplopoma. Ventral musculature and oesophagus removed to show the heart and union of the epibranchial arteries to form the dorsal aorta, coeliaco-mesenteric, and subclavian arteries. 37. View of the viscera of Anoplopoma from the left and dorsal side. X Yz- 38. A portion of the viscera of Anoplopoma from the left and ventral side. (146) PLATE V. PROC WASH ACAD SCI.. VOL. VH. R Porv LGasA vGasV E«JVlC«rA E,C«>A EBrA.! tf.Br.Ai. DA ONV \EncA; PLATE VI. Heart of OpJiiodon eloiigattis. Fig. 39 is from a photograph of the posterior half of a large OpJiiodojCs heart, looking inward and caudad. This heart had previously been injected with a gelatin mass and hardened in formalin, and the cut was made directly between the anterior and posterior auriculo-ventricular valves. 40. As above, is a photograph of the ventral side of a large Ophiodotis heart. A portion of the ventral wall of the ventricle had been removed to the depth of the central cavity to show the semi-lunar and auriculo- ventricular valves. X 2. Abbreviatio7is used. — Aur., Auricle. A.V.O., Auriculo-ventricular opening. A.V.V., Auriculo-ventricular valves. B.Art., Bulbus arteriosus. C.Art., Conus arteriosus. C.C.V., Central cavity of the ventricle. C.T., Connective tissue. L.F., Longitudinal folds or ridges. M.L., Muscular layer. S.A.O., Sinu-auric- ularopening. S. A. V. , Sinu-auricular valves. S.V., Semi-lunar valves. S.Ven., Sinus venosus. T.C.A., Trabecule carnse auricle. T.C.V., Trabecula; carnie ventricle. V.Ao., Ventral aorta. Ven., Ventricle. Text-fig. \. — Represents a transverse section through the auricle and ven- tricle of Ophiodon elongattis. This section was made through one of the auric- ulo-ventricular valves. Camera lucida. Leitz No. 2 obj. with lower lens removed. Textfig. 2. — Camera drawing of transverse section through the region of the conus arteriosus. Same obj. as above. Abbreviations used. — Aur., Auricle. A.V.V., Auriculo-ventricular valve. C.T., Connective tissue. E.M.F., Elastic muscle fibers. End., Endothelium. L.M., Longitudinal muscle fibers. S.V., Semi-lunar valves. T.^L, Transverse muscle fibers. Ven., Ventricle. (148) Proc. Wash. Acad. Sci., Vol. VII. Plate VI. S.Ven Ven. A.V.V. C. c.v. j^ S V. T. C.V. ; M"^ P i r w ■% ^ v./ \o. c. Art. i" '^ B.Art c \ y^n. /^ur. BLOOD-VASCULAR SYSTEM OF THE LORICATI I49 XIII. REFERENCE LETTERS AND ABBREVIATIONS USED IN THE FIGURES. The letter D or V prefixed to an abbreviation indicates dorsal or ventral ; R or L, right or left ; A or P, anterior or posterior ; Ex or In, external or internal. A series of similar named vessels is numbered from cephalad to caudad. A. A. Anterior ampulla. A.Aud.A. Anterior auditory artery. a to e. Terminal branches or radicals of the left portal. A.Bl. Air-bladder. A.Bl.A. Anterior air-bladder or retia mirabilia artery. A.Bl.V. Anterior air-bladder or retia mirabilia vein. A. Br. A. Afferent branchial arteries. Ab.V.S. Abductor muscle of ventral spine. A.Cer.A. Anterior cerebral artery. A.Cer.V. Anterior cerebral vein. Ad.Hym.' Adductor hyomandibularis. Ad.M.M. Adductor mandibulse muscles. Ad. Pal. A. Adductor palatine arch. M. adductor arcus palatini. A.Fil.A. Afferent filament arteries. A.G.Bl.A. Anterior gall-bladder artery. A.G.Bl.V. Anterior gall-bladder vein. A. Int. A. Anterior intestinal artery. A.Int.V. Anterior intestinal vein. A.Ps.Fil.A. Afferent pseudobranchial filament artery. A.R. Anal fin rays. A.Ren.V. Afferent or advehent renal veins. A.Ret.M. Arterial retia mirabilia of choroid gland. Aud.A. Auditory artery. Aud.C. Auditory capsule. Aud.V. Auditory vein. Aur. Auricle. B.Art. Bulbus arteriosus. Br. A. Branchial arches. Br.M.A. Dorsal branchial muscle arteries. Br.O.A. Branchiostegal arteries. Br.R, Branchiostegal rays. Cae. Pyloric caeca. Csefi) to (5) Five pyloric caeca of Anoplofoma. Camp.H. Campanula Halleri. Cau.A. Caudal artery. Cau.V. Caudal vein. CCA. 1 C''.C.A'. /- Cranial cavity arteries. Q".Q,".K". J C.Car.A. Common carotid artery. ccv. c.c.v. Cen. Centrum > Cranial cavity veins. 150 ALLEN Cer. Cerebellum. Cer.A. Cerebellum artery- Cer.H. Cerebral lobes or hemispheres. Chor. Choroid coat of the eye. Chor.A Choroid arteries. Chor.A.(i) Superior choroid artery. Chor.A. (2) Inferior choroid artery. Chor.S. Choroid sinus. Chor.V. Choroid veins. Cil.B. Ramus ciliaris breyis. Cil.L. Ramus ciliaris longus. Cil.N. Ciliary nerve. C.L.Sin. Caudal lymphatic sinus. Cce.A. Coeliac artery. Coe.Mes.A. Cceliaco-mesenteric artery. Con. Art. Conus arteriosus. Cor. A. Coronary artery. Cor.V. Coronary vein. C.P.V. Common portal vein. Sebastodes and Anoflopoma only. C.R. Caudal fin rays. Cran. Cranial wall. Q./V .' Connecting vein. OpJiiodon and ScorpanicJithys only. C.Ver. Caudal vertebra. D.Ao. Dorsal aorta. D.Br.R.M. Dorsal branchial retractor muscle. Retractor arc. branch dorsalis of Vetter. D. Chor.V. Dorsal choroid vein. Di.Op.M. Dilator opercular muscle. D.Lat.A. Dorsal lateral arteries. D.Lat.V. Dorsal lateral veins. D. & L.M.P.R. Depressor and levator muscles of the pectoral rays. D.L.V. Dorsal lymphatic vessel. D.M.A.R. Depressor muscle, anal ray. D.M.D.R. Depressor muscle, dorsal ray. D.O.M. Dorsal oblique muscles of the branchial arches (3). Obliqui dorsales of Vetter. D.R. Dorsal fin rays. D.S. Dorsal spines. E.A. External ampulla. E.Br. A. Efferent branchial arteries. E.Br.L. External branchial levator muscles (4). Levatores arch, branch extern i of Vetter. E.Car.A. External carotid artery. E.Fil.A. Efferent filament arteries. Enc.A. Encephalic artery. Enc.V. Encephalic vein. Epbr.A. Epibranchial arteries. Epi. Epiphysis. E.Ps.Fil.A. Efferent pseudobranchial filament arteries. BLOOD- VASCULAR SYSTEM OF THE LORICATI I5I E.Ren. A. Efferent renal or revehent renal veins. E.Sub.A. External subclavian artery. Eth. Ethmoid. Ex.J.V. External jugular vein. Ex.R.A. External rectus artery. Ex.R.M. External rectus muscle. Ex.R.V. External rectus vein. F.A. Facial artery. Fal.P. Falciform process. Fil.Net. Branchial filament network. F.Man. A. Facialis-mandihularis artery. F.Man.V. Facialis-mandibularis vein. F.Max. A. Facialis-maxillaris artery. F.Max.V. Facialis-maxillaris vein. G. Gland. G.B. Gall-bladder. Ghs.A. Geniohyoideus artery. Ghs.M. Geniohyoideus muscle. Ghs.V. Geniohyoideus vein. Gl.H. Glossohyal. H. Hypophysis. Hje.A. Hiemal arteries. Hae.L.V. Haemal lymphatic vessels. Hse.V. Haemal veins. Hep.S. Hepatic sinus. Hep.V. Hepatic vein. H.Kid. Head kidney. H.S. Haemal spine. H.S.C. Horizontal or external semicircular canal. Hyo.A. Hyoidean artery. Hyoid. Hyoid arch. Hyo.V. Hyoidean vein. Hyp. Hypural bone. Hypobr.A. Hypobranchial artery. Hys.A. Hyohyoideus inferior artery. Hys.M. Hyohyoideus inferior muscle. Hys.S.M. Hyohyoideus superior muscle. Hvs.V. Hyohyoideus inferior vein. I.Br.L. Internal branchial levator muscles (2). Levatores arcuum branchialium interni of Vetter. I. Car. A. Internal carotid artery. I.Ir.V. Inner iris vein. I.J.V. Inferior jugular vein. I.lob.V. Interlobular veins. Inf. A. Infundibular artery. Inf.L.. Hypoaria or inferior lobes. Inf.O.A. Inferior oblique muscle artery. Inf.O.M. Inferior oblique muscle. Inf.O.V. Inferior oblique muscle vein. 152 ALLEN Inf.R.M. Inferior rectus muscle. In.H. Interhyal. In.J.V. Internal jugular vein. In. Man. M. Intermandibularis muscle. Int. Intestine. Int.A.(i). Intestinal artery(i). Int.A.(io). Dorsal branch of intestinal artery(t). In Anoplopoma. Int.A.(ij). Ventral branch of intestinal arterjd). In Anoplopoma. Int. A. (2). Intestinal artery(2). Intc.A. Intercostal arteries. Intc.V. Intercostal veins. Int.R.A. Internal rectus artery. Int.R.M. Internal rectus muscle. Int.R.V. Internal rectus vein. Int.V.(i). Intestinal veina). Int. V. do). Dorsal branch of intestinal vein(ij. In Afioplopoma. Int.V.(ij). Ventral branch of intestinal vein(i). In Anoplopoma. Int.V.(2). Intestinal vein(2). Ir. Iris. Ir.A. Iris artery. Ir.V. Iris vein. Ir.V.(i). Ventral or minor iris vein. I. Sub. A. Internal subclavian artery. I.Sub.A.(i). Superficial branch of the internal subclavian artery. I. Sub. A. (2). Profundus branch of the internal subclavian aitery. J.L.O. Jugular lymphatic opening. J.V. Jugular vein. Kid. Kidney. L. Liver. Lat.A. Lateral arteries. Lat.V. Lateral veins. L.Cse.A. Left pyloric caeca artery. L.Cse.V. Left pyloric caeca vein. L.Car.V. Left cardinal vein. L.Cau.A. Left caudal artery. L.Cau.V. Left caudal vein. L.Gas.A. Left gastric artery. L.Gas.V. Left gastric vein. L.G.X. Left gastric ramus of the vagus. L.Hae.L.V. Longitudinal haemal lymphatic vessel. L.Hep.A. Left hepatic artery. L.IIep.A.(i). Posterior or minor left hepatic artery. L.IIep.V. Left hepatic vein. Lin. A. Lingual artery. Lin.V. Lingual vein. L.L.V. Lateral lymphatic vessel. L.M.A.R. Levator muscles of the anal rays. L.M.D.R. Levator muscles of the dorsal rays. L.Neu.L.V. Longitudinal neuial lymphatic vessel. BLOOD-VASCULAR SYSTEM OF THE LORICATI I53 L.Op.M. Levator opercular muscle. L.Pal.A. Levator palatine arch. Levator arcus palatini of Vetter. L. Pal. A. A. Levator of palatine arch artery. L. P. Gas. A. Left posterior gastric artery. L.P.Gas.V. Left posterior gastric vein. L.Por.V. Left portal vein. L.Sper.A. Left spermatic artery. In Sebastodcs. L.Sper.V. Left spermatic vein. In Sebastodes and Scorpcrnichthys. L.Ven.V. Left ventral vein. L.V.Fin.A. ■ Left ventral fin artery. L.V.Fin.V. Left ventral fin vein. Man. Mandible (Dentary, articular, and angular bones). Man. A. Mandibular artery. Man.V. Mandibular vein. Max. Maxilla. Max.A.(i). Anterior or maxillary artery. Max. A. (2). Posterior maxillary artery. Max.V. Maxillary vein. Me. A. Mesencephalic artery. Mes.A. Mesenteric artery. Me.V. Mesencephalic vein. M.Lat.A. Median lateral arteries. M.Lat.V. Median lateral veins. My. Myelon, myel, or spinal cord. My. A. Myelonal artery. My.V. Myelonal vein. N.Br. A. Nutrient branchial arteries. N.Br.V. Nutrient branchial veins. Neu.A. Neural arteries. Neu.L.V. Neural lymphatic vessels. Neu.V. Neural veins. N.Fil.A. Nutrient branchial filament artery. N.Fil.V. Nutrient branchial filament vein. N.S. Nasal sac. N.''S.'' Neural spines. N.S.A. Nasal sac arteries. N.S.V.(i). Anterior nasal sac vein. N.S.V.(2). Posterior nasal sac vein. Obi. Oblongata or medulla oblongata. Obl.V. Oblongata vein. Oc.Cl.V. Occipito-clavicularis muscle. O.D.M. Obliqui dorsales muscles. Oes. Oesophagus. Olf.L. Olfactory lobes or bulbs. O.N. A. Orbito-nasal artery. O.N.V. Orbito-nasal vein. Op. A. Opercular artery. Oph.A. Ophthalmic artery. Oph.V. Ophthalmic vein. 154 ALLEN Opt. A. Optic or retina arterj. Opt.L. Optic lobes. Opt.V. Optic or retina vein. Op.V. Opercular vein. Orb. A. Orbital arterj. In Hydrolagus. Ov. Ovaries. O.V.M. Obliqui ventrales muscles. P. A. Posterior ampulla. P.A.Bl.A. Posterior air-bladder arterj. P.A.Bl.V. Posterior air-bladder vein. Paras. Parasphenoid. P.Aud.A. Posterior auditorj arterj. P.Aud.V. Posterior auditorj vein. P.C.E.M. Pharjngo-clavicularis externus muscle. P.Cer.A. Posterior cerebral arterj. P.Cer.V. Posterior cerebral vein. P.C.I. M. Pharjngo-clavicularis internus muscle. P. E.Br. A. Posterior efferent branchial arteries. In Hydrolagtis. Pec.F. Pectoral fin. Pel. Pelvic arch. Pel. P. Ventral process of the pelvic arch. P.Enc.V. Posterior encephalic vein. P. Gas. A. Posterior gastric arterj. P.Gas.V. Posterior gastric vein. P.G.Bl.A. Posterior gall-bladder artery. P.G.Bl.V. Posterior gall-bladder vein. Phar.A. Pharynx arterj. Ph.H.M. Pharyngo-hjoideus muscle. P.Hjo.A. Posterior hjoidean arterj. Pig.L. Pigment lajer of the choroid coat. P.Mes.A. Posterior mesenteric arterj. P.Mes.V. Posterior mesenteric vein. P.P.Ad.M. Pectoral profundus adductor muscle. Prec.V. Precaval vein or Ductus Cuvieri. Pref. Prefrontal. Prem. Premaxilla. Preo. Preopercular. Pro. Prootic process. Ps.A. Pseudobranchial arterj. P.S.Ad.M. Pectoral superficialis adductor muscle. Pseu. Pseudobranchia. P&.Fil.Net. Pseudobranchial filament capillary network. Pj. Pjlorus. Pjl.A. Pjloric arterj. Pjl.V. Pjloric vein. R.Cie.A. Right pjloric caeca arterj. R.Cie.V. Right pyloric caeca vein. R.Car.V. Right cardinal vein. R.Cau.A. Riyht caudal arterv. BLOOD-VASCULAR SYSTEM OF THE LORICATI 1 55 R.Cau.V. Right caudal vein. Rec. Rectum. Rec.A. Rectus artery. Rec.V. Rectus vein. Ren. A. Renal arteries. Ren.P.V. Renal portal vein. Ret. Retina. Ret.F. Retina fissure. R.G. Gland-like body in retina fissure. R Gas. A. Right gastric artery. R.Gas.V. Right gastric vein. R.Hep.A. Right hepatic artery. R.Hep.V. Right hepatic vein. R.Hvo. Ramus hyoideus. R.Lat.X. Ramus lateralis vagi. R.Lat.A.V. Facialis portion of the ramus lateralis accessorius. R.Lat.A.X. Vagus portion of the ramus lateralis accessorius. R.Man. Ramus mandibularis VII. R.Man.V. Ramus mandibularis trigemini or ramus maxillaris inferior trigemini. R.Max.V. Ramus maxillaris trigemini or ramus maxillaris superior tri- gemini. R. P. Gas. A. Right posterior gastric artery. R.P.Gas.V. Right posterior gastric vein. R.Por.V. Right portal vein. R.Sper.A. Right spermatic artery. In Sebastodcs. R.Sper.V. Right spermatic vein. In Sebastodes and ScorpcejiicJithys. R.Ven.V. Right ventral vein. R.V.Fin.A. Right ventral fin artery. R.V.Fin.V. Right ventral fin vein. S. Suprarenal bodies. Sac.Vas. Saccus vasculosus. Scl. Sclerotic coat. Scl.A. Sclerotic artery. Scl.Ir.A. Sclerotic-iris artery. Scl.V. Sclerotic vein. SD.M. Superficial dorsal fin muscles. S.F. Scapula foramen. Sil.L. Silver layer of choroid coat. Sin.Ven. Sinus venosus. S.Lob.V. Sublobular veins. Sp.A. Spinal or myelon arteries. Sper.A. Spermatic arteries. Sper.V. Spermatic veins. Spl. Spleen. Spl.A. Splenic artery. Spl.V. Splenic vein. Sp.V. Spinal or myelon veins. Sr.A. Suprarenal artery. 156 ALLEN Sr.V. Suprarenal vein. St. Stomach. Ster.hy.M. Sternohjoideus muscle. Ster.A. Sternohyoideus arteries. Ster.V. Sternohyoideus veins. Sub. A. Subclavian artery. Sub.S. Subclavian sinus. Sub.V.(i). Internal subclavian vein. Sub.V.(2). External subclavian vein. Sub.V.(3). Minor external subclavian vein. In Ophiodoii. Sup.O.A. Superior oblique muscle artery. Sup.O.M. Superior oblique muscle. Sup.O.V. Superior oblique muscle vein. Sup.R.A. Superior rectus muscle artery. Sup.R.M. Superior rectus muscle. Sup.R.V. Superior rectus muscle vein. Tes. Testes. Thym. Thymus gland. Thyr. Thyroid gland. Thyr.A. Thyroid artery. Trap.M. Trapezius muscle. Tub. Tuber (cinereum). T.V. Transversus ventralis muscle. Ur. Ureters. Ur.Bl.A. Urinary bladder artery. (Ur.B.A., in Ofhiodon.^ Ur.Bl. Urinary bladder. Ur.Bl.V. Urinary bladder vein. (Ur.B.V., in Of//iodo)i.) Ur.S. Urostyle. Ut. Utriculus. V.Ao. Ventral aorta. Vas.L. Vascular layer of the choroid coat. V.Chor.V. Ventral choroid vein. Ven. Ventricle. Ven.A. Ventral artery. Ven.A.(i). Posterior ventral artery. In Anoplopoma. Ven.F. Ventral or pelvic fins. Ver. Vertebra. V.Gas.A. Ventral gastric arteries. V.Gas.V. Ventral gastric veins. V.Intc.A. Ventral intercostal arteries. V.Intc.V. Ventral intercostal veins. V.Lat.A. Ventral lateral arteries. V.Lat.V. Ventral lateral veins. V.L.V. Ventral lymphatic vessel. V.Myo. Ventral myotomes. Vo. Vomer. V.P.Ad.M. Ventral or pelvic profundus adductor muscle. "Adductor pro- fundus pelvis of McMurrich. V.Ret.M. Venous retia mirabilia of the choroid. BLOOD-VASCULAR SYSTEM OF THE LORICATI I57 V.S. Ventral spine. V.S.Ad.M. Ventral or pelvic superficialis adductor muscle. Adductor superficialis pelvis of McMurrich. X. Place for injecting the arteries. Y. Intestinal branch of posterior mesenteric vein. Z. Gastric branch of posterior mesenteric vein. I. Olfactory nerve. II. Optic nerve. III. Oculomotor nerve. IV. Pathetic or trochlear nerve. V and VII. Trigemino-facial complex. VI. Abducent nerve. VIII. Auditory nerve. IX. Glossopharyngeal nerve. X. Vagus or pneumogastric nerve. V(n. Truncus supra-orbitalis or ramus ophthalmicus superficialis V and ramus ophthalmicus superficialis VII. V,2,. Truncus infra-orbitalis or buccalis-maxillo-mandibularis. V(3). Truncus hyomandibularis or hyoideo-mandibularis facialis. V.VII.R. Trigemino-facialis roots. V.Scl. Supra-orbital ramus to sclerotic coat. X.D. Dorsal root of the vagus. X.V. Ventral root of the vagus. PROCEEDINGS WASHINGTON ACADEMY OF SCIENCES Vol. VII, pp. 157-1S6. [Plates vii-xi.] June 30, 190^ THE GYMNOTID^. By Carl H. Eigenmann and David Perkins Ward. CONTENTS. lutroduction 159 Key to the Genera of Gjmnotidce 160 Genera and Species 161 Table showing known Geographical Distribution 179 Explanation of Plates iSo The Gymnotidae are a family of fishes entirely confined to the fresh waters of tropical America. At least 4 species [Ster- narchus brasiliensis, Rhamj^hichthys marmoratus, Eigenmannia virescens and Giton fasciattis) range as far south as the Rio de la Plata, the second having been taken at Rio Grande do Sul but not yet in the La Plata. The last three species range from the Orinoco south through the Amazon basin and the Paraguay basin ; no species is represented in the coast-wise streams be- tween Bahia and Rio Grande do Sul ; and but one, Giton fas- ciattis, reaches Bahia. Four, Sternarc/ncs brasiliensis, Eigen- mannia virescens, Giton fas ciatus and Gymnotus carapus have been found in the Rio San Francisco. But 2 species have representatives on the Pacific slope, Eigenmannia hiimboldti, which is found in the Magdalena basin and in the Mamoni, a stream emptying into the Pacific in Panama, and Gyuinotiis ceqiiilabiatiLS , which is found in the Magdalena basin and about Guayaquil. North of Panama only a single species, Giton fasciatits, has been found. It has been recorded by Giinther from the Rio Motagua. The same species is also found in the island of Trinidad and the islands of Grenada. Proc. Wash. Acad. Sci., June, 1905. (159) l6o EIGENMANN AND WARD Several species are found in the Paraguay and Amazon rivers which have not been reported from as far south as the La Plata. These are Hypopoinus brcvii'ostris from the Cauca to Para and Paraguay, Stcrnarchiis alhifrons and Gymnotus carajyiis from the Orinoco through the entire course of the Amazons from Peru to Para and to Paragua}'', and Rhamphichthys 7'cinhardti which is not found north of the Amazons. The place where more collections have been made than else- where and which must serve as an index of the abundance of the South American fish fauna is Manaos, or Barra do Rio Negro. At this place or in its neighborhood 12 of the 29 species have been taken; 21 species have been taken in the Amazons but not more than 14 in any one of its 3 sections. The ac- companying geographical table will give an idea of the abun- dance of local faunas or the thoroughness with which collecting has been done. Fifty species have been described, of which 29 seem to be valid. KEY TO THE GENERA OF GVM.VOTID.4i:. a. Caudal fin present ; eye without free orbital margin ; a large fon- tanel ( Sternarchincc. ) b. Snout not producec], the eye nearer tip of snout than to gill- opening. c. Both jaws with teeth, tliose of the lower jaw in 2 series, those of the upper in 3 or more series. d. Gape long, the angle of the mouth but little if any in front of eye; snout long Sternai-chus^ i« dd. Gape short, the angle of the mouth below the anterior or posterior nostrils; snout short Sternai-cheUa^ 2. cc. Upper jaw without teeth, those of the lower jaw in a single series; snout very short Sternaj'c/iogiton^ 2>' hh. Snout produced, the eye nearer the gill-opening than to tip of snout ; anal long. e. Snout straight, the gape moderate SteruarchorhainpJiits^ 4. ce. Snout strongly decurved ; mouth minute, the gape about twice length of eye Sicruarc/iorZ/ync/ms^ 5. aa. No caudual fin, the tail ending in a point. f. A large fontanel ; vent below the head. ' If Peter's description of S(crna>x/ius sacJtsi is correct and sachsi does not contain teeth in either jaw, it should stand as the type of a new genus. THE GYMNOTID^ l6l o. Snout produced into a long tube; no teeth; vent below or in advance of eyes ; anal fin beginning at throat; eye nearer gill-opening than end of snout Rhamphichthys^ 6. gg. Snout not produced into a long tube. //. No teeth; vent behind eyes; anal beginning below pec- toral ; eye nearer tip of snout than gill-opening, minute. /. jMental region without adipose filament Ilypopoimis^ 7. ii. Mental region with a filament of adipose tissue in a groove along each side Stcatogeiiys^ S. Jih. Teeth present in both jaws. j. Eye without a free orbital margin ; jaws equal or the upper the longer; teeth feeble, in a patch or band; anal beginning below or in front of pectoral ; snout more or less compressed, conical ; eye large. Eigen7)ia7i7tia^ 9. jj. Eye small, with a free orbital margin; teeth feeble, in bands ; jaws equal or the upper the longer ; gill-open- ing small ; anal beginning below pectoral or slightly in front of it; vent in fi'ont of gill-opening; snout blunt, conical Gymnottts^ 10. ^. No fontanel ; maxillary very small ; lower jaw projecting ; teeth rather strong, in a single series in each jaw ; anal begin- ning behind pectoral ; vent below gill-opening; gill-opening comparatively large; head depressed in front; eye small. Giio7z, 1 1 . I. Sternarchus Bloch & Schneider. (Figs. 1-3.) Stcrnarchiis Bloch & Schneider, 497, tab. 94. (Type: Gym- notus albifrons L.) Sternarcluis Cuvier, Regne Animal, II, 237, 1817 {albifrons). Apteronotus Lacepede, II, 208 {j)assan = albifrons). Geographical distribution of the species : Amazons ; Rio San Francisco, Paraguay and Parana. a. Scales small, a maximum of 16 rows between lateral line and middle line of back.^ b. A maximum of 1 1 to 16 scales between lateral line and middle of back; angle of mouth in front of eye; snout 3.35 in head; depth of snout just in front of eye less than length of snout; depth of head more than 1.5 in its length brasiliensis., i. ' Not examined in ^S. bonapartii. l62 EIGENMANN AND WARD bb. A maximum of 1 1 to 13 scales between lateral line and middle line of back ; angle of mouth just below or a trifle in front of eye ; snout about 2.5 in head ; depth of snout just in front of eye equaling or exceeding length of snout ; depth of head about 1.35 in its length albifro?is, 2. bbb. Angle of mouth behind e3-e ; vent in front of eye; A. 165. ( Castelnau ) bonapartii^ 3 . aa. Scales large, a maximum of 6 scales between lateral line and middle line of back macrolepis^ 4. I. STERN ARCHUS BRASILIENSIS Reinhardt. Sternarchus brasiliensis Reinhardt, Vidensk. Meddel. Naturh. Foren. Kjobenh., 1852, or Wiegm. Arch. 1854, 182; Giin- ther, Cat., VIII, 3, 1870 (Rio das Velhas) Lutken, Velhas Flodens Fiske, 247 and XIX, 1875 (Rio das Velhas) ; Stein- dachner, Flussf. Siidam., Ill, 14, 1881 (Rio das Velhas) ; Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., XIV, 189T, 61 (Rio das Velhas). SternarcJuLS alb(frons, Eigenmann & Norris, Revista Museu Paulista, IV, 349, 1900 (Piracicaba) ; not of Linnaeus. Habitat : Southeastern Brazil but not in its coastwise streams. 2. STERNARCHUS ALBIFRONS (Linnceus). Gyninotus alhifrons Linnaeus, Syst. Nat., ed. XII, i, 428, 1766 ; Pallas, Spic. Zool., VII, 36, tab. 6, fig. i, 1769; Bonnaterre, Tabl. encycl. des trois regnes natura, Poiss., 37, pi. 24; fig. 82, m. 3, 1788. Sternarchus albifrons, Bloch & Schneider, 497, tab. 94 ; Castel- nau, Anim. Amer. Slid, Poiss., 91, pi. 45, fig. i, 1855; Kaup. Apodes, 126; Steindachner, Sb. Akad. Wiss. Wien, LVIII, 1868, 249 (Cuyaba). Giinther, Cat., VIII, 2, 1870 (Para; Santarem) ; Peters, Mb. Akad. Wiss. Berl., 1877, 473 (Apure) ; Cope, Proc. Am. Philos. Soc. 1878, (Peru- vian Amazon); Boulenger, Proc. Zool. Soc. 18S7, 282, (Canelos) ; Steindachner, Flussf. Siidam., Ill, 13, pi. 5, fig- 6, 1881 (Manacapuru ; Teff e ; Obidos) ; Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., XIV, 1891,61 ; Perugia, Ann. Mus. Civics Stor. Nat. Genova, ser. 2, vol. 4, 55, 1891 (Asuncion); Boulenger, Trans. Zool. Soc, XIV, 1896 THE GYMNOTID^E 163 37 (Descalvados) ; Boulenger, Boll. Torino, XIII, 1898 (Rio Zamora, Eqiiador) ; Eigenmann & Kennedy, Proc. Acad. Nat. Sci. Phila. 1903, 30 (Arroyo Trementina). A^tei'onotus fassan Lacepede, Hist. Nat. Poiss., II, 209, pi. 6, fig. 3, 1800. Sternarchus laccpcdu Castelnau, Anim. Amer. Sud, Poiss., 93, pi. 45, fig. 3, 1855, Surinam. Sternarchus maxiniilliani Castelnau, 93, pi. 45, fig. 4, 1855, Urubamba. Habitat : Orinoco, Amazons and Paraguay. 3. STERNARCHUS BONAPARTII Castelnau. Sternarchus bonapartii Castelnau, Anim. Amer. Sud, Poiss., 92, pi. 45, fig. 2, 1855, Amazon; Kaup, Apod., 126, 1856; Giinther, Cat., VIII, 3, 1870; Cope, Proc. Am. Philos. Soc. 1878, 682 (Peruvian Amazon) ; Steindachner, Flussf. Siidam., II, 42, 1881 (Manacapuru) ; Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., XIV, 1891, 62. Habitat: Amazons. 4. STERNARCHUS MACROLEPIS Steindachner. Sternarchus macrolepts Steindachner, Flussf. Siidam., Ill, 14, pi. V, fig. 7, 1 88 1, near Barra do Rio Negro and Lake Man- acapuru ; Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., XIV, 1891, 62; Boulenger, Trans. Zool. Soc, XIV, 427, 1898 (Riojurua). Habitat : Amazon near mouth of Rio Negro and Jurua. 2. Sternarchella Eigenmann, new genus. (Fig. 4.) Type : Sternarchus schotti Steindachner. A glance at the figures of the species of Sternarchus and the type of this genus will show conclusively that schotti is not con- generic with Sternarchus alhifrons. The snout is much shorter and the mouth is very much smaller. Geographical distribution of the species : Barra do Rio Negro to Peru. a. Gape moderate, angle of mouth below posterior nostril ; A. 163; teeth of premaxillary and mandible in 2 series ; opercle pointed ; 164 EIGENMANN AND WARD snout 3.4 in head ; depth of snout in front of eye mucli less tlian its length; depth of head 1.4 in its length. (Steindachner) schotti^ 5. aa. Gape short, angle of mouth below anterior nostril ; A. 171 ; only 9 transverse scales below dorsal ; lower jaw large, pi^ojecting beyond upper both anteriorly and laterally; eye much nearer tip of snout than gill-opening; depth equaling length of head, 8.5 in the length. (Cope) balcBiiops^ 6. 5. STERNARCHELLA SCHOTTI (Steindachner). SternarcJiiis schotti Steindachner, Die Gymnotidce, 4, pi. I, figs. I and 2, 186S, Barra do Rio Negro ; Giinther, Ca:t., VIII, 3, 1870; Cope, Proc. Am. Philos. Soc. 1878, 682 (Peruvian Amazon); Steindachner, Flussf. Sudam., II, 42, pi. 2, fig. 2, 1881 (Manacapuru) ; Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., XIV, 1891, 62. Habitat : Amazons, from the Barra do Rio Negro to Peru. 6. STERNARCHELLA BAL^NOPS (Cope). Sternarchiis balcenops Cope, Proc. Am. Philos. Soc. 1878, 682 Peruvian Amazon ; Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., XIV, 1891, 62. Habitat: Peruvian Amazon. 3. Sternarchogiton Eigenmann, new genus. (Fig. 5.) Type : Sternarc/uis iiatte^'ei'i Steindachner. Steindachner in his original description recognized that S. nattereri represents a distinct group of Sternarchoid fishes. It is sufficiently distinguished by the absence of teeth in the upper jaw. {^Sternarchiis and yscvcou, neighbor.) Geographical distribution of the species : Orinoco to Barra do Rio Negro. a. Lower jaw with a single scries of teeth; head 12 ; depth S; snout 3.5 in the head; A. 197; anus below eye; snout very short and convex. (Steindachner) iiattcrei-i^ 7. aa. Lower jaw without teeth ; A. 16S; head 10.5; depth 13.3; snout pointed; eye 3 in snout; lower jaw projecting; anterior nares in middle of length of snout, the posterior close to eye. (Peters) sac/isi^ S. THE GVMNOTID^ l6$ 7. STERNARCHOGITON NATTERERI (Steindachner). Sternarchus «ci'//^rf;"/ Steindachner, Die Gymnotidiu, 3, pi. II, fig. I, 188S, Barrado RioNegro ; Giinther, Cat., VIII, 3, 1870; Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., XIV, 1891, 62 ; Boulenger, Trans. Zool. Soc, XIV, 427, 1898 (Rio Jurua) Habitat: Barra do Rio Negro and Jurua. 8. STERNARCHOGITON SACHSI (Peters). SteniarcJms sachsi Peters, Mb. Akad. Wiss. Berl. 1877, 473, Apure ; Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., XIV, 189T, 62. Habitat : Orinoco. 4. Sternarchorhamphus Eigenmann, new -genus. (Figs. 6 and 7.) Type : Sternarchtis imilleri Steindachner. This genus is intermediate between Sternarchus and Ster- narchorhynchus, having the long snout of the latter and the mouth in size approaching the former. Geographical distribution of the species : Amazon at Para and in Peru. a. Snout nearly or quite straight, the gape wide, more than half length of snout ; eye midway between pectoral and tip of snout ; mandible with a series of fine teeth on each side; depth 2.5 in head; A. 202. (Giinther) 7?iacrosto??ius^g. aa. Snout nearly straight, the gape moderate, \ length of snout; depth of head 1.6 in its length ; 3 rows of slender teeth in lower jaw, 2 rows of smaller teeth in upper jaw; eye minute; depth less than length of head, 11 to 12 in total length. (Stein- dachner) vmlleri^ 10. aaa. Snout straight ; gape very small, not more than -^-^ of the length of the snout; depth of head about i of its length ; eye ex- tremely minute, about midway between pectoral and tip of snout ; several rows of minute teeth ; depth of body \ the length of the head ; a very strongly developed adipose fin along entire length ; vent under chin. A. 220, originating a little in advance of gill-opening; lat. line S5. (Boulenger) tainandtia^ 1 1. 1 66 EIGENMANN AND WARD 9. STERNARCHORHAMPUS MACROSTOMUS (Giinther). Siernarchtis macrostoimis Giinther, Cat., VIII, 4, 1870, Xeberos. RhanipJiosternarcJnis macrostomus^ Cope, Proc. Am. Philos. Soc. 1878, 682 (Peruvian Amazon). Sternarchorhynchus macrostomns, Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., XIV, 1891, 62. Habitat : Peruvian Amazon. 10. STERNARCHORHAMPHUS MULLERI (Steindachner). Sternarchiis [Rhamphosternarchus') mitlleri Steindachner, Flussf. Siidam., Ill, 15, pi. V, fig. 4, 1881, Para. Sternarchorhynchus mitlleri, Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., XIV, 1891, 62. Habitat: Para. II. STERNARCHORHAMPHUS TAMANDUA (Boulenger). Ster?iarchus tamandua Boulenger, Trans. Zool. Soc, XIV, 427, plate XLII, 1898, Rio Jurua, tributar}^ of the Amazon. Habitat : Rio Jurua. This species may represent a genus distinct from Stcr- narchorhamphiis as here understood. 5. Sternarchorhynchus Castelanu. (Figs. 9 and 10). StcrnarchorhyncJuis Castelnau, 1856. Type : Stcrnarcho- rhyncJms inulleri Castelnau = oxyrhynchus. Gill, Proc. Ac. Nat. Sci. Phila. 1864, 152. Rhamphosternarchus Giinther, Cat., VIII, 4, 1S70 {oxy- rhynchus). Rhamfhosicrnarchus Giinther is synonymous with Sternarcho- rhynchus Castelnau. It includes the species with a caudal and long tubular snout and minute mouth. Geographical distribution of the species : Marabitanos, Guiana and upper Amazon. a. Anal with more tlian 200 rays. h. Anal 210 to 226; mouth oblique; depth 1.6 to 1.75 in head. mormyrtis, 12. THE GYMNOTID^ 167 bb. Anal 205 to 215; mouth terminal; depth 3 in head. oxyrJiynch ns^ 13. aa. Anal 1S5 to 18S; snout much bent downward, its width at its middle 8 in its length; distance between eye and pectoral 1.5 in snout; depth 1.6 in head. (Boulengcr) curvirostris^ 14. 12. STERNARCHORHYNCHUS MORMYRUS (Steindachner). Sto-narcJms mo^-myriis Steindachner, Die Gymnotidoe, 5, pi. I, fig. 3, Marabitanos ; Giinther, Cat., VIII, 4, 1870 (Peruvian Amazon); Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., XIV, 1891, 62. Habitat: Marabitanos; Peruvian Amazon. 13. STERNARCHORHYNCHUS OXYRHYNCHUS (Miiller «fe Troschel). Stej'narchus oxyrhynchtis Miiller & Troschel, Hor^e Ichthyol., Ill, 16, pi. II, figs. I and 2, 1849, Essequibo ; Kaup, Apod., 127; Giinther, Cat., VIII, 4, 1870 (British Guiana); Boulenger, Trans. Zool. Soc, XIV, 427, 1898 (Rio Jurua). Sternai'chof'kync/ms oxyrhync/ms, Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., XIV, 1891, 62. Sternarchorhynchits imillc7'i, Castelnau, Anim. Amer. Sud. Poiss., 1855. Habitat: Guiana and Rio Jurua. 14. STERNARCHORHYNCHUS CURVIROSTRIS (Boulenger). St€?'7iarchus {Rhain^hostcrnarchus) ctirvirostris Boulenger, Proc. Zool. Soc. 1887, 282, pi. XXIV, Canelos. SternarchorhyncJms curvirostris, Eigenmann &, Eigenmann, Proc. U. S. Nat. Mus., XIV, 1881, 62. Habitat: Canelos. 6. Rhampbicbthys Miiller & Troschel. (Fig. 12.) Rhamfhichthys Miiller & Troschel, Hor^e Ichthyol., Ill, 15, 1849. (T'ype • Gymnotiis rosti'atus L.) 1 68 EIGENMANN AND WARD Geographical distribution of the species : Orinoco and Giiianas south to Rio de la Plata. ^ a. Eye equidistant from tips of snout and pectoral; distance of center of eye from gill-opening 2 in length of snout; eye 13 to 19 in head; anus in front of eye; A. 390 to 515 ; depth about 1.2 in head; brownish, variously spotted and banded. rostrattis^ 15. aa. Eye nearly equidistant from tip of snout and gill-opening; dis- tance of center of eye from tip of opercle i to 1.2S in snout. inarmorattis^ 16. aaa. Distance of eye from tip of opercle 1.5 in length of snout. i'einha7'dtii^ 17. 15. RHAMPHICHTHYS ROSTRATUS (Linnaeus). Seba, Thesaur, II, tab. 69, fig. 3, and III, 99, tab. 32, fig. 5. Gyninottis Gronow, Mus. Ichthyol., no. 73, 1754; Gronow, Zoophyl., no. 167. Gymnotus rostratiis Linnaeus, Syst. Nat., ed. XII, i, 428, 1766; Gronow, Syst., ed. Gray, 22, 1854. Cai'aftis rostratiis, Cuvier, Regne Animal, II, 237, 1817. Rhamphichthys roslraUis^ Miiller & Troschel, Horae Ichthyol., Ill, 15, 1849 (Guiana); Giinther, Cat., VIII, 5, 1870 (Suri- nam ; Brit. Guiana) ; Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., XIV, 1891, 62. Gymnotus longirostrattis Lacepede, Hist. Nat. Poiss., II, 178, 1800. Rhaniphichthys schomhurgkii Y^dM\^, Apod., 135, 10, 1856; Steindachner, Die Gymnotida?, 10, 1868, Rio Negro. Rhamphichthys sdineidcri Kaup, Apod., 136, fig. 11, 1856, Cayenne. Habitat : Guianas to Amazon. 16. RHAMPHICHTHYS MARMORATUS Castelnau. Rhamphichthys ma7'inoratus Castelnau, Anim. Amer. Sud, Poiss., 86, pi. 46, fig. 2, 1855, Uraguay ; Kaup, Apod., 132, fig- 7> 1856, Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., XIV, 1891, 62 ; Eigenmann, Ann. N. Y. Ac. Sci., VII, 1894, 625 (Itaituba). ' It seems quite probable that the " species " are simply different forms of a single variable species. THE GYMNOTID^ 169 Rhamphichthys fantherinus Castelnau, Anim. Amer. Sud, Poiss., 86, pi. 46, lig. 3, 1855, Lake near the Acayale ; Kaup, Apod., 131, fig. 6, 1856; Giinther, Cat., VII, 5, 1870; Peters, Mb. Akad. Wiss. Berl. 1877, 473 (Apure) ; Cope, Proc. Am. Philos. Soc. 1878, 682 (Peruvian Amazon) ; Stein- dachner, Fisch-f. Cauca and Guayaquil, 38, 1880 (Manaca- puru ; Matto Grosso ; Surinam ; Uraguay ; La Plata ; Para ; Obidos ; Xingu ; Rio Negro ; Ucayale). Perugia, Ann. Mus. Civico Stor. Nat. Genova, ser. 2, vol. X, 55, 1891 (Asuncion and Rio Maciel at Buenos Aires). Rhamphichthys Uneatiis Castelnau, Anim. Amer. Sud, Poiss., 87, pi. 47, fig. I, 1855, Tributary of Ucayale ; Kaup, Apod., 130, fig. 5, 1856. Gyinnotus rostratiis, Steindachner, die Gymnotidse, 8, 1868, in part (Matto Grosso ; Surinam) ; (not of Linnaeus). Habitat : Orinoco and Guianas south to Rio de la Plata. 17. RHAMPHICHTHYS REINHARDTII Kaup. Gymnotus rostratus, Bloch & Schneider, 522, tab. 106, 1801 ; not of Linnasus. Gyinnotus rostratits, Steindachner, Die Gymnotidje, 8, 1868 (Rio Negro) ; in part. Rhainphickthys reinhai'dtii Kaup, Apod., 132, fig. 8, 1856; Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., XIV, 1891, 62. Rhamfhichthys blochiiY^2L\v^, Apod., 133, fig. 9, 1856 ; Giinther, Cat., VIII, 5, i860 (Para); Steindachner, Fisch-f. Cauca and Guayaquil, 38, 1880 (Rio Negro; Manacapuru ; Para); Boulenger, Trans. Zool. Soc, XIV, 1896, 38 (Paraguay); Boulenger, Trans. Zool. Soc, XIV, 428, 1898 (Rio Jurua). Habitat : Guinas south to Paraguay. 7. Hypopomus Gill. (Fig. 13.) Hyfofonms Gill, Proc Ac. Nat. Sci. Phila. 1864, 152. Type : Rhamphichihys inulleri Kaup. Brachyrhamphichthys Giinther, Cat., VIII, 6 {aj'tcdti). Geographical distribution of the species : Cauca and Guianas south to Paraguay. 170 EIGENMANN AND WARD a. Snout less than 3 in head; spotted artedl^* iS. aa. Snout 3 or more in head ; sides with cross-bands. b. Head slender, compressed, conic: upper profile straight ; length of head equaling depth; eye about 2 in snout; A. 160 to 260. b)'evlrosti-is^ 19. 18. HYPOPOMUS ARTEDI (Kaup). Seba, III, tab. 32, fig. 2. Rhamphichthys artedlYs.?i\x^^^ K.^0^.^ 128, 1856, Mona ; Giinther, Cat., VIII, 6, 1870. Brachyrhamphichthys artedi\ Eigenmann & Eigenmann, Proc. U. S. Nat Mus., XIV, 1891, 62. Rhamphichthys miillcri Kaup, Apod., 129, 1856, French Gui- ana; Giinther, Cat., VIII, 6, 1870. Hypopomiis mulleri^ Gill, Proc. Ac. Nat. Sci. Phila. 1864, 152. Brachyrhamphichthys miiUeri^ Eigenmann & Eigenmann, Proc. U. S. Nat Mus., XIV, 1891, 62. Habitat : French Guiana. 19. HYPOPOMUS BREVIROSTRIS (Steindachner). Rhamphichthys brevirosti'is Steindachner, Die Gymnotidce, 6, pi. II, fig. 2; 1868, Guapore; Giinther, Cat., VIII, 6, 1S70; Steindachner, Fisch-f. Cauca and Guayaquil, 37, 1880 (San- tarem ; Cauca, Rio Guapore), Perugia, Ann. Mus. Civico Storia Nat. Genova, ser. 2, vol. X, 56, 1891 (Central Chaco) ; Boulenger, Trans. Zool. Soc, XIV, 1896,38 (Descalvados). Brachyrhaniphichthys hrevirostris^ Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., XIV, 1891, 62; Eigenmann, Ann. N. Y. Ac. Sci., VII, 1894, 625 (Lower Amazon and Itaituba on the Tocantins). Hypopomiis hrevirostris^ Eigenmann & Kennedy, Proc. Ac. Nat. Sci. Phila. 1903, 530 (Campo Grande; Arroyo Cha- galalina). Habitat : Cauca, Amazon and tributaries, Paraguay. * Tlie nominal species artedi \\x\<\ nitillcri a.rt distinguished as follows : tYellowish brown, marked with darker; fins without markings artedi. tt Upper side of head and back uniform black; lower part of sides of head and body with numerous spots; fins black, with brown ravs . . .muUcri. THE GWMNOTID^ I7I 8. Steatogenes Boulenger. (Fig. ii.) Stcatogcnes Boulenger, Trans. Zool. Soc. London, XIV, 1898, 428. Type : Rhamfhichthys cicgans Steindachner. a. Head chubby, upper profile convex; head 1.5 in the depth. A. 165 to 176 (Steindachner) elegans^ 20. 20. STEATOGENES ELEGANS (Steindachner). Rham^hichthys (JBrachyrhamfhichthys) clegans Steindachner, Fisch-f. Cauca and Guayaquil, 37, 1880, Barra do Rio Negro. Brachyrhamfhichthys clegans, Eigenmann & Eigenmann, Proc. U. S. Nat. Mus.,^XIV, 1891, 62. Stcatogenys clegans, Boulenger, Trans. Zool. Soc, XIV, 428, 1898 (Rio Jurua). Rhamphichthys [Brachyrha^nphichthys^ 7nirabilis Steindachner, /. c., pi. IX, figs. I and la. Habitat : Barra do Rio Negro. 9. Eigenmannia Jordan & Evermann. (Figs. 14 and 16.) Stcrnopygus Miiller & Troschel, Horce Ichthyol., Ill, 13 (spe- cies). Cryptop Eigenmann, Ann. N. Y. Ac. Sci.,VII, 626 {himi- boldtti) ; preoccupied. Eigenmannia Jordan «&; Evermann, Fishes North and Mid. Amer., I, 341, 1896 (substituted for Cryptops). Type : Sternofygiis Jmmboldtii Steindachner. Geographical distribution of the species : On the eastern slope from Magdalena to La Plata, Pacific Slope of Panama. a. " Maxillary shorter than the diameter of eye; eye without free lid, a little longer than snout or interocular space; mouth very narrow; upper jaw overlapping lower ; upper profile of head descending in a curve ; vent a little behind vertical of posterior border of eye; pectoral fin as long as head minus snout; A. 175, originating below middle of pectoral ; depth of body greater than length of head, 7.5 in length to end of anal ; tail produced be- yond anal in a very long appendage terminating filiform and measuring half total length without head ; scales very small. Uniform pale brownish; anal fin white." (Boulenger.) macrops, 2 r . aa. Maxillary about equal to orbit, the mouth small. 172 EIGENMANN AND WARD b. Ventral profile much more strongly convex than dorsal; head strongly compressed, triangular in profile ; upper profile of head nearly straight, a slight depression over eyes ; eye nearly 2 in snout; snout 3 to 3.25 in head; interorbital 3.25 to 3.7; width of head 2 to 2.25 Jmmboldtii^ 22. bb. Dorsal and ventral profiles equally convex; head less com- pressed ; upper profile of head straight ; eye nearly 2 in snout ; snout 3 in head; interorbital about 3 ; width of head 1.75 to 2 in its length virescens^ 23. aa. Maxillary about twice width of orbit. c. Eye 2 in snout ; jaws equal ; anal beginning below posterior third of pectoral ; a large blackish spot at origin of lateral line ; A. 212 axillaris^. 24. cc. Eye 2.5 in snout; lower jaw longer than upper; anal beginning below^ origin of pectoral ; color uniform ; A. 230. troschelii^ 25. 21. EIGENMANNIA MACROPS (Boulenger). Sternopygus 7jiacrops Boulenger, Ann. Mag. Nat. Hist. (6), XX, 305, Polaro River, British Guiana. 22. EIGENMANNIA HUMBOLDTII (Steindachner). Sternopygus humboldtii Steindachner, Fisch-f. Magd. Str. 55, pi. XIV, 1878, Magdalena ; id. Flussf. Siidam., i, 21, 1879 (Mamoni R. at Chepo) ; id. Fisch-fauna Cauca and Guayaquil, 36, 1880 (Cauca) ; Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., XIV, 1891, 62 ; Steindachner, Denk. Akad. Wiss.Wien, LXXII, 147, 1902 (Baranquilla on Rio Magdalena). Cry^tofs htimbohitu\ Eigenmann, Ann. N. Y. Ac. Sci., VII, 1894, 625 (Marajo.). Eigenmannia Jmmboldti\ Jordan & Evermann, Fishes North and Mid. Amer., 341, 1896. Habitat: ]Marajo, Magdalena and Mamoni. 23. EIGENMANNIA VIRESCENS (Valenciennes). Sternarchus vircsccns Valenciennes, in d'Orb., Vov. Am. Merid., Poiss., 11, pi. 13, fig. 2, 1847. ' Steindachner considers this identical with trosc/tclii. THE GYMNOTID^ 1 73 Sternofygus v/rcsccns^ Kaup, Apod., 137 ; Steindacliner, Die Gymnotidae, 12, 1S68 (Matto Grosso : Rio Negro, Guapore, Alarabitanos ; Irisanga ; Guapore); Giinther, Proc. Zool. Soc. 1868, 229(Xeberos); Giinther, Cat., VIII, 7, 1870 (Suri- nam; Lagoa Santa; Xeberos) ; Cope, Proc. Am. Philos. Soc. 1870, 570 (Pebas; Rio Parana); Cope, Proc. Ac. Nat. Sci. Phila. 1871, 257 (Ambyiacu) ; Liitken, Velhas-Flodens Fiske, 247 and XIX, 1875 (Lagoa Santa and Rio das Velhas) ; Peters, Mb. Ak. Wiss. Berlin, 1S77, 473 (Apure) ; Stein- dachner, Fisch-f. Magd. Stromes, 55, pi. XIV, fig. 4, 1878; Cope, Proc. Am. Philos. Soc. 1878, 682 (Peruvian Amazon) ; Cope, Proc. Am. Philos. Soc. 1894, 93 (Rio Grande do Sul) ; Boulenger, Trans. Zool. Soc, XIV, 38, 1894 (Descalvados). Ci'yptops virescens, Eigenmann, Ann. N. Y. Ac. Sci., VII, 1894, 626; Eigenmann, /. c, 635 (Rio Grande do Sul); Boulenger, Boll. Torino, X, 3, 1895 (Colonia Risso, Para- guay); Boulenger, Am. Mus. Civico, Genova, 1898, 127 (Puerto 14 de Mayo). Eigemnannia virescens^ Eigenmann & Norris, Revista Mus. Paulista, IV, 549 (Piracicaba); Eigenmann & Kenned}'-, Proc. Ac. Nat. Sci. Phila. 1903, 530 (Arroyo Trementina ; Paraguay). Sternofygus tumifrons Miiller & Troschel, Hor. Ichthyol., Ill, 14, 1849, South America. Sicrnofygus lineatus Miiller & Troschel, /. <:., Ill, 14, 1849, Lake Amucu in Guiana; Kaup, Apod., 138; Steindachner, Die Gymnotid^e, 261, 1868. Cr-yftops lineatus^ Eigenmann, Ann. N. Y. Ac. Sci., VII, 1894, 635 (Rio Grande do Sul). Sicrnopygus mia-ostoimts Reinhardt, Videnk. Meddel. Naturf. For. Kjobenh. 1852 or Wiegm. Archj. 1854, ^S^- Stei'nopygiis limbatus Schreiner & Ribeiro, Arch. Mus. do Rio de Janeiro, XII, 6, 1902, Amazonas. Habitat : Rio Magdalena to Rio de La Plata, East of the Andes. The specimens of lineatus mentioned by Eigenmann from Rio Grande do Sul have a more strongly arched ventral profile resembling in this respect ImmboIdtii\ but they have a broad 174 EIGENMAXN AND WARD head, young examples from Paraguay have the same form and differ in this respect from the bulk of the Rio Grande specimens recorded by Eigenmann. 24. EIGENMANNIA AXILLARIS (Giinther). Stcrnopygus axillai'is Giinther, Cat., VIII, 8, 1864, Para; Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., XIV, 1891, 62. Habitat: Para. 25. EIGENMANNIA TROSCHELI (Kaup). Sternofygiisvh-escens, Miiller & Troschel, Hor^e Ichthyol., Ill, 14, 1849 (Guiana); not of Valenciennes. Sternopy gtis t7-oscheli 'K.diVi^, Apod., 139, 1856; Steindachner, Die Gymnotidee, 12, 1868 (Barra do Rio Negro) ; Giinther, Cat., VIII, 8, 1864; Cope, Proc. Am. Philos. Soc. 1878, 682 (Peruvian Amazon); Steindachner, Fisch-f. Magdal., 56, 1878 (note) ; Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., XIV, 1891, 62. Habitat : Amazonas from Manaos to Peru. 10. Gymnotus Linuceus. (Figs. 17-19.) Gymnottis Linnteus, Syst. Nat., ed. X, 246, 1758 (type: Gymnotus carafo Linnaeus); ed. XII, i, 427, 1766 {carapo; electrictts ; albifrons ; rostrattis ; asiaticits). Gymnotus Lacepede. Gymnotus Cuvier Regne Animal, ist ed., II, 235, 1817 (sp. electricus^ cBqiit'labiatus); Giinther, Cat., VIII, 10, 1870 (re- stricted to electrtcus). Sternopygus Muller & Troschel, Horee Ichthyol., Ill, 13, 1849 (inacricrus = cai'apo ; tuniifrons = vif'csccns ; vircsccns ; Unc- ut us ; cequ ila b ia tus). Sternopygus Eigenmann, Ann. N. Y. Ac. Sci., VII, 1894, 326 (restricted to carapo^ to include carapo, cequilabiatiis and obtusirostris). Gyninotcs Gill, Proc. Ac. Nat. Sci. Phila. 1864, 152 {ccquila- biatus). The first species of the Stcrnopygidcc mentioned in literature is the carapo of Marcgrav, THE GYMNOTID^ I75 The name Gynuiotus was apparently introduced by Artedi in his Genera Piscium, p. 25, and Synonymia, p. 43, and the only species mentioned by him is the carafo of Marcgrav. Linnteus, in adopting the name Gynmotus in the lOth edition enumerated only cara^o, but in the 12th edition included in it all the then known species of the family Gyninotidce as well as the electric eel. In his 12th edition he recognized carapo, elcctriciis^ albifrons, rosU'aUis and asiaticus in the order named. The name GymnoUis was used by Bloch for caraj^o and elec- trtctis, by Cuvier for elcctrictis and cBqtiilabiatns, the latter species not known to Linnaeus. It was more formally restricted to clectriais by Swainson. In 1864 Gill properly contended that the genus Gymnotus " had been originally founded solely on the Gymnotus cara^us, and that even after the introduction of the Gymnotus elcctrictis into the system, G. carapus was retained as the first of the genus. * * * The name Gymnotus must be retained for G. cara-pus. * * * " Geographic distribution of the species : Atlantic slope, Mag- dalena south to Rio das Velhas and Paraguay; Pacific slope at Guayaquil. a. Snout pointed, 3 or more in head; profile nearly straight. b. Depth greater than length of head ; upper profile straight or con- vex ; upper lip usually slightly projecting ; a dusky spot over gill-opening carapo^ 26. bb. Depth less than length of head ; upper profile slightly concave ; jaws equal ; a light longitudinal streak ; body with numerous small violet spots; A. 375 to 293 ccguilabiatzcs, 27. aa. Snout very blunt, 3 in head; upper profile convex ; depth greater than length of head; upper lip projecting in adult; A. more than 300 obtusirostris^ 28 . 26. GYMNOTUS CARAPUS Linnaeus. Marcgrav in Seba, Thesaur., Ill, tab. 32, figs. 3-4; Artedi, Genera Pise, 25 ; Synonymia Pise, 43 ; Amoen. Acad., I, 318, t. 14, f. 6. Gymnotus Gronow, Mus. IchthyoL, I, 28, No. 72, 1754; Gro- now, Zoophyl., no. 168, 1863. Proc. Wash. Acad. Sci., June, 1905. 176 EIGENMANN AND WARD Gymnotiis carapo Linnaeus, ed. X, 246, 1858; ed. XII, 427, 1766; Bloch, V, 59, lab. 157, fig. 2; Gronow, Syst., ed. Gray, 22, 1854. Sternopygiis caraptis^ Giinther, Cat., VIII, 7, 1870; Liitken, Velhas Flodens Fiske, 247, and XIX, 1875 (Rio das Vel- has) ; Peters, Mb. Akad. Wiss. Berlin, 1877, 473 (Apure) ; Steindachner, Fisch-f. Magdalenen Str., 4, 1878 (Para); Boulenger, Proc. Zool. Soc. 1887, 282 (Canelos) ; Steindach- ner, Flussf. Siidam., II, 44, 1881 (Amazon from Para toTeffe ; Xingu at Porto do Moz ; Lake Manacapuru ; Rio Branco ; Borba ; Caicara ; Essequibo ; Surinam ; Maroni River in Gui- ana) ; Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., XIV, 1891, 62; Perugia, Ann. Mus. Civico Storia nat. Genova, ser. 2, vol. X, 56, 1891 (Central Chaco) ; Eigenmann, Ann. N. Y. Ac. Sci., VII, 1894, 626 (Marajo) ; Boulenger, Trans. Zool. Soc, XIV, 38, 1896 (Paraguay). Gymnotus macrurtcs, Bloch & Schneider, 522, 1801. Slemopygus macrnrus^ Miiller & Troschel, Hor^e Ichthyol., Ill, 14, 1849; Kaup, Apod., 137; Steindachner, Die Gym- notidae, 11, 1868 (Surinam; Rio Branco: Borba; Caigara) ; Cope, Proc. Ac. Nat. Sci. Phila. 1871, 257, 1872 (Am- byiacu) ; id., Proc. Am. Philos. Soc. 1878, 57 (Peruvian Am- azon). Carapus macrourns^ Cuvier, Regne Animal, ed. I, II, 237, 1817. Caraptis arcnatus Eydoux & Souleyet, V^oy. Bonite, Zool., I, p. 210, pi. 8, fig. 2, 1836. Carapus sangiiinolcnUis Castelnau, Anim. Am. Sud, Poiss., 85, pi. 32, fig. I, 1855, Urubamba or upper Ucayale. SternopygiiS marcgravii Reinh., Vidensk. iMeddel. Naturh. Foren. Kjobenh., 1852; and Wiegm. Arch., 1854, ^^O- Habitat : Orinoco south to Paraguay and Rio das Velhas. 27. GYMNOTUS ^QPILABIATUS Humboldt. Gymnotus cequilabiatus Humboldt, Recueil d'observat., Zool. et Anat. Comp., i, 46, pi. 10; Kaup. Apod., 142 ; Giinther, Cat. VIII, 7, 1870. Slernopygus cequilabialus, Miiller & Troschel, Horaj Ichthyol., THE GYMNOTID^ I77 III, 15, 1849; Steindachner, Fisch-f. Magdalenen Str., 53, pi. XIV, fig. I, 1878 (Magdalena River); id. Fisch-f. Cauca and Guayaquil, 36 and 50, 1880 (Cauca and Guayaquil) ; Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., XIV, 1891, 62; Boulenger, Boll. Univ. Torino, XIII, 1898 (Rio Guayas) ; Steindachner, Denkschr., Acad. Wiss. Wien, LXII, 59, 1902 (Rio Magdalena at Baranquilla). Habitat: Magdalena basin and Guayaquil. 28. GYMNOTUS OBTUSIROSTRIS (Steindachner). Sternopyg'tis obtusirosiris Steindachner, Flussf. Siidam., II, 43, pi. II, fig. 3, 1881, Amazon at Teffe ; Lago Alexo ; Man- acapuru ; Rio Madeira; RioPuty; Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., XIV, 1891, 62. Habitat: Amazonas and Rio Puty. II. Giton Kaup. (Fig. 15.) Carapus Cuvier, Regne Animal, ed. I, 237, 18 17 (sp.). Carafiis Miiller & Troschel, Horse Ichthyol., Ill, 13 {fascia- tus) ; not Carapus Rafinesque. Giton Kaup in Dumeril, Analyt. Ichthyol., 201, 1856. Type: Gymnotus fasciatiis Pallas. Geographical distribution is that of the single species. 29. GITON FASCIATUS (Pallas). Carapo Marcgr., Hist. Pise, 170; Willoughby, Hist. Pise, 115, tab. G 7, fig. 4. Gymnotus Seba, Thesaur., Ill, tab. 32, fig. i. Gymnotus fasciatus^ Pallas, Spicil. Zool., VII, 35 ; Schom- burgk, Fishes of Guiana, 184, pi. 19, 1843 (Guiana). Carapus fasciatus^ Cuvier, Regne Animal, ed. I, 237, 1817 ; Miiller & Troschel, Horag Ichthyol., Ill, 13, 1849; Castel- nau, Anim. Amer. Sud, 85, 1855 (Amazon), Kaup, Apod., 139; Steindachner, Die Gymnotidse, 13, 1868 (Caigara ; Cuyaba ; Marabitanos ; Surinam ; Matto Grosso) ; Giinther, Cat., VIII, 9, 1870 (Capim ; Bahia ; Surinam; British Guiana; Essequibo ; Berbice ; Trinidad; Is. Grenada; Rio Motagua); Hensel, Wiegm. Archiv, 89, 1870 (Guahyba ; 178 EIGENMANN AND WARD Porto Alegre) ; Cope, Proc. Am. Philos. Soc. 1870, 570 (Pebas); Cope, Proc. Ac. Nat. Sci. Phila. 1871 (1872), 257, (Ambyiacu) ; Liitken, Velhas Flodens Fiske, 247 and XIX, 1875 (Rio das Velhas ; Lagoa Santa and Rio San Fran- cisco) ; Cope, Proc. Am. Philos. Soc. 1878, 682 (Peruvian Amazon) ; Boulenger, Proc. Zool. Soc. 1887, 282 (Canelos) ; Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., XIV, 1891, 62; Perugia, Ann. Mus. Civico Storia Nat. Genova, 2nd. ser., vol. X, 56, 1891 (Central Chaco) ; Eigenmann, Ann. N. Y. Ac. Sci., VII, 1894, 626 (Braret) ; Eigenmann, /. c, 635 (Rio Grande do Sul); Cope, Proc. Am. Philos. Soc. 1894, 93 (Rio Grajide do Sul) ; Boulenger, Boll. Torino, X, 3, 1895 (Colonia Risso and Villa Rica, Paraguay) ; Boul- enger, Ann. Mus. Civico, Genova 1898, 127 (Puerto, 14 de Mayo). Giton fasciatus Kaup in Dumeril, Analyt. Ichthyol., 201, 1856; Jordan & Evermann, Fishes North and Mid. Amer., 340, 1896 (Guatemala to Rio de la Plata) ; Eigenmann & Kennedy, Proc. Ac. Nat. Sci. Phila. 1894, 530 (Estancia La Armenia; Campo Grande ; Arroyo Trementina). Gymnottis albns Pallas, Spicil. Zool., VII, 36, Surinam; Bloch & Schneider, 523, 1801. Cara^us albiis^ Kaup, Apod., 140, 1856. Gynmotus brachytirus Bloch, Taf. 157, fig. i, 1787. Gyjmiottcs j)utaol 'Li^ce^hfXe., His. Nat. Poiss., 11, 176, 1800. Gymnotiis cai'a^o^ Bloch & Schneider, 521, 1801. Carapus brachytcrus, Cuvier, Regne Animal, I, 237, 1817. Carapus tn<^qiiilabiattis, Valenciennes, in d'Orb. Voy. Am. Merid., Poiss., 11, pi. 14, 1847 (La Plata). Habitat: Rio Motagua South to Rio de la Plata. THE GYMNOTID.(E 179 TABLE SHOWING KNOWN GEOGRAPHIC DISTRIBUTION BY RIVER BASINS OF THE SPECIES OF GYMNOTID^. a . in 0 -3 cd 0 a a « ■a be a 6 a *u 0 ui cd n .2 '3 0 * * * * * * * * * * * * * * * * * * * * * 1 * cd CO rt 3 ex 2.0-0 Sternarchus brasiliensis " albifrons " bonapartii " macrolepis Sternarchella schotti " balaenops Sternarchogiton nattereri " sachsi Sternarchorhamphus macrostomus... " niuUeri " tamandua Sternarchorhynchus mormyrus (Marabitanos) Sternarchorhj'nchus oxyrhynchus ... " curvirostris Rhamphichthys rostratus " marmoratus " reinhardtii Hypopomus artedii " brevirostris Steatogenys elegans Eigenmannia macrops " humboldti " virescens " axillaris " troscheli Gymnotus carapus " squilabiatus " obtusirostris Giton fasciatus 1 Trinidad. EXPLANATION OF PLATE VIL Fig. I. Ster7iarchus brasiliensis. Photograph by C H. Eigenmann. 2. " albifrons. " " " 3. " macrolefis. After Steindachner. 4. Stertiarchella schotti. " " 5. Sternarchogitoti ?iatiereri. ," " (180) pRoc. Wash. Acad. Sci., Vol. VII. Plate VII. EXPLANATION OF PLATE VIII. Fig. 6. Sternarchorhamphus tamajidua. After Boulenger. 7. " mullcri. After Steindachner. 8. Siertiarc/ior/iytichus mormyrus. " " (1S2) :. Wash. Acad. Sci., Vol. VII. Plate VIII. n EXPLANATION OF PLATE IX. Fig. 9. Sternarchorhynckus ciirvirostyis. After Boulenger. 10. " oxyrhyiichus. After Miiller and Toschel. 11. Steatogejiys elegans. After Steindachner. (1S4) Proc. Wash Acad Sci., Vol. VII. Plate IX. \# EXPLANATION OF PLATE X. Fig. 12. Rhamphichthys marmoratus. Photograph by C. H. Eigenmann. 13. Hypopotnus brevirostris. " " " 14. Etgenma7inia virescens. " " " 15. Git07i fasciatus. " " " (186) Proc. Wash. Acad. Sci., Vol. VII. Plate X. EXPLANATION OF PLATE XL Fig. i6. Etgemnannia humboldtii. After Steindachner. 17. Gymnotus carapus. " " iS. " CEqtiilabiattts. " " 19. " obtusirostris. " " (iSS) Proc. Wash. Acad. Sci., Vol. VII. s ''■'&' ..-■^■;-, Plate XI. 17 ■^:m^^c-^^^^ 18 PROCEEDINGS OF THE WASHINGTON ACADEMY OF SCIENCES Vol. VII, pp. 1S9-249. July 24, 1905 DECLINATIONS OF CERTAIN NORTH POLAR STARS DETERMINED WITH THE MERIDIAN CIRCLE. By Harriet W. Bigelow, Instructor in Astronomy in Smith College;. The stars whose right ascensions and declinations I have observed with the Meridian Circle are those requested by Dr. Auwers in the Astromische Nachrichten, No. 3440. They com- prise a list of 21 stars between 84° 34' and 88° 55' north decli- nation and in magnitude ranging from 5.3 to 7.5. As Dr. Auwers points out, the Berliner Jahrbuch at present gives but 10 stars of declination above 82°, 5 of these being above 85° ; and these are not symmetrically placed in right ascension leav- ing several gaps of 2 or 3 hours when an observer would find no fundamental star of high declination available. The pres- ent observations were undertaken to furnish accurate places of additional stars of high declination for use when such are needed in determining instrumental constants. The observations were begun in October, 1901, and extended through the period to the end of June, 1903. The right ascen- sions have not yet been reduced. The Walker Meridian Circle was built by Pistor and Martins of Berlin in 1854. The telescope tube is heavy, unsymmetri- cal, and shows considerable flexure; the object-glass and eye- ends are not interchangeable, as in many modern instruments. The objective, of 6.3 inches aperture, was examined at the Physical . Laboratory. The focal length, 251.6 cm. or 8 ft. 0.8 in., was determined by measurements on the negative unit Proc. Wash. Acad. Sci., July, 1905. (1S9) 190 BIGELOW planes. The radii of curvature, measured with the sphero- meter, were found to be 165. 7cm. for the outer curve, 274.4 ^^^■ for the inner curve. The structure of the glass was examined by means of Nicol prisms at conjugate foci. For perpendicular position of the prisms the lens instead of being entirely dark .shows irregular light portions extending toward the center, due to irregular polarization in the glass. Practically, however, the lens gives excellent star images for meridian circle work, i. €., small, round disks, of uniform size across the entire field. The graduated circles of the instrument are 27 H iriches in diameter. The fine circle, which was the one employed, is graduated to 2' and is read by 4 microscopes of 16 magnifying power reading to tenths of a second of arc. Each microscope has been furnished with two sets of threads one and a half revolutions apart to eliminate periodic error. For a reading two divisions of the circle were pointed on, the micrometer screw being turned always one half revolution. The readings were corrected for error in the run. The micrometer eye-piece was obtained a few years ago from the Repsolds. It contains 25 verticle threads in groups of 5, and 2 horizontal threads about 5" apart. There is no declin- ation micrometer screw. Settings were made with the tangent screw of the instrument, bringing the star to the point half-waj'- between the horizontal threads. It was usually found possible to make 3 or more pointings with the corresponding readings of the microscopes while the star was crossing the field. The positions off the meridian were symmetrically chosen to avoid error caused by possible inclination of the wires. The reduc- tions to the meridian were made according to the formula , . ^ V sin^ i^/ Z = Z' sin 2 O' — V yr sm 1" where o' is the apparent declination. In this form a second term becomes negligible. (See Leyden Observations, Vol. VI, p. LX.) Tables were made out for each star from which the correction could be taken with the declination and hour angle as arguments. Observations for nadir were made about every 3 hours. These DECLINATIONS OF CERTAIN NORTH POLAR STARS I9I were obtained by turnino- the telescope over a mercury basin and observing the reflection of the horizontal threads by means of a collimating eye-piece. Four settings were made, the mercur}' basin being turned iSo° in the middle of the set. When successive nadirs differed by more than o".50' ^^ was assumed that the difference was directly proportional to the time ; when the difference was less than o". 50 the straight mean was taken. Occasionally during observations for nadir the instrument seemed to move after a setting had been made, showing either that it was under a strain, or possibly that the surface of the mercury changed slightly. The plan was to obtain for each star, both at upper and lower culminations, 2 observations in each of the four following positions: clamp west, direct; clamp west, reflected; clamp east, direct ; clamp east, reflected. This plan was not entirely carried out as the tables show, in part due to the difficulty in obtaining reflected observations. These were often prevented by wind or unsteady seeing. Often, too, reflected observations were prevented by trains on the Michigan Central Railroad, and sometimes by the shutting of a door in another part of the building. Nevertheless, nearly as many reflected observations were obtained as direct. They seem to be quite as consistent among themselves as the direct ; perhaps they are in a sense selected observations. Each night's observing list included at least one of the Berliner Jahrbuch stars. Advantage in combining reflected and direct observations is found in the fact that different sets of divisions on the circle are employed, thus largely eliminating division errors, and in the fact that the sign of the sine flexure is reversed. In the mean of the 4 positions : W. D. ; W. R. ; E. D. ; E. R. ; the first 2 terms of the cosine flexure and the first term of the sine flexure are eliminated. To determine the amount of the flexure the following for- mulas were employed : W. D. ■: = z^ + a' cos z + l>' sin z — (iSo° + iV) + a' W. R. (iSo° — ':)=z^ — a' cos z + 6' sin z— (180° -f ^) + «' E. D. (360° — :) =z.^ + a' cos z — d' sin z — ( iSo° + JV) -{- a' E. R. (iSo° + :) =z^ — a' cos z — d' sin z — (iSo° + A^) + a' 192 BIGELOW The coefficient of cosine flexure found was i".6g^; and of sine flexure, o".ii7. In the case of clamp west tlie circle read- ings increase from the zenith toward the north and the formula for flexure correction is C = ^ + o". 163 — I ."694 cos z -f o". r 1 7 sin z — i ."694 The large cosine flexure was also found b}' Dr. Hall. (See " Reprint from Report of Michigan Academy of Science," 1904-) Corrections for division errors were not applied. Some examination of the circle was made to determine its general character. The mean of the 4 divisions, 0°, 90°, iSo°, 270°, was assumed to be without error. In finding the errors of the intermediate divisions, taking also as a division the mean of 4 marks 90° apart, 2 microscope arms were set 100° apart, 110° apart, etc. Readings were then made on a number of 100° spaces, for instance, distributed symmetrically around the cir- cle; these readings were taken forward and back so as to elim- inate progressive changes in the instrument depending on the time. The mean of these readings was assumed to be the correct 100° space and was used for obtaining the error of the 100^ mark on the circle. The microscopes were afterward changed 180° from their first position and the process repeated. The 2 columns of division errors jriven show the changes produced by placing the microscopes in the two positions. Evidently the effect of gravity is considerable as might be expected from the structure of the circle, which is rather frail. D ivisions. Division Errors. Means. 100° (vs, . 10° etc •) — 0. 1 I — 0.62 -0.36 1 10 20 - 0.33 -0.S4 — 0.5S 120 30 — 0.50 — 0.5S -0-54 130 40 -0.72 — 0.62 — 0.67 140 50 — 0.70 — 0.62 -0.66 150 60 — 0-34 -0.94 — 0.64 160 70 4- 0.06 — 0.26 — 0. 10 170 So 4-0.40 4- 0.02 -f- 0.21 I So 90 0.00 0.00 0.00 Two tabl cs of observe d d eclinations are presen ited, the first DECLINATIONS OF CERTAIN NORTH TOLAR STARS I93 giving the absolute declinations from the circle readings with- out correction for flexure or division errors ; the second giving the declinations of the list stars from comparison with the one or more zero stars observed on the same night. In Table I the observed zenith distances are given, corrected for runs, reduction to the meridian, and refraction. Bessel's refraction tables were employed, as prepared by Professor Eastman of the Naval Observator}-. The standard barometer was repaired and tested a few years ago by the Weather Bureau Office in Washincton. The thermometers also have been tested by them and by the weather bureau official at Lansing. Dur- ing observations the thermometer was hung near the object glass of the telescope, and the readings were corrected w^hen necessary, according to the table of corrections determined by the Weather Bureau Office. The next column in Table I gives the observed zenith dis- tances, reduced to Jan. o.o of the year of observation. These reductions w^ere made with the "Independent Star Numbers" G, H, etc., given for each day in the Berliner Jahrbuch. They were checked by a sufficient number of identical reduc- tions made with the Besselian Star Numbers, A, B, C, D, E, from the Berliner Jahrbuch and the star constants from Dr. Auwers's list in the Astronomische Nachrichten. The zenith distances are then reduced to Jan. o.o, 1900 and the means taken of the different observations of each position. In obtaining these means, a system of weights depending on the number of settings in each case was adopted as follow^s : probable error of one setting 0^.33 ; probable error of nadir determination o".25 ; probable error in refraction tables 0^.30, giving as weights : No. of Settings. Weight. 1 .72 2 .90 3 ^-oo 4 ^-04 5 i-oS 6 1. 10 7 I.I I 194 BIGELOW The reflected observations are also corrected for the position of the mercury basin, the correction being h tan z where h is height of telescope axes above the artificial horizon. This cor- rection is o".04 for upper culmination, and o".03 for lower. The mean of the 4 positions above pole combined with the mean of the 4 below gives the value for latitude corresponding to each star. LATITUDE. List Stars. B.J. St; xrs. Cephei Br. 256 49-35 43 H. Cephei 48-74 Cephei 157 Hs. 48-95 Polaris 48.82 Cephei 15S Hs. 4S.86 Gr. 750 48. 68 Cephei 109 Hs. 48.72 51 H. Cephei 48.80 Urs. min. 4 B 48.71 I H Draconis 48.76 Cephei i3i Hs. 48. 48 30 H. Camelop. 49.10 Urs. min. 3 Hs. 48.43 0 Urs. min. 48-94 32 H. Camel, pr. 4S.70 I Urs. min. 48.65 " "• " seq. 49.08 76 Draconis 48.80 Cephei 135 Hs. 48-75 Mean 48.81 Urs. min. 57 B 48.74 Cephei 3 Hs. 48.60 Cephei Gr. 3548 48. 60 33 H. Cephei 48.72 36 H. Cephei 48.58 39 H. Cephei 48. 61 Cephei i 25 Hs. 48.72 Mean 48.74 The nine zero stars give 48". 81 ; the seventeen others, 48". 74. The value from the nine was given half weight and the adopted value for the latitude of Ann Arbor is 42°i6'48".76. The value found recently by Dr. Hall is 48^.8 (see Astro- nomical Joiirnal, 518). This value of the latitude combined with the zenith distances gives for each star the eight values of declination in the last column of Table I. The mean of the four values above pole, with the mean of the four below, gives the linal value of abso- lute declination. In the case of the live stars not observed in all eight positions, adopted values of declination were found by correcting for flex- DECLINATIONS OF CERTAIN NORTH I'OLAR STARS I95 ure the places obtained and combining them with arbitrary weights as follows : Ccfhci 147 Hs. ] (W. D. + 2 W. R. + E. D.) for declina- tion above pole, combined with equal weight with position below pole. Cephci 149 Hs. \ (2 W. D. + W. R. + E. R.) for declina- tion above pole, and then treated like preceding star. Caniclop. s 664. Mean of the four positions above pole. Urs. inin. 33 Hs. \ (W. D. + E. D.) for position below pole, combined with half weight with observations above pole. £ Urs. mm. W. D. below pole combined with ^ weight with the mean of the remaining observations. In Table II in comparing the stars of the list with the zero stars observed on the same night, differential flexure was ap- plied. No attempt has been made to give weights to the means depending on the number of zero stars employed. The final declinations obtained by the two methods are found to agree closely. Table III gives a summary of the observed declinations to- gether with the declinations given in Newcomb's " Fundamental Catalogue of Stars," and those given in the Berliner Jahrbuch for 1900, so far as the observed stars are found in either cata- logue. The Berliner Jahrbuch for 1906 gives also in the ap- pendix definitive corrections to the places as given in the main catalogue. The last column of Table III has been formed by adding these corrections to the catalogue places, and reducing from 1906 to 1900, employing the Berliner Jahrbuch values for precession without including proper motion. In the first column of observed declinations the five values obtained, as described above, from incomplete sets of observations are bracketed. University of Michigan, Anx Arbor, May, 1904. 196 BIGELOW Table I. — absolute declinations for 1900.0. 43 11. cepiiei. Date of Obs. No. of Set- Zenith Distance. Declina- Year of Obs. tion. tings. 1900.0 1900.0 Obs. 1 Jan. 0.0. 43=^26' 43° 26' 85°43' Weighted Mean. W.D. Dec. 1 1, '01 3 88. '01 48-38 28. 92 38.92 1 7! 68 -o W.R. Dec. 5. '01 I 84.27 45.87 26.41 26.46 15.23 d. Dec. 6, '01 I S4.49 45-90 26.44 ^ E.D. 0 Nov. iS, '01 75.60 41.67 22.31 22.21 10.97 Oct. '01 3 70-35 45.58 26.12 E.R. Nov. 9. '01 3 75-46 44-49 25.03 25.61 H-37 Nov. 26, '01 I 81.16 45-03 25-57 25.80 14.56 51° 58' 51 ^59' W.D. Mar. 31^ '03 3 54-97 59.'7o 58'.oS 5842 1 3'.' 8 3 May 29, '03 2 70.27 60.38 58.76 A W.R. 0 Mar. May 31. 29, '03 '03 2 I 53.80 68.73 58.53 58.84 56.91 57-22 57-08 14.16 ^ May 9^ '02 I 80.19 76.18 55-IO S E.D. May 16, '03 I 80.59 75.23 54-15 54-65 16.59 Apr. 29, '03 3 60.20 56.30 54.68 E.R. Feb. May 21, 8, '03 '03 3 3 41.79 64.94 57.70 58.88 56.08 57.36 56.67 14.57 56.71 14.53 14.55 DECLINATIONS OF CERTAIN NORTH POLAR STARS 197 Table I.— ABSOLUTE DECLINATIONS FOR 1900.0. POLARIS. Zenith Distance. Date of Obs. No. of Set- * Declina- Year of Obs. tion. tings. Obs. Jan. 0.0. 1900.0. 1900.0. 46°29' 46 °29' 88°46' Jan. 8, '03 4 100.82 78.42 40.92 Weighted Mean. Oct. 7, '03 4 90.04 77-75 40.35 Oct. 8, '03 5 93. 38 79.69 43.19 W.D. Oct. Oct. 9, '03 38, '03 3 4 91-31 97-05 78.21 76.81 40.71 39-31 4o.'58 29-34 Oct. 29, '03 4 97.81 77.24 39-74 Oct. 30, '03 5 98.S9 77-99 40-49 Oct. 31, '03 7 99.71 78.47 40.97 0 Dec. 6, '01 3 91.38 55-7S 37-02 '0 Oct. 30, '02 5 91-15 74.02 36-52 ^ W.R. 4) Oct. 31, '03 3 93.19 74.64 37-H 37-35 26.11 > 0 Oct. 34, '03 6 94.53 75-73 38-23 Dec. iS, '03 3 110.89 75.06 37-56 Nov. 13, '03 4 98.91 73-3S 35.S8 Nov. 3 1, '03 3 103.73 74.06 36-56 35-59 24-35 E.D. Nov. 34, '03 5 103.34 72.76 35-26 Nov. 28, '03 3 103.86 73-iS 35.68 Feb. 5. '03 2 1 10.06 90.80 34-57 Dec. 3, '01 I 91.26 56.69 37-93 E.R. Nov. 19, '02 3 103.08 75-11 37.61 37-72 26.48 Nov. 21, '02 3 103.72 75-05 37-55 37.81 26.57- 48° . 4S '56' Apr. II, '02 I 65-31 7046 47-96 Apr. 24, '03 5 6S.91 70.05 47-55 Apr. 28, '02 2 70-55 70.60 48. 10 June 8, '02 I 79.31 70.52 48.03 // ^^ W.D. Mar. 21, '03 4 40.31 49-77 46.00 46.96 24.38 jj Mar. 25, '03 2 41.90 50.19 46.42 '0 Mar. 28, '03 3 43.03 50.28 46.51 ^ Mar. 29, '03 3 42.81 49-72 45-95 s ■ May 29» '03 2 60.23 50.56 46-79 W Apr. 29, '02 3 66.62 66.41 43-91 June 3 5 '02 3 74-55 66.40 43-90 W.R. June 8, '02 3 74-31 65.63 43.12 44-03 27.31 Mar. 25^ '03 3 39-91 48. 30 44-43 May 29» '03 0 5S.17 48.50 44-73 198 BIGELOW Table I. — absolute declixations for 1900.0. polaris. — Co7i- tinued. Zenith Distance. Date of Obs. No. of Set- Declina- Year of Obs. tion. tings. Obs. Jan. 0.0. 1900.0. 1900.0. 48= '55' 48=56' May 9. '03 2 67-37 64-34 41:84 Weighted Mean. May 13. '02 5 6Z.s^ 64.70 42.30 May 16, '02 2 69.26 64.69 42.19 E.D. May Mar. 24. I, '03 '03 5 3 70.61 31-44 64-23 46-35 41-73 42.58 42.06 29! 18 0 Apr. 28, '03 2 48.06 45-62 41.85 p Apr. 29, '03 3 48.41 45-70 41-93 May 8, '03 2 50-97 45-89 42. 12 May % '02 I 69.74 66.71 44.31 M May 25, '02 3 73-58 67.04 44-54 Feb. 24, '03 3 32-59 48-77 45.00 E.R. Feb. 25, '03 3 33-04 48.99 45-22 45-09 26.15 Mar. 2, '03 4 34-29 48-93 45.16 Apr. 28, '03 4 52.05 49.61 45-84 May 8, '03 I 54.08 49.00 45-23 44-54 26.70 26.64 DECLINATIONS OF CERTAIN NORTH POLAR STARS 199 Table I. — absolute declinations for 1900.0. cephei br. 256. W.D. P W.R. > o < E.D. E.R. W.D. ^ W.R. o S E.D. E.R. Date of Obs. Oct. S Oct. 28 Oct. 29 Jan. 22 Oct. 21 Oct. 24 Jan. 23 Jan. 26 Nov. 24 Nov. 28 Dec. 2 Nov. 19 Nov. 21 June 8, '02 Mar. 21, '03 Apr. 29, '02 June 3, '02 May 9, '02 May 13, '02 May 16, '02 May 25, '02 Feb. 24, '03 No. of Set- tings. Zenith Distance. Year of Obs. obs. I Jan. o.o. 4o°48' S7.23 92.94 92.87 96.44 87.41 S9-75 109.85 97-05 98.36 88.25 9S.71 99.69 79.21 77-75 77-33 75-59 74-74 76.02 91-54 93-90 72.56 72.63 58.65 75-84 76.17 54°36' 76.65 39-56 73-98 65-79 67-39 68.01 72. 86 33-34 67.74 49-23 65-57 65. 88 63-37 63.91 63-77 66.54 4S.85 44-73 43-27 42.85 4o°48' i'ei M 43.66 41. II 40.26 41-54 39.82 42.18 38.08 38.15 41.41 41.36 41.69 Weighted Mean. 41.06 38.11 41-54 41.09 54°37' 42.22 40.95 40.05 40.36 37-85 3S-39 38-25 41.02 40.57 41.58 40.22 38.19 40.83 40.21 Declina- tion. 1900.0. 83°o5' 32-42 29.82 26.87 30.30 29.85 29.66 31.02 33-05 30.41 3^-03 30.44 200 BIGELOW Table I. — absolute declinations for 1900.0. cephei 147 hs. Date of Obs. No. of Set- tings. Zenith Distance. • Year of Obs. Obs. 1 Jan. o.o. 1900.0 1900.0 42° 16' 42° 16' Weight' d Mean. S4°33' W.D. Dec. Jan. II, '01 8, '03 3 3 75 -S3 S3-15 54-17 67.99 40.66 40.99 40-83 29-59 (^vt. I) 6 W.R. "o Dec. Nov. Nov. Feb. 5. '01 13, '03 28, '03 5. '03 I I 2 3 71-57 72.60 76.95 90. 98 51-79 63-36 62.19 75-23 38.28 36.36 35-19 34-75 38-32 35-34 27.08 4-.281 > 0 < E.D. 27.36 (Wt. 2) 24.10 (wt. I^ E.R. 53° 08' 53^^ 09' [27.10] W.D. June Mar. 14, '03 29. '03 3 I 90.17 56.53 80.39 65-73 47-39 46.21 46.90 24-34 W.R. June Mar. Mar. 3^ '02 25^ '03 28, '03 I 2 2 84.67 54.18 54-55 77-37 64-35 64.00 44-37 44-83 44.4S 44.61 26.63 0 I E.D. May May Apr. 9, '02 16, '02 9, '03 I I 3 75-79 77-34 54-32 75-40 74.88 60.56 42.40 41.88 41.04 41.69 29-55 '0 E.R. May May June Apr. 21, '02 22, '02 26, '02 28, '03 2 I I I 81.83 82.11 89.46 65-55 77-94 77-95 77-54 66.16 44-94 44-95 44-54 46.64 45.21 26.03 44.60 26.64 [26.S7] ' Cos flexure and absolute term. DECLINATIOxMS OF CERTAIN NORTH POLAR STARS 201 Table I. — absolute declinations for 1900.0. cephei 149 hs. Date of Obs. No. of Set- tings. Zenith Distance. Declination 1900.0. Year of Obs. Obs. Jan. o.o. igoo. 0. 44°o3' 44°o3' 86°i9'' Weighted Mean. W.D. Dec. Jan. II, '01 8, '02 I 3 39 -So 47.48 22.63 34-43 10.77 10.74 IO-75 59-5 1 -2.75^ '0 56.76 (wt. 2) ii W.R. 0 Jan. Feb. 23, '02 15, '02 3 2 47-34 47.41 31.68 29.92 7-99 6.23 7.20 55-96 < E.D. Nov. 24, '02 3 40.15 31.40 [7.71? E.R. Nov. Nov. 19, '02 31, '02 3 2 38.76 39.60 31-73 31.88 S.04 8.19 8.15 56.91 [56.60] 51 = 22' 51 ■"J June 8, '02 2 61.36 53-17 16.86 W.D. June June 13, '02 14, '02 I 3 62.99 63.58 53-67 54.02 17.36 17.71 17-32 53-92 -3 W.R. Apr. June 29, '02 3' '02 3 3 46.11 56.86 49.69 50.06 13.3S 13-75 13-59 57-65 |e.d. May May 8, '02 13, '02 I 3 44.87 48. 02 45.68 47-30 9-37 10.99 10.48 60.76 May 25, '02 2 51.40 47.12 10.81 E.R. May May 21, '02 23, '03 5 3 53-93 55-22 50.81 51.80 14.50 15-49 15.01 56.23 14.10 57-H [56.87] ^ There is evidently a large error in this value; probably due to an error in the original ecord. 2 Cos flexure and absolute term. 202 BIGELOW Table I. — absolute declinations for 1900.0. gr. 7^0. Date of Obs. No. of Set- tings. Zenith Distance. Declina- Year of Obs. Obs. 1 Jan. o.o. 1900.0. tion. 1900.0. 43°oo' 43°oo' 85°i7' Weighted Mean. W.D. Oct. Oct. 38, 30, '02 '03 3 3 57-07 57-05 62.55 63.01 43-29 42.75 43-02 3178 •^ W.R. 0 > Jan. Feb. Dec. Jan. 33, 15, 18, 36, '03 '03 '03 '03 3 I 3 3 71.12 74-13 69.97 80.53 58.06 58.35 58.83 69.20 38.80 39-09 39-56 40-34 39-51 28. 27 0 ^ E.D. Nov. Feb. Feb. 34, 5^ 13. '02 '03 '03 3 3 3 60.51 78.73 79-15 57-29 66.07 65.65 38-03 37-21 36.79 37-36 26.13 E.R. Nov. 31, '02 3 61.67 59-49 40.23 40.27 39.03 40.04 28.80 52= 25' 52^ '25' W.D. June June June Mar. 8, 13. 29, '02 '03 '02 '03 I I 3 4 31-91 34-H 35-47 5.50 24-35 25-36 26.41 15-51 43.61 44.63 45-67 44-37 44-64 26.60 6 W.R. 'o Apr. June June Mar. 29, 3. 5r 28, '03 '02 '02 '02 I 3 3 3 18.79 39.71 39.83 4.48 23.10 23-5^ 33.03 14.73 42-36 43.77 43.38 43-5S 43.81 2S.43 M E.D. May May Apr. Apr. 8, 25, 9, 27, '02 '02 '03 '03 I I 2 2 17.08 24-36 3. 38 S.45 18.61 20.77 10.97 II. 15 37-87 40.03 39 -S3 40.01 39-49 31-75 E.R. May May June June 21, 24, 26, '02 '02 '02 '02 I I I 2 25-92 27-15 36.63 35-48 23-52 24-43 25.12 23-57 42.78 43-69 44-38 42.83 43-42 27.82 42.59 2S.65 28.72 DECLINATIONS OF CERTAIN NORTH POLAR STARS 203 Table I. — absolute declinations for 1900.0. cephei 157 hs. Date of Obs. No. of Set- tings. Zenith Distance. Declina- Year of Obs. Obs. [ Jan. o.o. 1900.0 tion. 1900.0 43^ '33' 43 ^32' Weighted Mean. 85°49' W.D. Feb. 22, '02 Feb. 24, '02 3 3 2c;.I2 24. 88 11.70 11.31 60.91 60.52 60.72 49-4S i W.R. Oh Feb. 13, '02 Feb. 15, '02 4 3 20.25 20.55 7.70 7.76 56.91 56.97 56.98 45-74 1 E.D. < Mar. 5, '02 Mar. 6, '02 Feb. 5, '03 3 I 2 19.64 1S.93 19.87 5.82 5.10 10.60 55-03 54-31 54-46 54-64 43-40 E.R. Feb. 24, '03 Feb. 26, '03 I 2 24.76 25.01 13-24 13-39 57-IO 57-25 57.22 45-98 57-39 46.15 5i°52' 51^ '53' W.D. June 9, '02 June 13, '02 Mar. 29, '03 3 5 4 S3.48 84.62 60.47 76.87 76.83 70.65 27.66 27.62 26.79 27-36 43-S8 2 W.R. June 3, '02 June 5, '02 Mar. 28, '03 3 I 3 7S.36 7S.70 58.80 73-54 73-27 69.12 24-33 24.06 25.26 24-63 46.61 m E.D. June 16, '02 June 17, '02 3 3 S0.77 79-56 72. IX 70.62 22.90 21.41 22.16 49.08 E.R. June 24, '02 June 26, '02 4 3 85.12 84.90 74-23 73 -43 25.02 24.27 24.68 46-56 24.71 46-53 46.34 204 BIGELOW Table I. — absolute declixations for 1900.0. cephei 15S hs. > o W.D. W.R. E.D. E.R. W.D. & W.R. Date of Obs. E.D. E.R. Jan. 16, '03 Feb. 15, '03 Feb. 22, '02 Jan. 33, 'o3 Feb. 13, '02 Mar. 4, '02 Mar. 5, '03 Mar. 6, 'o3 Feb. 34, '03 Feb. 35, '03 Mar. 3, '03 June 5, '03 June 9, 'o3 Mar. 39, '03 June 3, 'o3 Mar. 28, '03 June 16, '02 June 17, '02 May 31, '03 May 33, '02 No. of Set- tings. Zenith Distance. Year of Obs. Obs. j Jan. o.o. 43°53' 13.84 18.93 21. 01 10.45 15.04 15-50 16.38 19.20 18.69 19.09 19-55 9.29 S.65 9.80 5-27 5.08 3-45 4.37 7-05 9.07 9-36 9-38 24.39 24-33 5.10 52°34' // 19.82 18.65 14.94 17.87 3-96 21.06 20.93 17.14 17. 1 1 14.01 13.89 13.37 13.85 17.19 16.87 Declina- tion. 1900.0. 42^ '51' Weighted Mean. 85=08' 64.07 63-43 64.5S 63-97 52-73 60.05 59.S6 59-99 48.75 58.23 59-05 58.64 47.40 61.83 61.39 61.58 61.63 50-39 61.60 61.06 49.82 52 =34' 35.04 23.87 33:88 47-36 22.73 19.33 31.67 30.4S 50.76 18.49 18.07 1S.38 52.96 33.41 33.09 22.27 48.97 21.23 50.01 49.92 DECLINATIONS OF CERTAIN NORTH POLAR STARS 205 Table I. absolute declinations for 1900.0. 51 h. cephei. Date of Obs. No. of Set- tings. Zenith Distance. Year of Obs. Obs. 1 Jan. 0.0. 1900.0. tion. 1900.0. 44°55' 44°55' 87'^i2' Weighted Mean. W.D. Mar. Mar. 29, '02 25. '03 I 3 34-87 38.98 25-43 20.52 34-93 34-84 34:88 23-64 W.R. Feb. 15^ '02 2 25.09 21-52 31.02 31.06 19.83 0 ? E.D. 9 Mar. Mar. Feb. 5^ '02 24, '02 6, '03 I I 3 26.24 28.11 H-38 19.03 18.74 14.30 28.52 28.24 28.62 38.48 17.24 0 42 < E.R. Mar. Mar. Feb. Feb. Feb. Mar. 6, '02 19, '02 i3» '03 25, '03 26, '03 2, '03 3 3 3 3 3 4 30.89 32-47 19.64 23.38 22-77 34.40 23.48 23-56 17.60 18.49 17-74 18.57 32.98 33-o6 31.92 32.81 32.06 32.89 32.66 21.42 31-77 20.53 50= 30' 50^ '30' W.D. June June June 13, '02 9/03 14^ '03 3 2 I 68.16 69.49 70.93 64-27 66.12 66.09 54-77 51.80 51-77 52^92 18:32 £ W.R. 0 June June June 27, '02 9, '03 14. '03 I I 2 68.30 69.13 69.68 60.04 65-75 64.85 50-54 51-43 50.53 50.84 20.40 ra E.D. June Apr. 17, '02 27, '03 I 4 62.41 55 -60 57-23 62.37 47-73 48.05 47.93 23.32 E.R. June June 26, '02 25^ '03 3 3 67.79 73-90 59.83 65-57 50-33 51-25 50. S3 20.42 50.63 20.63 20.57 2o6 BIGELOW Table I. ABSOLUTE DECLINATIONS FOR I 900.0. ( :ephei I 09 HS. Date of Obs. No. of Set- tings. Zenith Distance. Declina- Year of Obs. Obs. j Jan. 0.0. 1900.0 tion. 1900.0 42° 03' 42^ 03' Weighted Mean. 84°2o' W.D. Mar. 39, '03 "Apr. II, '03 3 3 51-95 53.46 45-37 45-07 64.40 64.10 64.26 53 -02 f W.R. Feb. 15, '03 Mar. 3 1, '03 2 2 37-92 36.83 39-89 31-56 58.92 60.14 59-57 48.33 1 E.D. < Mar. 4, '03 Mar. 5, '03 3 3 42.26 40.94 39.86 38.31 5S.89 57-34 58.12 46.88 E.R. Mar. 19, '03 Mar. 37, '03 3 3 48.09 49.80 43. So 43-44 61.83 62.47 62.19 50.95 61.04 49.80 53°22' 53°22' W.D. June 5, '03 Oct. 6, '03 3 2 41.96 76.31 42.39 43-30 23-36 24-27 23-79 47-45 fS W.R. o Oct. 7, '03 Oct. iS, '03 Oct. 20, '02 June 9, '03 I I I 2 73-04 75-10 74-47 49.84 40.01 40.99 40.33 49.28 20.98 21.96 21.19 20.70 21.21 50.03 « E.D. June 17, '02 Sept. 15, '02 2 2 40. So 66.86 37-99 37-59 18.96 18.56 18.76 53.48 E.R. June 36, '03 2 46.79 41-34 22.31 22.34 48.90 21.52 49.72 49.76 DECLINATIONS OF CERTAIN NORTH POEAR STARS 207 Table I. — .vbsolute declinations for 1900.0. urs. min. 4 b. Date of Obs. No. of Set- tings. Zenith Distance. Declina- Year of Obs. Obs. 1 Jan. 0.0. 1900.0. tion. 1900.0 46°3S' 46 °39' 88°55' Weighted Mean. W.D. Mar. 29, Mar. 25, '03 '03 2 2 61.30 49-13 54-32 42.89 14.20 12.83 13-52 62 [28 . W.R. Mar. 31, Mar. 25, '03 '03 3 4 45-83 46-39 40.17 40.15 10. II 10.09 10.14 58.90 0 1 E.D. < Mar. 21, Mar. 24, Mar. 35, Feb. 5, '02 '02 '03 '02 I I I 4 54-09 53-31 54-41 32.12 48.15 46.94 47.91 37-66 8.03 6.S2 7-79 7.60 7.60 56.36 Feb. 6, '03 3 32-57 37-79 7-73 E.R. Feb. 5, Feb. 34, '03 '03 4 4 35-56 41.20 41.10 41.05 1 1 .04 10.99 11.06 59-82 10.58 59-34 48= '47' 48 '47' W.D. June 37, Sept. 22, Sept. 26, '03 '03 '03 I 3 I 39-65 66.61 67.01 34.18 35-15 34-79 14.30 15-27 14.91 i4.'S8 56^36 £ W.R. June 27, June S, '03 '03 4 3 36.29 40-53 30.82 40.80 10.94 10.86 10.93 60.31 i E.D. June 17, '02 3 31.92 29.51 9-63 9-63 61.61 E.R. June 36, June 35, '03 '03 3 2 36.96 47-73 3 1. So 43-" 11.92 13-17 12.54 58.70 12.00 59-24 59-29 208 BIGELOW Table I. absolute declinations for 1900.0. cephei 121 hs. Date of Obs. No. of Set- tings. Zenith Distance. Declina- Year of Obs. Obs. 1 Jan. o.o. 1900.0. tion. 1900.0. 42°i7' 42= 18' 84=34' Weighted Mean. W.D. Feb. Mar. 23 29, '02 '02 3 3 40-32 48.02 4548 44.49 13.12 12.13 12.62 61.38 6 W.R. '0 Apr. Mar. Mar. 25^ 28, '02 '03 '03 2 I 2 47.70 31-78 31-91 41.92 28.63 28.18 9.56 10. II 9.66 9-79 5S.55 0 1 E.D. < Mar. Mar. Feb. 4. 5i 13. '02 '02 '03 I 3 4 35-91 36-54 17.71 38-17 38-52 25-39 5-81 6.16 6.87 6.34 55-IO E.R. Mar. Mar. Mar. 21, 25 . 27, '02 '02 '02 3 3 3 44-15 46.40 46.26 42.18 43.61 43-09 9.82 11.25 10.73 10.64 59-40 9.85 58.61 53 ^oS' 53' '08' W.D. Sept. Oct. Oct. 22, I, 9^ '02 '02 '02 3 I 4 73-65 74.48 77-43 43-37 41.90 43.07 15-73 14.26 ' 15-43 15-23 56.01 6 ^ W.R. 0 June Oct. Oct. June 27, 18, 21, 8, '02 '02 '02 '03 2 I I I 41.85 77.12 77.27 52.20 39-17 41.06 40.72 54.88 11-53 13-42 13.08 13.40 I2.SI 58.43 pq E.D. June Sept. Nov. Nov. 17. 16, 20, 21, '02 '02 '02 '02 3 I 3 3 37-94 67.92 78.04 77-86 37.88 39-29 39-11 38.93 10.24 11.65 11.47 1 1.29 II. 13 60.11 E.R. June 26, '02 3 43.60 41.20 13-56 13-59 57-65 13-19 58.05 58.33 DKCI.INATIONS OF CERTAIN NORTH POLAR STARS 209 Table I ABSOLUTE ] DECLINATIONS 5 FOR I 900.0. I H. DRACONIS. Date of Obs. No. of Set- tings. Zenith Distance. Declina- Year of Obs. Obs. 1 Jan. 0.0. 1900.0 tion. 1900.0 39° 28' 39^ 49' Weighted Mean. 8i°46' W.D. Apr. 4, '03 3 37-7S 34-46 21.12 21.12 9.88 6 W.R. Apr. 34, Mar. 21, '02 '03 I 2 52-50 31-57 47.20 31.26 18.30 17.92 18.13 6.89 9 E.D. 0 Apr. 7, Apr. 9, '03 '03 2 2 32-73 32-54 28.86 28.27 15-52 14-93 15.22 3-98 < E.R. Mar. 31, Feb. 5, Feb. 6, Mar. 3, Mar. 8, '02 '03 '03 '03 '03 3 2 3 2 I 47.02 19-52 19.48 27.17 28.02 47-32 31.98 31.68 31.89 31-17 18.42 18.64 18.34 18.55 17-83 18.43 7.18 18.32 6.98 55°57' 57' W.D. June 37, Oct. I, '02 '02 2 38^11 69.63 36:98 38.22 5.88 7.12 6-43 4'.8i 2 W.R. Oct. iS, Oct. 34, '03 '03 71-51 71.89 36.00 35-03 4.90 3-93 4-45 6.79 1 E-I^- June 17, Sept. 15, '03 '03 31.88 58.59 32-99 31.84 1.89 0.74 1.33 9-92 E.R. June 35, '03 2 51-30 51-51 4.85 4.88 6.36 4-27 6.97 6.98 2IO BIGELOW Table I. absolute declinations for 1900.0. 30 h. camelop. Date of Obs. No. of Set- tings. Zenith Distance. Declina- Year of Obs. Obs. Jan. o.o. 1900.0. tion. 1900.0. 40^ =46' 4o°47' 83^3' Weighted Mean. W.D. May Mar. 2, 21, '02 '03 2 3 44-53 19. So 39-53 22.13 15-74 16.46 16.10 64.'86 6 -o W.R. Apr. Mar. Mar. 25^ 28, '02 '03 '03 3 2 3 3S.9S 17.90 19-39 36.46 19.10 19.78 12.67 13-43 14. II 13-44 62.20 0 3 E.D. Feb. Apr. 26, 9, '03 '03 3 2 7-52 19-45 16.90 16.90 11.23 11.23 11.23 59-99 E.R. Feb. Apr. 24. 7, '03 '03 I 2 9.62 21.80 54' 19.63 19.70 '39' 13.96 14.03 54 14.04 13.70 =39' 62.80 62.46 W.D. Oct. Oct. 4^ 6, '01 02 2 I 59.00 76.5S 2S.07 45-99 9-96 9.78 9.S8 6 1. "36 i W.R. 0 Oct. Oct. Oct. 5' 7. 21, '01 '01 '02 2 2 3 57-31 58.38 79-27 26.05 26.47 44.27 7-94 8.36 8.06 8.15 63.09 1 E-^- Oct. Oct. Nov. 23: 25, 21, '01 '01 '02 3 2 2 60.04 61.41 84.30 23.48 24-33 43-04 5-37 6.22 6.83 6. II 65-13 E.R. Nov. Nov. 30. 20, '01 '02 2 2 69.02 86.14 25.81 45.01 7.70 S.80 8.28 62.96 8.10 63.14 62.80 DECLINATIONS OF CERTAIN NORTH POLAR STARS 211 Table I. — absolute declinations for 1900.0, camel, s. 664. Date of Obs. No. of Set- tings. Zenith Distance. Year of Obs. Obs. 1 Jan. o.o. 1900.0. 1900.0. 43 ^52' 43 =54' Weight'd Mean. 86° 10' W.D. Mar. 21, '03 Mar. 29, '03 3 3 68.56 71.64 73.66 73-33 10.95 11.62 11". 2 8 60.04 -^ W.R. Mar. 28, '03 Mar. 31/03 3 3 69.50 69.88 71.49 70.99 9.78 9.38 9-56 5S.32 > E.D. Feb. 6, '03 Feb. 26, '03 3 3 50-59 55-93 67.86 67-35 6.15 5.64 5-90 54.66 < E.R. Feb. 21, '03 Feb. 25, '03 Mar. 2, '03 3 2 3 57-25 59.85 61.03 70,22 71.58 71.18 8.51 9.87 9-47 9-33 58.09 9.03 [57.78] 212 BIGELOW Table I. — absolute declinations for 1900.0. URS. MIN. 3 HS. Date of Obs. No. of Set- tings. Zenith Distance. Declina- Year of Obs. Obs. 1 Jan. o.o. 1900.0 tion, igoo.o 45° 57' 45= 58' Weighted Mean. 88°i5' W.D. Apr. Apr. Mar. II, '02 24, '03 38, '03 5 I 3 47^28 49-85 24.80 49.98 48.93 39.76 39.87 38.81 39.60 29-50 iSr26 6 W.R. 3 Apr. Apr. 10, '03 15^ '02 6 0 43.16 44-25 46.15 45-78 36.04 35.67 35.90 14.66 0 0 E.D. < May May May Feb. 13, '03 33, '03 35, '03 6, '03 I 3 4 48.03 49.64 50.20 4.41 43.91 43-13 43-34 23-58 32.80 33.03 23-23 33.43 23-15 II. 91 E.R. May Feb. Mar. 34, '03 25, '03 2, '03 3 3 3 53-39 12.09 14.10 46.64 36.65 37.34 26.53 36.49 37.08 26.73 15-49 36.33 15.08 49^ 38' 49' '27' W.D. Dec. Jan. Oct. II, '01 8, '03 I, '03 I 3 4 62.29 64.89 58.43 19.56 40.37 39.60 59-61 60.38 59-71 59-93 11.31 W.R. Oct. Oct. 20, '03 24, '02 3 0 61.88 64.19 35-92 36-79 56.03 56.90 56.47 H-77 ^ E.D. 0 Oct. Nov. Nov. 28, '01 18, '01 24, '03 3 I 3 44.49 50.91 70.72 13-56 13-34 33-69 53-61 53-39 53-80 53-62 17.63 0) E.R. Oct. Oct. Nov. Nov. Nov. Nov. 33, '01 39, '01 9, '01 13, '03 19, '03 31, '03 I I I I 3 3 46.08 49.73 52-13 70.59 73.83 73-09 17.37 18.44 17.33 36-89 37-11 36-84 57-32 58-49 57-27 57-00: 57-22 56-95 57-38 13-86 56.S5 H-39 14.74 DECLINATIONS OF CERTAIN NORTH POLAR STARS 213 Table I. — absolute declinations for 1900.0. 32 11. camel, pr. Dateof Obs. No. of Set- tings. Zenith Distance. Declina- Year of Obs. Obs. 1 Jan. o.o. 1900.0. tion. 1900.0. 4i°39' 41 °4o' 83°57' Weighted Mean. W.D. Apr. Mar. Mar. II, '02 21, '03 29^ '03 3 3 I 71-55 46.73 48.46 76.33 55-91 55- 10 55-50 54-69 53.88 54-77 43 -'53 4 ^^'•^^• Apr. Mar. 29, '02 -5. '03 2 3 73-93 44.81 73-35 53.73 52-53 51-50 52.06 40.83 2 E.D. < May May Mar. 16, '02 23, '02 I> '03 I 3 3 74.68 75-50 36.09 70.00 69.66 51-13 49.18 4S.84 49.91 49-30 38.06 E.R. Feb. Feb. Apr. 6, '03 25, '03 28, '03 3 I 2 33-63 3«-63 53-55 54-69 55.08 52.33 53-47 53.S6 53-21 41.97 52-34 41.10 53' 45' 53 ^45' W.D. Jan. Oct. 8, '03 8, '02 3 4 96.33 88.81 72. 28 72.17 33-10 32-99 33-04 38.20 1 W.R. Oct. Dec. 34, '03 18, '02 3 3 91-51 107.66 68.59 68.68 39.41 39.50 29.49 41-75 S E.D. Nov. Nov. 12, '02 28, '02 3 3 96-45 101.51 66.94 67.07 27.76 27.89 27. 82 43-42 E.R. Dec. Nov. 2, '01 19, '02 3 3 S8.73 101.13 50.S7 69-34 31.28 30.16 30.72 40.52 30.27 40.97 41.03 Proc. Wash. Acad. Sci., July, 1905. 214 BIGELOW Table I. — absolute declinations for 1900.0. 32 h. camel. seq. Date of Ot )S. No. of Set- tings. Zenith Distance. Declina- Year of Obs. Obs. j Jan. o.o. 1900.0 tion, tgoo.o 41° 39' 41' 40' Weighted Mean. 83=57' W.D. Apr. Apr. Mar. 24> 38, 29, '02 '02 '03 3 2 57-45 58-31 30.60 56.63 58.01 37-25 35-80 37-19 36.01 36'3i 25-07 o- W.R. 0 June June s, '02 '02 2 3 62.90 62.08 55-27 53-93 34-45 33-" 33.7S 22.54 % E.D. May May 9> 13. '02 '02 I 3 55-61 5<5-03 52.46 51-99 31.64 31-17 31-55 20.31 < Mar. I, ^03 I 18.16 33-21 31-97 May 25, '02 I 61.88 55-53 34-72 E.R. Feb. Mar. 24. -> ^03 '03 2 3 19.24 22.32 35-55 37.10 34-31 35.86 35-27 24.03 Apr. 28, '03 I 39-92 37-33 36.09 34-23 22.99 53^46' 1 53^ 45' W.D. '0 Oct. Oct. Oct. 9^ 30, 31. '02 '02 '02 2 3 3 46.76 54-05 55-30 29.76 29.14 30.02 50-58 49.96 50.84 50.46 20 '.78 Oh ^ W.R. 0 Oct. Oct. I1 21, '02 '02 I 3 41.87 47.21 25-63 25.64 46.45 46.46 46.48 24.76 tt E.D. Nov. 24, '02 3 57-50 24.22 45-04 45-04 26.20 E.R. Nov. 21, '02 3 59-97 27.58 48.40 48-43 32.81 47.60 23.64 23-31 DECLINATIONS OF CERTAIN NORTH POLAR STARS 215 Table I. — absolute declinations for 1900.0. cephei 135 hs. Dat« : of Obs. No. of Set- tings. Zenith Distance. Declina- Year of Obs. Obs. Jan. o.o. 1900.0. tion. 1900.0. 40 °57' 40=58' 83°i5' Weighted Mean. W.D. Apr. June Mar. 38, '03 8, '03 25. '03 I I 3 SO. 8c; 61.56 24.70 53.51 53-07 34-69 28:55 39.11 28.75 28'.'8o 17-56 p W.R. Apr. June 39, '03 3, '02 3 3 48.63 57-87 49-99 50.27 26.03 26.31 36.30 14.96 > 1 E.D. May May May 9, '03 13, '03 16, '03 3 3 I 48.49 50.19 51.82 46.89 47.48 48.30 22.93 23-52 24-34 23-54 13.30 E.R. May Feb. 35, '03 25. '03 3 3 56.38 15-07 50-56 32.11 26.60 26.17 36.42 15.18 36.24 15.00 54 '28' 54 ^2/ W.D. Jan. Oct. Oct. 8, '03 8, '03 9, '03 I 4 3 55-52 43-73 42-94 34.00 35-14 33-98 57-96 59.10 57-94 58:38 12:86 "o W.R. Dec. Oct. Dec. 6, '01 31, '03 18, '03 I 2 3 46.80 45-40 65-39 14-35 31-93 32.29 56.33 55.89 56.25 56.17 15-07 '^ E.D. Nov. Nov. Nov. Nov. 13, '03 31, '03 34, '03 28, '02 I 2 3 2 51.64 55-74 55-38 57-24 39.8S 30.75 29-35 39.89 53-84 54-71 53-31 53.85 53-93 17-31 E.R. Nov. 19, '03 2 56.84 32-55 56.51 56.54 14.70 56.36 14.98 14.99 2l6 BIGELOW Table I. — absolute declinations for 1900.0. uus. minoris 57 b. Date of Obs. No. of Set- tings. Zenith Distance. Declina- Year of Obs. Obs. j Jan. o.o. 1900.0. tion. 1900.0. 45' 1 9' 45 '20' 87-37' W.D. May June 2, '02 13, '02 5 2 47-94 60.13 50-45 50.67 17-65 17.84 Weighted Mean. I {.21 5.97 Mar. 21, '03 4 23. iS 35-43 16.19 '0 W.R. Apr. June 29, '02 8, '02 4 42.91 55-40 46.41 47-13 13-58 14.30 13.99 2-75 > 1 E.D. May May 8, '02 13, '02 3 5 43-53 45-54 44.17 44.61 11-34 11.78 11.97 0-73 Apr. 27, '03 4 30.23 32.01 12.77 E.R. May June 25, '02 26, '02 3 2 53-49 60.34 48.95 48.28 16.12 15-45 15.84 4.60 14-75 3-51 50^ b6' 50 06' W.D. Oct. Oct. 28, '02 30, '02 5 40.73 42.15 37-54 3S-25 10.37 11.08 10.57 0.67 Oct. 31, '02 5 41.67 37-41 10.24 '0 ^ W.R. Jan. Dec. Jan. Jan. 22, '02 18, '02 23, '03 26, '03 2 2 3 I 52.18 55-76 62.29 64.69 34- 1 S 34-67 46.71 4S.77 7.01 7-50 5-95 8.01 7.07 4.17 E.D. Nov. Nov. 21, '02 24, '02 3 5 44.81 45.86 32-93 32.90 5-76 5-73 5-75 5-49 E.R. Nov. 19, '02 4 45.98 34-S3 7.66 7-69 3-55 7-77 3-47 3-49 DECLINATIONS OF CERTAIN NORTH POLAR STARS 217 Table I.— ABSOLUTE DECLIXATIOXS FOR 1900.0 . UKS. \II.\. 33 IIS. Date of Obs. No of Set- tings. Zenith Distance. XJCClltltltlOtl Year of Obs. Obs. 1 Jan. 0.0. 1900.0. 1900.0. 4o°57' 1 40= 58' 83° H' Weight'd Mean. W.D. June June 13, '03 14, '03 5 3 59-64 59.61 50". 8 1 50-51 II. 81 1 1 .5 1 11.67 60.43 W.R. Apr. June 29, '03 8, '03 3 42.06 55-44 47.28 48.04 8.38 9.04 8.72 57.48 0-i May S, '03 2 40-73 43-07 4-07 0 E.D. May 13, '03 3 44.10 44.81 5.SI 5-41 54-17 6 42 Apr. 9, '03 3 25-S5 34-71 6.33 < May 33, '03 I 51-55 49-36 10.36 E.R. May June 35, '03 36, '03 I 3 52.64 60.43 49.49 48.30 10.49 9-30 9-74 58.50 Apr. 27. '03 3 33-S7 37-54 9.06 8.88 57.64 wt. 2. 54^ 28' 54' 38' W.D. Oct. Oct. 38, '03 30, '02 2 3 32^04 32.11 36:87 36.29 15:87 15.39 15-56 55.68 i W.R. Ph > Nov. 24, '02 I 37-83 33-22 12.22 -§ E.D. Feb. 5^ '03 3 57-S3 43-23 II. 71 11.56 59.68 M Feb. 13/03 3 57-72 42-45 10.93 E.R. 57-68 — .10* [57-58] wt. I. [57.62] * Sine f lexure. 2l8 BIGELOW Table I. — absolute declinations for 1900.0. e urs^ MINORIS. Date of Obs. No. of Set- tings. Zenith Distance. Declination 1900.0. Years of Obs. Obs. j Jan. o.o. 1900.0. 39°54' 39' 55' 82° I 3' // " Weighted Mean. W.D. June June 4, 9, '03 '03 I 2 70.24 72.70 63-94 64.62 20.52 21.20 20.90 9.'66 1 W.R. June June s, '03 '03 0 I 70.11 72.20 62.37 62.67 18.95 19.25 19-13 7-S9 i E.D. E.R. May May 8, 22, '02 '02 I 3 59-71 64.79 63.71 64.32 14-75 15-36 15.10 3.S6 May May Apr. 21, 27, '02 '03 '03 I 2 2 68.82 61.15 57.02 68.70 62.47 62.48 19.74 19.05 19.06 19.29 18.60 S.05 7.36 wt. 3 55= 31' 55° 31' W.D. CI Jan. Jan. 8, 23, '02 '03 I I 21.75 29.01 16.43 21.54 5-39 4.96 5:18 6.06 + 2.39* £ W.R. 8.45 0 -^ E.D. E.R. [8.45] wt. I [7-63] * Cos flexure, sine flexure and absolute term. DECLINATIONS OF UKRTAIN NORTH POLAR STAR.S Table I. — absolute declinations for 1900.0. 3 urs^ minoris Date of Obs. No. of Set- tings. Zenith Distance. Year of Obs. Obs. j Jan. o.o. 1900.0. 1900.0. 44° 1 9' 44° 19' 86^36' Weight'd Mean. W.D. June June June June 5/02 9,' 02 4, '03 8, '03 3 5 I 2 66.29 67.62 66.46 68.02 63-13 63.22 62.65 62.80 62.31 62.40 61.46 61.61 62.00 50.76 § W.R. 0 June June 4, '03 8, '03 2 1 63-93 65.14 60.12 59-92 58.93 58.73 58.87 47-63 0 < E.D. June June May 16, '03 17, '02 11, '03 3 3 I 64.06 63.66 53 -78 57-42 56.65 56.99 56.60 55-83 55.80 56.11 44.87 E.R. May Apr. 22, '02 27, '03 I 3 59-27 54-07 60.49 60.65 59-67 59-46 59-59 48.35 59-14 47.90 51° 06' 5i°o6' W.D. Jan. 16, '02 3 34.40 23-74 24.56 24.56 46.6S W.R. Jan. Feb. 32, '03 13^ '02 3 3 24-37 39.61 21.96 21-35 22.78 32.17 22.51 48.73 Below Pol b Mar. Mar. Mar. Feb. 4, '02 5, '02 6, '02 13. '03 3 I I 4 31-65 31-03 31.90 26.43 20.43 19.68 20.42 19.64 21.25 20.50 21.24 20.83 20.97 50.37 E.R. Feb. Feb. Mar. 24. '03 25. '03 2, '03 3 2 I 31.40 31.46 32-58 22.63 22.49 32.92 23.83 23.68 24.1 1 33.88 47-36 22.98 48.26 48.08 220 BIGELOW Table I. — absolute declixatioxs for 1900.0. A urs-e mixoris. Date of 01)S. No. of Set- tings. Zenith Distance. Delination 1900.0. Year of Obs. Ob=. 1 Jan. 0.0. igoo 0. 46= 42' 46 = 42 Weight'd Mean. 8S°59' W.D. Sept. 22, '02 Oct. 7, '02 Oct. S, '02 Oct. 9, '02 3 I 4 3 74-63 75-51 77-83 77-78 43-59 42.90 45-15 45-04 29.66 28.97 31.22 31. II 30-35 19. 1 1 ^ W.R. > 0 Sept. 26, '02 June 8, '03 June 9, '03 2 2 2 73-36 50.22 50-25 41.78 48.44 48.15 27.85 27.69 27.40 27.69 16.45 < E.D. June 26, '02 June 25, '03 2 3 45-31 51-44 3S-3S 44-35 24.45 23.60 24.02 12. 78 E.R. June 25, '03 2 55-06 47-97 27.22 27.26 27-33 16.02 16.09 48= 43' 4S°43' W.D. Feb. 15, '02 Feb. 22, '02 Feb. 24, '02 Mar. 29, '02 Mar. 21, '03 3 7 5 3 3 45-99 47-78 48.60 53-98 44.62 44.18 44.10 44-40 44-99 36.90 58-11 58.03 58-33 58-92 57-65 58!22 13.02 -3 W-R- Mar. 25, '03 3 42.36 34.16 54-91 54-94 16.30 P-( ^ E.D. 0 Mar. 24, '02 Mar. 25, '02 Feb. 6, '03 Ych. 26, '03- I 9 3 3 47-65 47-96. 30.42 35-86 38.88 39-" 31-94 31-91 52.81 53-04 52.69 52.66 52.80 18.44 E.R. Mar. 19, '02 Mar. 27, '02 Feb. 21, '03 Feb. 24, '03 I 3 3 3 49-44 51-08 37-37 37-66 41.30 42.15 34-76 34.26 55.33 56.0S 55-51 55-01 55-51 15-73 55-37 15.87 15.9S DECLINATIONS OF CERTAIN NORTH POLAR STARS 221 Table I. — absolute declinations for 1900.0. cephei 3 hs. Date of Obs. No of Set- tings. Zenith Distance. Year of Obs. Obs. [ Jan. o.o- igoo.o. igoo.o. 43°o6' 43°o5' 84°23' Weight'd Mean. • W.D. J"i^e 5, June 37, '03 '03 3 3 13.41 19.09 13.98 14-15 51-94 53.1 1 53.03 4o'.'78 0 fS W.R. > Oct. iS, Oct. 31, Oct. 34, '03 '03 '03 I I I 48.67 4S.47 48. Si 13.19 11-73 11.86 50-15 49.69 49.83 49-93 38.69 < E.D. June 1 7, Sept. 15, '03 '03 3 0 10,30 38-99 8.40 8.21 46.36 46.17 46.26 35.03 E.R. June 36, '03 I 16.39 11.77 49-73 49-77 3S.53 49-50 38.26 53° 30' 53° 30' W.D. Feb. 33, Mar. 39, '03 '03 3 0 13.74 30.8S 13.07 13.69 35-11 35-73 35-44 35.80 0 '0 W.R. Feb. 15, Apr. 10, '03 '03 '7 3 8.58 19.71 II.OI 11.49 33-05 33-53 33-33 37-91 S E.D. P3 Mar. 4, Mar. 5, '03 '03 1 3 11.03 1 1.09 S.63 8.44 30.67 30.48 30.57 40.67 E.R. Mar. 19, Mar. 8, '03 '03 0 3 17-56 3-88 11.89 0.62 33-93 33-66 33-S2 37-42 33-29 37-95 38.10 22: BIGELOW Table I. — absolute declixatioxs for 1900.0. 76 dracoxis. Date of Obs. No. of Set- tings. Zenith Distance. Year of Obs. Obs. j Jan. o.o. 1900.00. 1900.0. 39° 53' 39° 52' Weight'd Mean. 82°o9' W.D. Sept. Oct. Oct. 26, '02 6, '02 20, '02 3 I I 54-29 56.11 58.95 20.96 20.58 21.03 53-S7 53-49 53-94 53-7S 42-54 (S W.R. Oct. Oct. 10, '01 7, '02 2 I 40.99 53-73 4.78 17.97 51-23 50.88 51. II 39-87 1 E.D. < Oct. Sept. 28, '01 16, '02 2 I 39.80 46.58 1. 00 16.02 47-45 48.93 48.11 36.87 E.R. Oct. Oct. 29, '01 30, '01 2 I 46.45 44.84 7-51 5.78 53-96 52.23 53-23 41.99 51-56 40.32 55° 32 55° 33' W.D. Apr. Apr. II, '02 4. '03 3 73-42 59-48 66.18 52.72 33-27 33-34 33-31 37-93 0 g W.R. Apr. Mar. 10, '02 21, '03 3 I 71-56 54-04 64.36 49-72 31-45 30-34 31.01 40.23 S E.D. 0 Apr. Apr. 7, '03 9. '03 I 2 54-50 55-50 47-31 48.03 27-93 28.65 2S.33 42.91 E.R. Feb. Feb. 5. '03 6, '03 I I 41.69 41.87 50.11 50.00 30.73 30.62 30.71 40.53 30.84 40.40 40.36 DECLINATIONS OF CERTAIN NORTH POLAR STARS 223 Table I. — absolute declinations for 1900.0. cepifei GR. 3548. Date ofObs. No. of Set- tings. Zenith Distance. Declina- Yearof Obs. Obs. 1 Jan. o.o. igoo.o. tion. 1900.0. 44° 20' 44 '20' 86°37' Weighted Mean. W.D. Sept. 22, '03 Oct. 8, '02 5 5 100.38 105.23 69.58 70.14 3S.S8 39-44 39."i6 3 7'.92 6 W.R. Oct. 10, '01 Sept. 26, '02 2 3 86.79 98.42 50.91 66.46 35-56 35-76 35-7^ 24.47 1 E.D. < Oct. 23, '01 Oct. 28, '01 Nov. 21, '02 3 3 3 86.57 87.28 105.40 48.05 47-97 64.51 32.70 32.62 33-81 33-04 21.80 E.R. Oct. 24, '01 Oct. 30, '01 June 26, '02 3 I 3 90-39 91.08 67.97 51-70 51-47 66.76 36-35 36.12 36.06 36.33 24.98 36.03 24.79 51^ 04' 51 '05' W.D. Mar. 29, '02 Apr. II, 'o3 3 3 Si. 79 84.44 78.29 78.76 48.99 49-46 49-23 22.02 6 W.R. Apr. 10, '02 Apr. 15, '02 3 2 81.82 82.50 76.27 76.34 46.97 47.04 47-03 24.31 1 E.D. Mar. 4, '03 Mar. 5, '03 Feb. 13/03 I 3 4 69.97 70.48 49-35 72.85 73.06 57-73 43-55 43-76 43-76 43-71 27-53 E.R. Mar. 19, '03 Mar. 35, '03 Feb. 24/03 2 2 3 77.72 79.60 55-44 76.47 76.95 60.25 47.17 47-65 46.28 47-04 34.20 46.75 24.49 24.64 224 BIGELOW Table I. H. CEPHEI. Dateof Obs. No. of Set- tings. Zenith Distance. Declina- Year of Obs. Obs. } Jan. 0.0. ipoo.o. tion 1500.0. 43 = 19' 43^ '19' Weight'd Mean. 85^36' W.D. Sept. Oct. '03 '03 3 5 94-55 98.30 67-13 67.73 30.60 31-19 30.91 19.67 S W.R. o o o E.D. < Oct. Oct. lO, 24. '01 '03 3 3 81.06 103.4S 46.73 65-32 38.46 28.79 38.67 17-43 Oct. June Sept. 3S, 36, 15, '01 '03 '03 3 2 I 83.21 59-28 S6.33 44-05 61.31 61.36 35.78 24-78 34.83 35.18 13-94 E.R. Oct. June 30. 26, '01 '03 3 2 87.66 63-63 48.05 65.66 39.78 39.13 29-51 18.27 2S.57 17-33 52 =05' 53= 06' W.D. Mar. Apr. Apr. 39, 38, '03 '03 '03 3 3 3 80.36 S3.80 85-31 80.09 79.63 79-45 56.63 56.15 55-98 56^.25 14.99 ^- W.R. Apr. Apr. 10, 24, '03 '03 3 3 8o.3i 82.74 77-23 77.37 53-76 53-90 53-86 17-3S 1 E.D. Mar. Mav Feb. 24, 13, 13. '03 '03 '03 3 4 73-59 81.80 44.33 74-76 74-99 56.46 51.39 51-52 51-25 51-35 19.89 E.R. Mar. Mar. Feb. 19, 31, 31, '03 '03 '03 3 3 3 75-63 76.61 49.09 78.23 78.63 58.73 54-76 55-^6 53-52 54-52 16.72 54.00 17.24 17.29 DECLINATIONS OF CERTAIN NORTH POLAR STARS 225 Table I. — absolute declinations for 1900.0. ^16 II. CEPIIEI. Dateof Obs. No. of Set- tings. Zenith Distance. Declination. 1900.0. Year of Obs. Obs. Jan. o.o. 1900.0. 41 =33' 41 =31' Weigh t'd Mean. 83^48' W.D. Oct. 4, '01 Sept. 22, '02 3 3 43-06 57-57 12.51 32.69 53-24 54-14 53-69 42'.45 . W.R. 6 '0 Oct. 5, '01 Oct. 10, '01 Dec. 6, '01 Oct. 21, '02 Oct. 24, '02 I 3 I I 3 41-51 43-09 55-30 64.62 65.99 io.6i 10.51 10.68 29.99 30.52 51-34 51-24 51.41 51-44 51-97 51-54 40.30 9 E.D. < Oct. 23, '01 Oct. 25, '01 1 0 3 44.6S 44-93 8.07 7.76 48. So 48.49 48. 64 37-40 E.R. Oct. 22, 'oi Oct. 24, '01 Nov. 26, '01 Nov. 30, '01 I 3 I 3 48.85 47.60 55 --4 54.62 12.53 10.71 11.52 10.46 53-26 51-44 52.25 51-19 51.96 40.73 51.46 40.32 53^ d3 53= 54' W.D. Mar. 29, '02 Apr. 28, '02 May 2, '02 I 3 3 52.13 60.65 61.50 53-62 55-51 55-S2 32.17 34-06 34-37 33-67 37.57 1 W.R. Apr. 10, '02 Apr. 15, '02 3 3 53-72 55-00 53.10 52.24 30.65 30.79 30.75 40.49 1 E.D. <—< May 12, '02 May 16, '02 May 17, '02 3 2 3 57.60 57-17 57-95 50.94 50.29 51.02 29.49 2S.84 29.57 29.33 41.92 E.R. Feb. 13, '03 Feb. 24, '03 3 3 20.33 23-49 34-13 33-S3 31-95 31-65 31-83 39.41 31-39 39.85 40.04 226 BIGELOW Table I. — absolute declinations for 1900.0. 39 h. cephei. Date of Obs. No. of Set- tings. Zenith Distance. Year of Obs. Obs. 1 Jan. o.o. 1900.0. tion iqoo.o. 44"= 28' 44 =28' Weighfd Mean. 86°45' W.D. Oct. 4, Dec. II, Sept. 22, '01 '01 '02 3 I 3 S2.65 100.12 96.41 55-14 55-47 75-07 35-27 35 -60 35-33 35-39 24- 15 . W.R. 0 'o Oct. 5, Oct. 7, Dec. 6, '01 '01 '01 2 I 3 80.01 81.27 95-S3 52-13 52.67 51-70 32.26 32.80 31.83 32:28 21.04 0 E.D. Oct. 23, Oct. 25, '01 '01 3 3 83.89 S3-57 49.80 48.84 29-93 28.97 29-45 18.21 < E.R. Oct. 22, Oct. 24, Nov. 9, Nov. 30, Nov. 21, '01 '01 '01 '01 '03 ■-> I 2 I 3 87.12 87.26 93.14 95-37 1 13.36 53-34 52.84 53-" 52.02 72.20 33-47 32.97 33-24 32.15 32.46 32.92 31.68 32.51 21.27 50 =56' 50^ ^s7' W.D. Apr, 1 1 , Apr. 28, May 2, '03 '02 '02 I 3 I 73-35 77-65 77-54 73-31 73-71 72.88 53-05 53-45 52.62 53''o9 18.15 6 W.R. '0 Apr. 10, Apr. 24, '02 '02 3 2 69.70 73-05 69.92 69.91 49.66 49-65 49-69 2 1-55 1 E.D. May 1 2 , May 16, May 24, '02 '02 '02 3 5 2 74-15 74-95 75-18 68.05 68.44 68.10 47-79 48.18 47.84 47-94 23-30 E.R. May 9, May 17, Feb. 6, Feb. 24, '02 '02 '03 '03 3 I 4 4 75.89 77-79 33-10 38-59 70.16 71.18 50-57 50.93 49-90 50.92 50.19 50.55 50.38 20.86 50.27 20.97 21.12 DECLINATIONS OF CERTAIN NORTH POLAR STARS 227 T. VBLE I. Ar.SOLUTE OECLIXATIOXS FOR I 900.0. CEPIIK I 135 IIS. Date of Obs. No. of Set- tings. Zenith Distance- Year of Obs. Obs. Jan. 0.0. rgoo.o. Declination 1900 0. 40°2l' 40^ '21' 82°3S' Weigh t'd Mean. Oct. I, '02 3 80.45 57-76 17-65 W.D. Oct. 6, '02 I 82.78 58.23 18.12 i8ro7 6. S3 Oct. 7? '03 3 83-47 58.55 18.44 *-' Oct. 5i '01 3 60.38 34-28 14.23 6 W.R. Dec. 5i '01 I 77-91 34-79 14-74 14.65 3-41 o 1— 1 iJec. 6, '01 I 78-34 35.08 15-03 > Oct. 38, '01 2 66.04 31.96 I T.9I O E.D. Nov. iS, '01 2 72.33 32.40 12.35 < JNov. 20, '03 3 91-25 52.81 12.70 12-43 1. 19 Nov. 31, '02 3 91-43 52.79 12.68 Oct. 23, '01 2 68.23 36.10 16.05 E.R. Oct. 29, '01 3 71-57 37-17 17.12 16.16 4.93 Nov. 19, '02 3 93-59 55-39 15.28 15-33 4.09 55' '03' 55' '05' Apr. II, '02 2 87-56 88:13 8^24 W.D. Apr. 28, '.02 2 93.01 S9.44 9-55 s!52 2.72 Mar. 21, '03 2 62.70 67.60 7.76 Apr. 10, '02 I 86.40 87.23 7-34 . W.R. Apr. 15, '02 2 87. 20 86.69 6.80 7-30 3-94 'o Mar. 25, '03 2 63.81 67-53 7.69 May 9, '02 I 90.90 85-33 5-44 May 12, '02 I 90.77 84-77 4.88 P5 E.D. May 16, '02 3 91.47 84.96 5-07 5-03 6.21 May 17, '02 I 90.61 84.00 4.11 May 24, '02 3 92.59 85-34 5-45 E.R. Feb. 13, '03 2 51.86 67.76 7.92 8.09 7-23 Mar. 2, '03 2 57.10 68.05 S.21 3-15 4.01 — 4-05 228 BIGELOW Table II. — declixatioxs for 1900.0 from comparisox with zero stars. CEPHEI BR. 256, 6.9 MAG., R.A. 2" l" 25^ Year of 1 Differ- 1 Date. Zero Star. Obs. Jan. 0.0. 1900.0. ential Flexure. 5-K 00 0. 83^05' 83°o5' S3°o5' Oct. 8, ^03 ?. Urs. min. 63-42 2 8'. 94 ! — .13 28'.'8i Mean. Oct. 8, '02 Polaris. 63-65 29.17 -•13 29.04 // W.D. Oct. 28, '02 Polaris. 65.07 30-59 --I3 30-46 29.21 Oct. 28, '02 Gr. 750. 62.64 28.16 — -05 28.11 Oct. 29, '02 Polaris. 64.22 29.74 -.13 29.61 Jan. 22, '02 Gr. 750. 64.97 30.49 -.04 30.45 Jan. 22, '02 5 Urs. min. s.p. 65.28 30.80 1 -.21 30.59 6 Oct. 21, '02 30 H. Camel • s.p. 63-36 28.88 ! — .29 28. 59 3 W.R. Oct. 21, '02 Polaris. 64.23 29.75 I--II 29.64 29.94 Oct. 24, '02 1 H. Draconis s,p. 65.27 30.79 j - .32 30.47 ^ Oct. 24, '02 Polaris. 64.42 29.94 ~~ -^^ 29.83 ^ Jan. 26, '03 Gr. 750. Si. 74 30.02 j - .04 29.98 Nov. 24/02 Polaris. 63-93 29.45 i 4- .11 29.56 E.D. Nov. 24/02 Gr. 750. 62.71 28.23 4- .04 28. 27 29.01 Nov. 28/02 Polaris. 63.58 29.10 4-. II 29.21 Dec. 2, '01 Polaris. 47-35 30.11 4- .12 30.23 E.R. Nov. 19/02 Polaris. 64.86 30.38 i 4- .12 30.50 30.32 Nov. 21/02 Polaris. 65-25 30.77 4- .12 30.89 Nov. 21/02 Gr. 750. 64.11 29.63 4- .04 29.67 June 8, '02 Gr. 750. s.p. 64.05 29-57 -•05 29.52 June 8, '02 Polaris. s.p. 66.91 32-43 -.14 32.29 W.D. Mar. 21/03 X Urs . min . s.p. S3.85 32-13 -.14 31-99 31-44 Mar. 21/03 30 H. Camel. 83.91 32.19 --32 31-S7 Mar. 21/03 Polaris. s.p. 83.40 31.68 - .14 31-54 Apr. 29/02 Polaris. s.p. 64.97 30.49 --13 30-36 W.R. Apr. 29/02 Gr. 750. s.p. 64.97 30.49 — .05 30.44 30-34 6 June 3, '02 Polaris. s.p. 64.65 30.17 --13 30.04 '0 June 3/02 Gr. 750. s.p. 65.07 30.59 - -05 30.54 ^ May 9, '02 Polaris. s.p. 65.10 30.62 4-. 12 30-74 ^ May 9/02 43 n . Cephei s.p. 66.56 32.0S 4- .06 32-14 2 E.D. May 13/02 Polaris. s.p. 64.92 30.44 4- .12 30.56 30.98 May 16, '02 Polaris. s.p. 65-05 30.57 4-. 12 30.69 May 16, '02 43 II. Cejihei s.p. 65.20 30.72 4- .06 30.7S May 25/02 Polaris. s.p. 64.63 30.15 4-. 14 30.29 Feb. 24, '03 Jan. 33, '03 Jan. 33, '03 Feb. 15, '03 Feb. 15, '03 Gr. 750 d Urs. min. Gr. 750 51 H. Cephei s.p. 31.06 31.37 19.01 19.05 57-37 57.68 55-32 55-36 4- .02 -•15 4- .03 — .03 57-39 57-53 55-34 55-34 56.40 c ^ E.D. Nov. 34, '03 Nov. 34, '02 Polaris Gr. 750 33.77 21-55 59.08 + .05 57.86 — .03 59-13 57-S4 [5S.48]* E.R. Nov. 19, '02 Nov. 3 1, '02 Nov. 3 1, '03 Polaris Polaris Gr. 750 30.75 20.96 19.83 57.06 57-27 56.13 4- -05 4- .05 --Q3 57-11 57-32 56.10 56.84 W.D. June 8, '03 Jvine 8, '03 June 1 3, 'o3 June 13, '03 June 14, '03 Polaris Gr. 750 Gr. 750 51 H. Cephei Gr. 750 s.p. s.p. s.p. s.p. s.p. 31.48 18.63 19-13 31.35 19.83 57-79 54-93 55.44 57-56 56.14 -.06 + .03 4- .03 — .03 4- .03 57-73 54-96 55-47 57-54 56-17 56.37 4 W.R. Ph Apr. 39, '03 Apr. 39, '03 June 3, '03 June 3, '03 Gr. 750 Polaris Polaris Gr. 750 s.p. s.p. s.p. s.p. 30.8,- 30.85 30.47 30.S9 57-16 57-16 56.78 57-20 4- -03 --05 — -05 4- .03 57-19 57-" 56-73 57-23 57.06 0^ ^ E.D. May 8, '03 May 8, 'o3 May 13, '03 May 35, 'o3 Gr. 750 e Urs. min. Polaris Gr. 750 s.p. s.p. s.p. 30.37 31.41 21-53 31.14 ^6.68 57-72 57.84 57-45 — .02 4- .23 4- .05 — .02 56.66 57-95 57.89 57-43 57.48 E.R. May 3 1, '03 May 31, '03 , May 33, '03 Gr. 750 e Urs. min. S Urs. min. s.p. 30.15 31.37 30.36 56.46 57-58 56.67 — .02 4- .36 + -17 56-44 57-S4 56.84 57.04 56.S6 * This value wa.s cH.scardeil in obtainins the orifjinal record. tlic final mean. Piobablv there is an eiror in DECLINATIONS OF CERTAIN NORTH POLAR STARS 231 Table II. — declinations for iooo.o from comparison with zero stars. CEPHEI 157 HS., 6.3 MAG., R.A. 4'' 56" iS". Year of Diff. Date. Zero Star. Obs. Jan. 0.0. 1900.0. Flexure. 5—1 )0O.O. 85^49' 85°49' 35' '49' W.D. Feb. 2 3, '03 X Urs. mill. s.p. 5S.'34 4745 — .13 47-33 Mean. Feb. 34, '03 ?. Urs. niin. s.p. 57.55 46.76 — .12 46.64 46!98 Feb. 13, '03 d Urs. min. s.p. 58.01 47.22 -.16 47.06 W.R. Feb. 15, '03 Gr. 750 56.85 46.06 4- .01 46.07 46.40 Feb. 15, '03 51 H. Cepliei 56.89 46.10 --03 46.07 d '0 Mar. 5, '03 d Urs. min. s.p. 57.80 47.01 + -I5 47.16 Ph ]Mar. 5, '03 51 H. Cephei 57-45 46.66 + .03 46.69 0 E.D. Mar. 6, '03 d Urs. min. s.p. 56.34 45-55 4-. 15 45-70 46.31 0 Feb. 5, '03 Polaris 63.66 46.52 1+ .06 46.58 < Feb. 5, '03 Gr. 750 61.57 45-43 — .01 45.42 Feb. 34, '03 5 Urs. min. s.p. 61.90 45-76 4- .17 45-93 Feb. 34, '03 X Urs. min. s.p. 63.80 46.66 + .11 46.77 E.R. Feb. 34, '03 30 H. Camel 62.60 46.46 -.06 46.40 46.01 Feb. 34, '03 Polaris s.p. 61.61 45-47 4- .12 45-59 Feb. 36, '03 5 1 H. Cephei 61.47 45-33 4- .03 45-36 June 9, '02 d Urs. min. 58.01 47.22 -.17 47-05 June 13, '03 Gr. 750 s.p. 55-97 45.18 4- .02 45.20 46.20 W.D. June 13, '03 51 H. Cephei s.p. 58.09 47-30 -.03 47.27 • Alar. 39, '03 Polaris s.p. 61.93 45-79 -.07 45-72 0 '0 Mar.39, '03 Gr. 750 s.p. 61.90 45-76 4- .03 45.78 June 3, '03 Polaris s.p. 56.99 46.20 -.06 46.14 June 3,'o3 Gr. 750 s.p. 57-41 46.62 4- .02 46.64 46.21 W.R. June 5, 'o3 Gr. 750 s.p. 57-19 46.40 4- .02 46.43 Alar. 38, '03 30 H. Camel. 61.67 45-53 _ 32 45-31 Mar. 38, '03 Gr. 750 s.p. 63.64 46.50 4- .02 46.52 June 16, '03 3 Urs. min. 56-97 46.18 4- -17 46.35 F D June 17, '02 d Urs. min. 58.06 47.27 4- .16 47-43 46.92 J_j • 1-^ • June 17, '02 51 H. Cephei s.p. 57.26 46.47 4- .03 46.50 June 17, '02 I H. Draconis^ ' s-P- 58.26 47-47 -.09 47-38 June 24, 'o3 Gr. 750 s.p. 5S.33 47-54 — .01 47-53 46.S3 E.R. June 36, '03 Gr. 750 s.p. 57-53 46.74 — .01 46.73 June 36, '03 51 H. Cephei s.p. 56.99 46.20 4- .03 46.23 46.48 232 BIGELOW Table II. — declinations for 1900.0 from comparison with zero stars. CEPHEI 158 HS., 6.3 MAG., R.A. 5'' 29"" 55'. 1 Year of Diff. Date. Zero Star. Obs. 1900.0 Flexure. 6 — 1900.0 Jan. 00. 85°o8' 85°o8' 85° 08' Jan. 16, '02 5Urs. min. s.p. 57'2i 5 1 ''99 — -19 5i'-So Mean. W.D. Feb. 15, '02 AUrs. min. s.p. 55-" 49.89 --I3 49.76 50:85 Feb. 22, '02 A Urs. min. s.p. 56.34 51.12 -•13 50.99 Jan. 22, '02 rJUrs. min. s.p. 54-96 49-74 --I7 49-57 W.R. Jan. 22, '02 Gr. 750 54-65 49-43 .00 49-43 49-67 Feb. 13, '02 i5Urs. min. s.p. 55-39 50.17 -•17 50.00 Mar. 4, '02 d Urs. min. s.p. 54.68 49.46 + .16 49.62 . E.D. Alar. 5, '02 ^Urs. min. s.p. 56.25 51-03 4-. 16 51-19 50.51 '0 Ph 0 Mar. 5. '02 51 H. Cephei 55-90 50.68 + .04 50.72 Mar. 6, '02 51 H. Cephei 54-22 49.00 + .05 49-05 Feb. 24, '03 5 Urs. min. s.p. 57-73 49-95 4- .19 50.14 ^ Feb. 24, '03 A Urs. min. s.p. 58.63 50.85 4- -13 50.98 Feb. 24^ '03 30 H. Camel. 58.43 50.65 --04 50.61 Feb. 24. '03 Polaris s.p. 57-44 49.66 4-. 14 49.80 E.R. Feb. Feb. 25. '03 25» '03 51 H. Cephei 5 Urs. min. s.p. 56.69 58.16 48.91 50.38 4- .05 4- .19 48.96 50.57 49.91 Feb. 25^ '03 Polaris s.p. 57-51 49-73 4-. 14 49.87 Mar. 2, '03 (5 Urs. min. s.p. 57-75 49-97 + .19 50.16 Mar. 2, '03 51 H. Cephei 56.64 48.86 4- .04 48.90 Mar. 2, '03 I H. Draconis 57.82 50.04 -.07 49-97 Mar. 2, '03 Polaris s.p. 57-59 49.81 i 4- .14 49-95 June 5, '02 '5 Urs. min. 54-97 49-75 1 --19 49-56 W.D. June 9, '02 '5 Urs. min. 56.23 51.01 -.19 50.82 ^0.00 Mar. 29^ '03 Polaris s.p. 57-64 49.S6 -.09 49-77 Mar. 29. '03 Gr. 750 s.p. 57-6i 49-S3 .00 49-83 June 3^ '02 Polaris s.p. 56.52 51-30 — .10 51.20 6 W.R. 0 June Mar. 3» '02 28, '03 Gr. 750 30 H. Camel. s.p. 56-94 51-72 56.90 49.12 — .02 -.24 51-70 48. 88 50.47 Ph 1 Mar. 28, '03 Gr. 750 s.p. 57.87 50.09 .00 50.09 June 16, '02 5 Urs. min. 55.81 50.59 + .18 50.77 •^ E D June 17, '02 '5 Urs. min. 55-S3 50-61 4-. 18 50.79 50.54 x^ • 1^ • June 17, '02 51 H. Cephei s.p. 55-03 49.81 4- -05 49. 86 June 17, '02 I II. Draconis s.p. 56.03 50.81 -.07 50.74 May 21, '02 Gr. 750 s.p. 53-77 4S.55 .00 48.55 E.R. May 21, '02 £ Urs. min. 54.89 49.67 4- .28 49-95 49-59 May 22, '02 5 Urs. min. 55-29 50.07 4- .19 50.26 50.19 DECLINATIONS OF CERTAIN NORTH POLAR STARS 233 Table II. — declixatioxs for 1900.0 from comparison with zero stars. CEPHEI 109 HS., 6.2 MAG., R.A. ^^ 53" 2'. o > o < W.D. W.R. E.D. E.R. W.D. W.R. E.D. E.R. Mar. Mar. Apr. Apr. Feb. Feb. Mar. Mar. Mar. Mar. Mar. Mar. Mar. Mar. June Oct. Oct. Oct. Oct Oct June June June June June Sept. June June 29, 02 29/02 1 1, '02 II, '02 15/02 1 5, '02 21/03 21/03 '02 :>•> 5/02 19, '02 19, '02 27, '02 5/02 6, '02 6, '02 7/02 18, '02 20, '02 9/03 9/03 17/02 17/02 17/02 15/02 26, '02 26, '02 51 H. Cephei A Urs. min. s.p. 76 Draconis s.p. Polaris s.p. Gr. 750 51 H. Cephei 76 Draconis sp. I H. Draconis 8 Urs. min. 8 Urs. min. 51 H. Cephei 51 H. Cephei k Urs. min. X Urs. min. s.p. s.p. s.p. s.p. d Urs. min. 76 Draconis 30 H. Camel, s.p. 76 Draconis I H. Draconis s.p. Polaris 51 H. Cephei s.p. X Urs. min. 8 Urs. min. 51 H. Cephei s.p. I H. Draconis s.p. I H. Draconis s.p. Gr. 750 ^ s.p. 51 H. Cephei s.p. Year of Obs. Jan. 0.0. 84° 20' 30-59 31.02 32-14 30-48 28.98 29.02 21.56 20.63 31.09 30.29 29.94 29.S9 32.14 31-93 32-40 30-53 29. So 31.21 30-65 29.67 22.30 22.69 30.69 29.89 30.89 30.14 29.67 29.13 1900.0. S4°2o' 49.62 50.05 51-17 49-51 48.01 48.05 50.14 49.21 50.12 49-32 48.97 48.92 51-17 50.96 51-43 49.56 48 -S3 50.24 49.68 48. 70 50. 88 51-27 49-72 48.92 49-92 49.17 48.70 48.16 Diff. Flexure. -.06 --I5 -•32 -•15 — .01 --05 -.28 + .05 + .18 + .18 + .06 + .07 + •15 + -I5 --31 + -03 -.27 4- .06 --15 -.06 -.14 4--I9 4- .06 -.06 -.07 4". 02 4- .06 5 — 19000. 84° 20' 49-56 49.90 50-85. 49-36 48.00 48. 00 49.86 49.26 50.30 49-50 49-03 48.99 51-32 51. II 49-97 49-74 48-55 50.S2 51-13 49.91 48.98 49.86 49.10 48.72 48.22 Mean. 49.92 48.78 49.61 50.47 5^-" 49.78 49.25 ^^ ' 4S.86 50.04 49.46 48 -47 49-57 234 BIGELOW Table II. — declinations for 1900.0 from co:mparison with zero stars. URS^ MINORIS 4B, 7.2 MAG., R.A. 7" 58" 3^ Year of Diff. Flexure. Date. Zero Star. Obs. Jan. 0.0. 1900.0. «-i JOO.O. 88°55' 88°55' 88 3- -' Mar. 29, '02 51 H. Cephei 39-54 5942 4- ,04 59-46 Meau. W.D. Mar. 29/02 /iUrs. min. s.p. 39-97 59,85 -,05 59,80 // Mar. 25/03 51 H. Cephei 28,20 58,14 4- ,04 58,18 59-29 Mar, 25/03 Polaris s.p. 29,84 59-7S --05 59-73 Mar. 21/03 76 Draconis s.p. 30.17 60.11 — ,20 59-91 Mar. 21/03 I H, Draconis 29,24 59,18 4--I3 59-31 W.R. Mar. 25/03 k Urs. min. s.p. 29,81 59-75 --05 59-70 59-60 Mar. 25/03 30 H. Camel. 30,04 59-9S 4-. II 60,09 Si Mar. 25/03 Polaris s.p. 29,09 59-03 --05 58.98 '0 0)' Mar, 24/02 51 H. Cephei 38,85 58.73 --03 58,70 Mar. 24/02 / Urs. min. s.p. 38-47 5S.35 + .04 58.39 > 0 Mar. 25/02 A Urs. min, s.jd. 39-44 59-32 4- .04 59-36 ^ E.D. Feb, 5/03 Polaris 29,72 59,66 .00 59-66 59-07 Feb. 5/03 Gr. 750 28.63 58.57 -.07 58,50 Feb. 6/03 51 H. Cephei 29.32 59.26 --03 59-23 Feb. 6/03 y^. Urs. min. s.p. 29.67 59.61 4- .04 .59-65 Feb. 5/03 76 Draconis s.p. 30.71 60.65 4-.21 60,86 Feb. 5/03 I H. Draconis 29-45 59-39 -,i6 59-23 E.R. Feb. 24/03 5 Urs. min. s.p. 29.71 59-65 + ,IO 59-75 {^r\ n T Feb. 24/03 A Urs. min. s.p. 30.61 60.55 4- .04 60,59 \j\j »\j 1 Feb. 24/03 30 H. Camel. 30.41 60.35 --13 60.22 Feb. 24/03 Polaris s.p. 29.42 59-36 + .05 59-41 June 27/02 I H, Draconis s.p. 38.69 5S.57 4-. 18 58.75 58.92 W.D. Sept. 22/02 /iUrs. min. 39.08 58.96 — ,05 58.91 Sept. 26/02 76 Draconis 39-42 59-30 — ,20 59.10 June 27/02 51 H. Cephei s.p. 39-S7 59-75 + .04 59-79 -^ W R June 8/03 X Urs. min. 29.0=; 58.99 -,04 58-95 58.61 0 ^^ •^^" June 8/03 e Urs. min. 28.08 58.02 -,17 57-85 ^ June 8/03 5 Urs. min. 28. 00 57-94 —,09 57-^5 0 June 17/02 i^ Urs. min. 39-17 59-05 4- ,09 59.14 5S.S1 « E.D. June 17/02 51 II. Cephei s.p. 3S.37 58.35 -,04 58.21 June 17/02 I II. Draconis s.p. 39-37 59-25 -,i6 59-09 June 26/02 Gr. 750 s.p. 39.21 59.09 -,09 59.00 June 26/02 51 11. Cephei s.p. 3S.67 58.55 — -05 SS.SO 58.57 E.R. June 25/03 51 11. Cephei s.p. 28. 29 5S'--3 -•05 58.18 June 25/03 I H. Draconis s.p. 28.73 58.67 -.18 58.49 June 25/03 ?. Urs. min. 28,68 58.62 4- .04 58.66 59-" DECLINATIONS OF CERTAIN NORTH POLAR STARS 235 Table II. — declinations for 1900.0 i-kom comparison wiin zejuj stars. CEPHEI 121 HS., 6.3 MAG., R.A. 8" 54" 32'. Year of Diff. Date. Zero Star. Obs. Jan. 0.0. 1900.0. Flexure. 5—1 500.0. 84°34' 84°34' 84^ '34' Feb. 2 3, '03 I Urs. min. s.p. 33.02 59-66 -.15 59-51 Mean. W.D. Mar. 29/02 A Urs. min. s.p. 30.14 57-78 — •15 57-63 58."i4 Mar. 29/02 51 H. Cephei 39.71 57-35 -.06 57-29 Apr. 15/02 30 H. Camel. 32.57 60.21 + •03 60.24 Mar. 25/03 A Urs. min. s.p. 18.39 59-77 -•13 59-64 • W R Mar. 25/03 30 II. Camel, 18.52 60.00 + .03 60.03 59-24 ^ V V . JL\. . Mar. 25/03 Polaris s.p. 17-57 59-05 — 13 58.93 1— 1 Mar. 2S/03 30 H. Camel. 17-39 58.87 + .03 58.90 0 > Mar. 28/03 Gr. 750 s.p. 16.43 57-90 — .21 57-69 0 ^ Mar. 4/02 8 Urs. min. s.p. 29.40 57.04 + •17 57-21 Mar. 5/02 51 H. Cephei 30-15 57-79 + .05 57-S4 E.D. Mar. 5/02 d Urs. min. s.p. 30.50 58-14 + .17 58.31 58.66 Feb. 13/03 Gr. 750 16.78 58.26 + .01 58.37 Feb. 13/03 8 Urs. min. s.p. 17.04 58.52 + .17 58.69 E.R. ISIar. 21/03 Mar. 37/03 I H. Draconis / Urs. min. s.p. 30-75 31-5S 58.39 59.22 -.06 + .14 58.33 59-36 58.84 Sept. 33/03 I Urs. min. 30.86 58.50 -.16 58.34 W.D. Oct. 1/03 I H. Draconis s.p. 33.21 59.85 + .07 59-92 59.31 Oct. 9/o3 I Urs, min. 33.61 60.2 c; — .16 60.09 Oct. 9/03 Polaris 31.01 58.65 -.16 58.49 June 27/02 51 H. Cephei s.p. 31-52 59.16 --05 59-11 Oct. 18/02 I H. Draconis s.p. 30.58 58.22 4- .07 58.39 Oct. 21/02 30 H. Camel, s.p. 30.66 58.30 4- .04 58.34 c8 i^ W.R. Oct. 21/03 Polaris 29-79 57.43 -.14 57-29 ^'-'-^D 6 June 8/03 e Urs. min. 16.41 57.89 -.26 57-63 I June S/03 d Urs. min. 16.33 57.81 -.18 57.63 ^ June 8/03 ). Urs. min. 17.38 5S.86 -•13 58. 73 0 1j June 17/03 0 Urs. min. 30.80 I 58.44 + .19 58.63 M June 17/02 51 H. Cephei s.p. 30.00 57-64 4-. 06 57-70 June 17/02 I H. Draconis s.p. 31.00 58.64 -.06 58.58 58.31 E.D. Sept. 15/02 I H. Draconis s.p. 30.16 57.80 — .06 57-74 Sept. 16/02 76 Draconis 29-99 57-63 + .27 57-90 Nov. 21/02 30 H. Camel s.p. 31.22 SS.86 -•03 58.83 Nov. 21/02 Polaris 3 1 -oo. 58.64 + .14 58.78 E.R. June 26/03 Gr. 750 s.p. 29.81 57-45 4- .02 57-47 57.22 June 36/03 ^i II. Cephei s.p. 39.37 56.91 4- .06 56-97 58.40 236 BIGELOW Table II. declixatioxs for 1900.0 from comparison with zero stars. CAMELOP. S 664, 7.4 MAG., R.A. Il'' 2°" 30\ Year of Difif. Date. Zero Star. Obs. 1900.0. Fle.xure. S — 1900.0. Jan. 0.0. ■ S6° 9' 86° 10' 86^ '10' Mar.2i, '03 A Urs. mill. s.p. 59!58 57^87 — .1 I 57-76 Mean. Mar.2i, '03 Polaris s.p. 60.03 58.32 — .11 5S.21 W.D. Mar.2i, '03 30 H. Camel. 59-52 57.81 + .07 57-88 58^33 Mar. 29, '03 Polaris s.p. 60.75 59-04 — .11 58.93 Mar. 29, '03 Or. 750 s.p. 60.78 59-07 — .30 58.87 Mar.2S, '03 30 H. Camel. 60.70 58.99 + .06 59-05 W.R. Mar. 28, '03 Gr. 750 s-P- 1 59-73 58.02 - .18 57-84 58.09 Mar.31, '03 43 H. Cephei s.p. 59.26 57-55 - -17 57-38 'o Feb. 6, '03 51 II. Cephei i 59-39 57.68 + .02 57-70 ^ E.D. Feb. 6, '03 X Urs. min. s.p.: 59.74 58.03 -f .09 58.12 57-7S > Feb. 26, '03 A Urs. min. s.p. 59.26 57-55 + .09 57-64 o Feb. 26, '03 30 H. Camel. 59-44 57-73 - .06 57-67 Feb. 21, '03 ?. Urs. min. s.p. 59.28 57-57 + .11 57.68 Feb. 21, '03 43 H. Cephei s.p. 59-32 57-61 + .19 57.80 Feb. 25, '03 ' 51 H. Cephei 58.91 57.20 + .03 57.23 Feb. 25, '03 Polaris s.p. 59-73 58.02 + .12 =^8.14 E.R. Feb. 35, '03 0 Urs. iiiiii. s.p. 60. 38 58.67 + -I7 5S.84 57.79 Mar. 2, '03 3 Urs. miii. s.p. 59-55 57.84 + -17 58.01 Mar. 2, '03 51 II. Cephei 58.44 56.73 4- .02 56.75 Mar. 2, '03 I H. Draconis ) 59.62 ; 57.91 - .09 57.82 Mar. 2, '03 Polaris s-P- : 59-39 57-68 + .13 57.S0 58.00 DECLINATIONS OF CERTAIN NORTH I'OLAR STARS 237 Table II. — declixations for 1900.0. i-ko.m comparison' with ;iERO stars. URS. MIN., 3 HS., 6.2 MAG., R.A. 12'' 14" 23'. Year of DiflF. Date. Zero Star. Obs. 1900.0. Flexure. 8— 1900.0. Jan. 0.0. 88^14' 8S°i5' 88° 15' Apr. II , '03 Polaris s.p. 35-39 15:38 — .07 1 5" 2 1 Mean. W.D. Apr. II, '03 Apr. 34, '03 76 Draconis s.p. Polaris s.p. 37-05 35.8S 16.94 15-77 ___ .24 .07 16.70 15-70 16.00 Mar. 3S, '03 Polaris s.p. 16.63 16.46 — .07 16.39 W.R. Apr. 10, '03 76 Draconis s.p. 35-04 H-93 — .21 14.72 Apr. 15, '03 30 H. Camel. 36.43 16.33 4- .10 16.42 15-57 0 May 13, '02 Polaris s.p. 34-oS 13-97 4- .06 14.03 '0 May 33, '03 £ Urs. mill. 35-43 15.32 — .12 15.20 ^ E.D. May 35, '03 Gr. 750 s.p. 35-13 15.02 4- -13 15-15 H-93 0 Feb. 6, '03 51 H. Cephei 15. II 14.95 — .02 14-93 0 Feb. 6, '03 A Urs. min. s.p. 15.46 15-30 4- -05 15-35 ^ Feb. 35, '03 51 H. Cephei 13.98 13.82 — .02 13.80 Feb. 35, '03 Polaris s.p. 14.80 14.64 4- .07 14.71 Feb. 35/03 ^Urs. min. s.p. 43.38 41.16 -.14 41.03 41.27 ^. Mar. 25/03 30 H. Camel. 43.61 41-39 4-.03 41.41 > Mar. 25/03 Polaris s.p. 41.66 40-44 -.14 40.30 < E.D. ^lay 16/03 Polaris s.p. 61.18 40.36 +•15 40.51 May 16/03 43 H. Cephei s.p. 61.03 40.31 + .31 40.43 40.72 May 33/03 £ Urs. min. 61.96 41.14 --03 41. 1 1 Mar. 1/03 Polaris s.p. 41.93 40.70 + •15 40.85 Feb. 6,'o3 76 Draconis s.p. 43-27 42-05 + -33 43.3S Feb. 6,'o3 I H. Draconis 43.30 40.98 -.04 40.94 E.R. Feb. 25/03 51 H. Cephei 43.03 40. So + .08 40. 88 41.67 Feb. 25/03 Polaris s.p. 43.84 41.63 + •17 41.79 Feb. 25/03 c?Urs. min. s.p. 43-49 43.37 + .33 42-49 A-^r. 38/03 Polaris s.p. 43.61 41-39 + •17 41.56 Jan. S/03 Polaris 63.03 41.30 -•17 41.03 W.D. Jan. S/03 £ Urs. min. s .p. 60.77 39-95 + .05 40.00 Oct. S/02 A Urs. min. 63.62 43.80 --17 42.63 41.44 . Oct. 8/02 Polaris 63.09 43.37 -.17 42.10 '0 Oct. 24/03 ill. Draconis s.p. 63.16 41-34 -f.05 41-39 P-I ^ W.R. Oct. Dec. 34/03 18/03 Polaris Polaris 63.01 62.25 43.19 41-43 -.16 -.16 42.03 41.27 41.5S PQ Dec. lS/03 Gr. 750 63.70 41.88 --23 41.65 E.D. Nov. Nov. 13/03 38/03 Polaris Polaris 63.31 61.98 41.49 41.16 + •15 + •^5 41.64 41-31 41.4S E.R. Dec. 3/01 Polaris S0.43 40.03 + -17 40.19 40.60 Nov. 19/03 Polaris 61.64 40.83 + .18 41.00 41. 28 DECLINATIONS OF CERTAIN NORTH POLAR STARS 239 Table II. — declinations eok 1900.0 from comparison with zero stars. 32 II. CAMELOP. SEQ,., 5.5 MAC, 1{.A. I 2'' 48™ 33". Year of Diff. Date. Zero Star. Obs. Jan. 0.0. igoo.o. Flexure. 8—3 900.0. S3°56' 83^^57' 83' '57' Apr. 34, '03 Polaris s.p. 43-58 22.76 -.16 22.60 Mean. W.D. Apr. 38, '03 ]Mar. 39, '03 Polaris Polaris s.p. s.p. 43.28 24.67 23.46 23-43 -.16 -.16 22.30 23.37 22^84 Mar. 39, '03 Gr. 750 s.p. 24.70 23.46 -.25 23.21 June 3, '03 Polaris s.p. 44-74 23-92 -.14 23-78 W.R. June 3, '03 Gr. 750 s.p. 44-32 23-50 — .22 33.28 23-43 June 8,'o3 Polaris s.p. 44.18 23-36 -.14 23.22 May 9, '03 43 H. Cepliei s.p. 42.53 21.71 4-. 21 21.92 E.D. May 9,'o3 Polaris s.p. 43-99 23.17 -f-15 23-32 22.66 6 May 1 3, '03 Polaris s.p. 43.16 22.34 + -I5 22.49 '0 Mar. I, '03 Polaris s.p. 24.00 22.76 + .15 22.91 > May 3 5, '03 Polaris s.p. 44-36 23-54 + -I7 23.71 0 Feb. 24,'o3 8 Urs. min. s.p. 24.21 22.97 -f.22 23.19 < Feb. 34, '03 ^ Urs. niin. s.p. 25.11 23.87 + .16 24-03 Feb. 34, '03 30 H. Camel. 24.91 23.67 — .01 23.66 E.R. Feb. 34, '03 Polaris s.p. 23.92 22.68 + -I7 22.51 23.70 Mar. 2, '03 8 Urs. min. s.p. 25-47 24-23 4-. 22 24-45 Mar. 2/03 51 H. Cephei 24.36 23.12 4-.07 23.19 Mar. 2/03 I H. Draconis 25-54 24.30 -.04 24.26 Mar. 2, '03 Polaris s.p. 25-31 24.07 4--I7 24-24 Apr. 38, '03 Polaris s.p. 24.86 23.62 4--I7 23-79 Oct. 9,'o3 X Urs. min. 45-92 25.10 -•17 24-93 Oct. 9, '03 Polaris 44-32 23-50 — 17 23-33 W.D. Oct. 30, '03 Polaris 44-72 23-90 -•17 23-73 23-94 Oct. 30, '03 Gr. 750 45-43 24.61 — .25 24.36 ^ Oct. 3 1, '02 Polaris 44-32 23-50 -•17 23-33 0 Oct. 7, '03 76 Draconis 45-59 24-77 -.28 24.49 ^ W.R. Oct. 3 1, '03 30 H. Camel. s.p. 45-74 24-92 4- .02 24.94 24-44 0 F D Oct. 21, '02 Polaris 44.87 24.05 -.16 23.89 Nov. 34, '03 Polaris 44.41 23-59 4--15 23-74 34.38 J-J • J-^ • Nov. 24, '02 Gr. 750 45-63 24.81 4-. 22 25-03 E R Nov. 2 1 ,'03 Polaris 43-34 22.52 4-. 18 22.70 ±^ aXV* Nov. 2 1, '02 Gr. 750 44.48 23.66 4-. 26 23.92 23-3^ 23-59 240 BIGELOW Table II. — declinations for 1900.0 from comparison with zero stars. CEPHEI 135 HS., 6.1 MAG., R.A. 13" 45° lO'. Year of Diflf. Date. , Zero Star. Obs. 1900.0 Fle.vure. 6-1 300.0. Jan. 0.0. 83°H' 83°i5' §3= '15' Apr. 28, '03 Polaris S.p. 37''7S 13:82 - .17 1 3. '65 Mean. June 8, '03 Gr. 750 s.p. 41. 38 17.32 - .36 17.06 W.D. June 8, '03 Polaris S.p. 38.43 14.46 - -17 14.29 14:90 Mar. 35, '03 51 II. Ccphei 30.00 14.06 -.08 13.98 Mar. 35, '03 Polaris S.p. 31.64 15-70 --I7 15-53 Apr. 39, '03 Polaris S.p. 39-45 15-49 - -15 15-34 ai W.R. Apr. 39, '03 Gr. 750 S.p. 39-45 15-49 - -23 15.36 15-34 '0 June 3, '03 Polaris s.p. 39-74 15.78 — -15 15-63 June 3, 'o3 Gr. 750 S.p. 39-32 15-36 - -23 15-13 > 0 May 9, '03 Polaris S.p. 38.43 14.46 4- .16 14.62 ^ E.D. May 9, '03 43 II. Cephci S.p. 36.96 13.00 4- .33 13.23 May 13, '03 Polaris S.p. 38.65 14.69 4- :i6 14.85 14.79 May 16, '03 43 II. Cephei S.p. 39-33 15-37 4- -32 15-59 May 16, '02 P(jlaris S.p. 39-4S 15-52 + .16 15.68 May 25, '03 Polaris S.p. 39-39 15-43 4- .18 15.61 E.R. Feb. 35, '03 5 I H. Cephei 19.44 13-50 4- -09 13-59 14.85 Feb. 35, '03 Polaris S.p. 30.76 14.82 4- .18 15.00 Feb. 25, '03 d Urs. niin. s.p. 30.91 14.97 + -23 15.30 Jan. 8, 'o3 Polaris 40.30 16.34 -.19 16.15 Jan. 8, '02 £ Urs. min. s.p. 39-05 15.09 4- .03 15.13 W D Oct. 8, '02 X Urs. min. 40.65 16.69 - -19 16.50 16.36 » T • X-' • Oct. 8, '02 Polaris 40.43 16.46 - -19 16.37 Oct. 9, '02 i Urs. min. 41.70 17-74 - -19 17-55 Oct. 9, '02 Polaris 40.10 16.14 - -19 15.95 Dec. 6, '01 43 II. Cephei 57.37 15.29 --23 15.06 S Dec. 6, '01 Polaris 56.04 14.06 - -17 13.89 £ W.R. Oct. 21, '02 30 II. Camel. s.p. 39-45 ^5-49 4- -01 15-50 14.72 >. Oct. 21, '03 Polaris 38.58 14.62 --17 H-45 1 Dec. 18, '03 Polaris 38.64 14.6S -.17 H-51 Dec. 18, '02 Gr. 750 39-09 15.13 - .34 14.89 Nov. 12, '03 Polaris 39-37 15.41 4- .17 15. 58 N0V.21, '03 30 II. Camel. s.p. 39-40 15.44 .00 15-44 E.D. Nov. 31, '03 Polaris 39- H 15.1S + •17 15-35 15-67 Nov. 34, '03 Polaris 39.38 15-32 4- .17 15.49 Nov. 34, '03 Gr. 750 40.50 16.54 4- .24 16.78 Nov. 28, '03 Polaris 39.16 15.30 4- .17 15-37 E.R. Nov. 19, '03 Polaris 3S-43 14.47 + .19 14.66 14.66 15-15 DECLINATIONS OF CERTAIN NORTH I'OLAR STARS 241 Table II. — declinations fok 1900.0 fkom compakison with zeko stars. URS. MIN. 57 B, 7.1 MAG., R.A. I5" 9'" 2l'. Date. Zero Star. Year of Obs. 1900.0. Diff. Flexure. 5-1 900 0. Jan. 0.0. 87°36' 87°37' . ^^ 01 May 2, '02 30 II. Camel. 38:06 5' 23 + .09 5-32 June 13/02 Gr. 750 s.p. 37.S7 5 04 — -17 4.87 Mean. W.D. June 13/02 Mar. 21/03 51 H. Cephei -^Urs. min. s.p. s.p. 35-75 22.35 3 93 1 1 — .13 .08 3.80 3-03 3'.'78 Mar. 21/03 30 H. Camel. 23.39 3 05 + .10 3- '5 Mar. 21/03 Polaris s.p. 33.80 0 56 — .08 3-48 6 Apr. 29/02 Polaris s.p. 35-87 3 04 — .07 2.97 g W.R. Apr. 29/02 Gr. 750 s.p. 35-S7 3 04 — •15 3.89 3-45 0 June S/02 Polaris s.p. 37-3S 4 55 — .07 4-48 > 0 May S/02 Gr. 750 s.p. 3S.13 5 29 + •15 5-44 < May 8/02 e Urs. min. 37.08 4 25 — .10 4-15 E.D. May 13/02 Polaris s.p. 35-7S 2 95 + .08 3-03 4.41 Apr. 27/03 Gr. 750 s.p. 33.83 4 S8 + -15 4-73 Apr. 27/03 51 H. Cephei s.p. 33.81 4 57 + .11 4.68 ]SIay 25/02 Polaris s.p. 37-78 4 95 + .08 5-03 E.R. June 26/02 Gr. 750 s.p. 37-27 4 44 + •17 4.61 4.92 June 26/02 51 H. Cephei s.p. 37-81 4 98 + •13 5-11 Oct. 2S/02 Polaris 35-H 2 31 .08 2-23 Oct. 2S/02 Gr. 750 37-57 4 74 — .16 4.58 3-37 W.D. Oct. 30/02 Polaris 35-6i 0 78 — .08 3.70 Oct. 30/03 Gr. 750 36-32 3 49 — .16 6-Jo Oct. 31/03 Polan's 36-93 4 10 — .08 4.03 6 Jan. 22/03 Gr. 750 _ 36-44 3 61 — -15 3-46 '0 Jan. 22/02 d Urs. min. s.p. 36-13 0 30 + .03 1 1 -> ^ W.R. Dec. iS/02 Polaris 36.36 3 43 — .08 3-35 3-57 ov\ Dec. 18/02 Gr. 750 36.71 3 88 — -15 3-73 Jan. 26/03 Gr. 750 23-39 4 15 — -15 4.00 Nov. 21/02 30 H. Camel. s.p. 37.33 4 39 — .10 4.29 E.D. Nov. 21/02 Polaris 37.00 4 17 + .07 4-24 3-94 Nov. 34/03 Polaris 35-73 3 90 + .07 2-97 Nov. 24/03 Gr. 750 36-95 4 13 + .14 4.26 E.R. Nov. 19/02 Polaris 36-15 3 32 + .09 3-41 3-41 3.86 242 BIGELOW Table IL — declixatioxs for 1900.0 fkom co.mparisox with zero stars, urs. mix. 33 hs., 7.5 mag., r.a. i ^^ 53™ 47'. Year of Diflf. Date. Zero Star. Obs. Jan. 0.0. 1900.0. Flexure. 8— ic )oo.o. 83°H' 83°H' ^83° 14' June 13/03 Gr. 750 s.p. 38:01 59 -o I -.26 ^8.7-; Mean. W.D. June 13/02 51 H. Cephei s.p. 35-89 56.89 — .21 S6.6S 57-94 June 14/02 Gr. 750 s.p. 37.66 5S.66 -.26 58.40 Apr. 29/02 Polaris s.p. 36.74' 57-74 -•15 57-59 W.R. Apr. 29/02 Gr. 750 s.p. 36.74 57-74 -•23 57-51 58.08 June S/02 Polaris s.p. 38.29 59-29 -•15 59.14 May S/03 Gr. 750 s.p. 37.03 58.02 + -23 58.25 0 May S/02 £ Urs. min. s.p. 35-98 56.9S — .02 56.96 '0 May 13/03 Polaris s.p. 35-98 56.9S 4-. 16 57.14 1^ E.D. Apr. 9/03 76 Draconis s.p. 26.40 57-92 4- .30 58.33 57-94 0 > Apr. 9/03 I H. Draconis 26.77 58.39 — .02 58.27 0 Apr. 9/03 30 H. Camel. 26.80 5S.33 00 58.32 <: Apr. 9/03 Gr. 750 s.p. 26.70 58.33 4-. 23 58.45 May 22/03 d Urs. min. s.p. 37.20 58. 20 4-. 07 58.37 May 25/02 Polaris s.p. 3S.32 59-32 4-. 18 59-50 E.R. June 26/03 Gr. 750 s.p. 37-29 58.29 + .26 58.55 June 26/02 51 H. Cephei s.p. 37-83 58.83 4-. 22 59-05 58.37 Apr. 27/03 £ Urs. min. 26.14 57.66 — .02 57-64 Apr. 27/03 ^Urs. min. 25.60 57-12 4- .07 57-19 Oct. 2S/03 Polaris 35-81 56.81 -.19 56.62 W.D. Oct. 3S/03 Gr. 750 38.24 59-24 -.27 58.97 58.24 Oct. 30/03 Polaris 37-57 58.57 -.19 58.3S Oct. 30/03 Gr. 750 38.28 59-28 -.27 59.01 i W.R. 0 0 Nov. 34/03 Polaris 35-41 S6.41 4-. 17 56.5S Nov. 34/03 Gr. 750 36-63 57-63 4-. 24 57-S7 § E.D. Feb. 5/03 Polaris 24.71 56.23 4-. 17 56.40 57-31 Feb. 5, 03 Gr. 750 2 5. So 57-32 4". 24 '=^7-56 Feb. 13/03 Gr. 750 26.16 57.68 4-. 24 57-92 Feb. 13/03 d Urs. min. s^ ^.p. 25.90 57-42 4-. 08 57-50 E.R. 57.98 DECLINATIONS OF CERTAIN NORTH POLAR STARS 243 Table II. — declinations for 1900.0 from comparison with zepvO stars. CEPHEI 3 US., 7.0 MAG., R.A. 20*" I3'" 59'. c < Date. W.D. W.R. E.D. E.R. W.D. W.R. I E.D. E.R. June June Oct. Oct. Oct. Oct. Oct. June June June Sept. June June 18, 21, 21, 24. 24. 26, 26, Feb. 22, Mar. 29, Mar. 29, Feb. 15, Feb. 15, Apr. 10, Mar. 4, Mar. 5, Mar. 5, Mar. 19, Mar. 19, Mar. 8, 02 02 02 02 02 02 02 02 02 02 02 02 02 02 02 02 02 02 02 02 02 02 02 02 03 •5 Urs. min. I H. Draconis s.p. I H. Draconis s.p. 30 H. Camel, s.p. Polaris I H. Draconis s.p. Polaris d Urs. min. 51 H. Cephei s.p. I H. Draconis s.p. I H. Draconis s.p. Gr. 750^ ^ s.p. 51 H. Cephei s.p. I Urs. min. s.p. A Urs. min. s.p. 51 H. Cephei Gr. 750 51 H. Cephei 76 Draconis s.p. 0 Urs. min. s.p. 51 H. Cephei (5 Urs. min. s.p. A Urs. min. s.p. 51 H. Cephei 1 H. Draconis Year of Obs. Jan. 0.0. S4°2 2' 59-19 61. 2S 60.15 60.35 61.22 61. II 60.26 59.72 60.52 59-92 60.48 60.76 61.30 60.39 60.66 61.09 59-90 59.S6 59.62 60.14 59-93 59.5S 58.77 61.02 70.22 Diff. Flexure. 5 — 1900.0. 84°22' 3 7 '-'15 39-24 38.11 38.31 39.18 39-07 38.22 37.68 38 .48 37.88 38.44 38.72 39.26 38.35 38.62 39-05 37.86 37.82 37-58 38.10 37-89 37-54 3<5.73 38.9S 37-18 •05 -33 .29 .26 .08 .29 .08 .04 •17 .29 .29 .24 .20 — .11 — .11 — .20 — .22 — .18 4- .05 84°22' , Mean. 4- 4- 4- 4- + 4- 4- 4- 4- 4- + 4- •05 •17 •05 .1 1 .19 ■31 37.10 38.91 37.82 38.05 39.10 38.78 38.14 37-72 38.65 38.17 38.73 38.96 39-46 38.24 38.51 38.85 37-64 37-64 37-63 38. 15 38.06 37-59 36.84 39-17 37-49 3S.00 38-38 38. 39.21 J8.53 37-64 37-93 37-83 38.23 244 BIGELOW Table II. — declinations for 1900.0 from comparison with zero stars. CEPHEI gr. 3548, 7.3 :mag., r.a. 31'' 19™ 35% Date. Zero Star. Year of Obs. Jan. 0 0. 1900.0. Diff. Flexure. S — 1900.0. 86°37' 86°37' 86 ^37' W.D. Sept. 33/03 Oct. 8/03 Oct. S/03 A Urs. min. A Urs. min. Polaris 55-35 54-35 54-5S 34.65 33.65 33.88 --05 --05 -•05 34.60 23.60 23 -S3 Mean. 34.01 i W.R. 0 Ph Oct. 10/01 Sept. 26/03 76 Draconis A Urs. min. 39-34 54-04 23-99 23-34 4- .08 — •05 34.07 23-29 23-68 i 1 E.D. < Oct. 23/01 Oct. 28/01 Nov. 31/02 Nov. 3l/03 30 H. Camel. 76 Draconis 30 H. Camel. Polaris s.p. s.p. 39-36 40.18 54-36 54-5S 34.01 34.83 33.66 33.88 + .31 -.08 4-. 31 + .04 34.33 24-75 23-S7 23-92 34.19 E.R. Oct. 30/01 June 26/02 June 26/03 76 Draconis Gr. 750 51 H. Cephei s.p. s.p. 38.90 55-75 56.39 23-55 35.05 25-59 -.09 + .19 + -I5 23-46 2S.24 25-74 34.81 W.D. Mar. 29/03 Mar. 39/03 Apr. 1 1/03 Apr. 1 1/03 51 H. Cephei X Urs. min. 76 Draconis Polaris s.p. s.p. s.p. 56.49 56.06 54-17 55-83 25-79 25-36 23-47 25-13 — .IS -.06 4-. II -.06 25.64 35.30 23-58 35.07 34.90 W.R. Apr. 10/03 Apr. I '^/o3 76 Draconis 30 H. Camel. s.p. 54-S4 53-OI 34.14 33.31 -f .10 — .31 24-24 33.10 33.17 Below Pole. b Mar. 4/03 Mar. 5/03 Mar. 5/03 Feb. 13/03 Feb. 13/03 8 Urs. min. d Urs. min. 5 I H. Cephei Gr. 750 t?Urs. min. s.p. s.p. s.p. 55-92 54-96 55-31 70.88 70.62 35.33 34.36 34.61 34.85 24-59 00 00 4-. 13 +.16 00 25.22 34.36 24-73 25.01 24-59 34.76 E.R. jSIar. 19/03 Jvlar. 19/03 Feb. 34/03 Feb. 34/03 Feb. 34/03 Feb. 34/03 51 II. Cephei A Urs. min. oUrs. min. / Urs. min. 30 11. Camel. Polaris s.p. s.p. s.p. s.p. 56.44 54-19 71.09 70.19 70.39 71-3S 25-74 23-49 35.06 34.16 24-36 25-35 +.14 4- .06 00 4- .06 + •23 4- .05 35.88 23-55 35.06 34.33 24-59 35.40 34.78 34.38 DECLINATIONS OF CERTAIN NORTH POLAR STARS 245 Table II. — Declinations for 1900.0 from comi'aiuson with zero stars. 32 II. CEPHEI, 5.3 MAG., R.A. 33" 3l"' iS". Date. Zero Star. Year of Obs. 1900.0. Diff. Flexure..^ 6 — 19000. Jan. 0.0. 85^36' ti S5°36' M '36' Mean. W D ^^P^' '03 ). Urs. min. 53.90 16:37 — .07 16:30 i6."54 V V • J_^ • Oct. I, '03 I H. Draconis s p- 53- 61 17.08 — •30 16.78 Oct. lO, '01 76 Draconis 35- 16 16.89 4- .06 16.95 6 W.R. Oct. 24. '03 I H. Draconis s p- 54 57 18.04 — .37 17.77 17. 28 ^ ^ Oct. 24. '03 Polaris 53 73 17.19 — .06 17-13 > Oct. 3S, '01 76 Draconis 36 36 17.99 — .07 17.93 o E.D. June 26, '03 \ Urs. min. 52 29 15.76 4- .06 15.83 17.04 ^ Sept 15. '03 I H. Draconis s .p. 53 63 17.10 4- .37 17-37 Oct. 30^ '01 76 Draconis 35 48 17.21 — .07 17.14 E.R. June 26, '03 Gr. 750 s .p. 54 65 18.12 + .31 18.33 18.10 June 26, '03 51 H. Cephei s .p. 55 19 18.66 4- •17 18.83 Mar. 39, '03 51 H. Cephei 54 69 1S.16 — -17 17.99 Mar. 39, '03 /Urs. min. s .p. 54 36 17-73 — .08 17.65 W.D. Apr. II, '03 76 Draconis s .p. 53 31 16.78 4- .09 16.87 17.91 Apr. II, '03 Polaris s .p. 54 97 18.44 — .08 18.36 Apr. 38, '03 Polaris s .p. 55 28 18.75 — .08 18.67 . W.R. Apr. 10, '03 76 Draconis s .p. 53 88 17-35 4- .08 17-43 17-30 Apr. 24, '03 I H. Draconis 53 94 17.41 — •25 17.16 1— t Mar. 24, '03 / Urs. min. s .p. 53 71 17.18 + .07 17.25 E D Mar. 24, '02 51 H. Cephei 53 33 16.80 4- .14 16.94 17.22 Ij z*^ 1 Feb. i3r '03 Gr. 750 73 15 17.36 4- .19 17-55 Feb. 13. '03 5 Urs. min. s .p. 71 89 17.10 4- -03 17-13 Mar. 19, '03 51 H. Cephei 54 6'S> 18.15 4- .16 18.31 Mar. 19, '03 >iUrs. min. s .p. 52 43 15.90 + .08 iv9S E.R. Mar. 31, '03 I H. Draconis 52 80 16.37 4- .38 16.55 17.14 Feb. 31, '03 43 H. Cephei s .p. 72 •17 17-38 .00 17-38 Feb. 31, '03 A Urs. min. s .p. 73 .21 17.43 4- .08 17-50 / 17.33 Proc. Wash. Acad. Sci., July, 1905. 246 BIGELOW Table II. — declixatioxs for 1900.0 from comparisox with zero stars. 36 H. CEPHEI, 5.7 ]MAG., R.A. 33*' 55™ 13% ; Year of ! Diff. Date. Zero Star. Obs. 1900.0. Flexure. 6—1 900.0. Jan. 0.0. 83°48' 83^48' 83°4S' ii II Mean. W.D. Oct. 4, '01 30 H. Camel, s.p. 59-23 39-96 -30 39-66 39-73 Sept. 23, '02 A Urs. min. 78.46 39-91 — .11 39-80 Oct. 5, '01 30 H. Camel, s.p. 59-35 40.08 — .37 39-81 Oct. 10, '01 76 Draconis 58-94 39-67 + -03 39-70 Dec. 6, '01 43 H. Cephei 59.06 39-79 — -03 39-76 0 W.R. 0 Dec. 6, '01 Oct. 21, '03 Polaris 30 H. Camel, s.p. 60.39 7S.61 41 .03 40.06 ~~' .09 .37 40.93 39-79 40.25 ^ Oct. 21, '03 Polaris 79-4S 1 40.93 — .09 40. 84 0 > Oct. 34, '03 I H. Draconis s.p. 79-77 41.33 — •30 40.92 0 < E.D. Oct. 34, '03 i Polaris 78.93 40-37 — .09 40.28 Oct. 33, '01 30 H. Camel, s.p. 59-38 40.1 1 + .37 40-38 39-80 Oct. 35, '01 30 H. Camel, s.p. 58.33 38.95 4- .37 39.33 Oct. 33, '01 43 H. Cephei 61.33 41.96 4- .04 43.00 E.R. Nov. 36, '01 43 H. Cephei 60.77 41.50 4- .04 41-54 41-34 Nov. 30, '01 30 H. Camel, s.p. 59-44 40.17 4- -31 40. 48 Mar. 39, '02 51 H. Cephei St. 16 43.61 .31 43.40 W.D. Mar. 39, '03 Apr. 38, '03 A Urs. min. s.p. Polaris s.p. So.73 79.23 43. iS 40.67 — .13 .13 42.06 40.55 40.70 May 2, '02 30 H. Camel. 76.60 38.05 — .37 37-78 0 W.R. '0 Apr. 10, '02 76 Draconis s.p. 79.01 40.46 i + .04 40. so. 39-40 Apr. 15, '03 30 H. Camel. 77.11 38.56 - .37 38.39 Ph > F D May 16, '02 43 II. Cephei s.p. 7S.6S 40.13 ' + .04 40.17 40.13 0^ May 16, '02 Polaris s.p. 78.53 39-98 \ 4- .10 40. oS 0 Feb. 13, '03 51 II. Cephei 97.64 39.83 ! 4- .31 40.03 Feb. 24, '03 d Urs. min. s.p. 97-5^ 1 39-69 4- .07 39-76 E.R. Feb. 24, '03 X Urs. min. s.p. 96.61 38.79 4- •13 38.93 39.62 Feb. 34, '03 30 II. Camel. 96. Si 38.99 4- •30 39-39 Feb. 34, '03 Polaris s.p. 9 7. So 1 •^9.08 4- .12 40.10 0 J J < 40.12 DECLINATIONS OF CERTAIN NORTH POLAR STARS 247 Table II. — declinations for 1900.0 from comparison with zero stars. 39 H. CEPHEI, 5.9 MAG., R.A. 23". 27™ 49'. Year of D ft Date. Zero Star. Obs. Jan. 0.0. 1900.0. Flex ure. 6-1 900.0. 86=45' S6°45' 86' 4:) Oet. 4, '01 30 11. Camel. s.p. 41". 86 3i'.'99 — .24 31.75 Mean. W.D. Dec. II, '01 43 H. Cephei 41-37 21.50 4- .02 31.53 31.44 Sept. 3 3, '03 A Urs. mill. 60.84 31. 10 — -05 21.05 Oct. 5, '01 30 H. Camel. s.p. 40.87 3 1. 00 — .22 20.78 W.R. Oct. 7, '01 30 H. Camel. s.p. 40.99 31.12 — .22 20.90 30.83 6 Dec. 6, '01 43 H. Cephei 40.08 20.21 4- .03 20.23 I Dec. 6, '01 Polaris 41-31 21.44 — .04 21.40 0 S E.D. 5 Oct. 23, '01 ! 30 H. Camel. s.p. 41. II 21.24 4- .21 21-45 30.54 Oct. 35, '01 30 n. Camel. s.p. 39-30 19-43 + .31 19.64 61.40 21.66 — .22 21.44 -1 . «,U A May 16, '02 43 PI. Cephei s.p. 60.53 20.79 — .02 20.77 § E.D. May 16, '02 Polaris s.p. 60.38 20.64 4- .04 20.68 30,67 May 24, '02 Polaris s.p. 60.36 20.52 4- .04^ 20.56 P5 May 9, '02 Polaris s.p. 60.68 20.94 4- •05 20.99 Feb. 6, '03 76 Draconis s.p. 79.71 20.09 — .1 I 19.98 Feb. 6, '03 I H. Draconis 80.78 21.16 4- .26 21.42 E.R. Feb. 24, '03 d Urs. min. s.p. 80.41 20.79 00 20.79 30.65 Feb. 24, '03 / Urs. min. s.p. 79-51 19.89 + .06 19-95 Feb. 24, '03 30 PI. Camel. 79.71 20.09 4- •23 20.32 Feb. 24, '03 Polaris s.p. 80.70 21.0S 4- •05 21.13 20.99 248 BIGELOW Table II. — declination for 1900.0 from comparison with zero stars. CEPHEI 135 HS., 6.3 MAG., R.A. 23'' 51"" 46'. Date. Zero Star. Year of Obs. 1900.0. Diff. Flexure. &— 900.0. Jan. 0.0. 83°38' 82^38' 83 °3S' Oct. I,'03 I H. Draconis s.p. 43-65 3-54 -•37 3-17 Mean. Oct. 6,'03 76 Draconis 44-40 4 29 4- .01 4-30 W.D. Oct. 6,'02 30 H. Camel, s.p. 45-13 5 03 --33 4.69 4-32 Oct. 7,'03 J Urs. mill. 45.01 4 90 — -15 4-75 Oct. 7,'03 Polaris 44-93 4 82 -.14 4.68 Oct. 5, '01 30 H. Camel, s.p. 33.03 --> 97 — .39 3.68 6 -o W.R. Ph Dec. 5, '01 43 H. Cephei 23.30 3 15 — .05 3.10 3-42 Dec. 6/01 43 H. Cephei 33.46 0 41 -•05 3-36 0 > Dec. 6, '01 Polaris 34.69 4 64 — .11 4-53 0 E.D. Oct. 3S,'0I 76 Draconis 34.17 4 13 — .01 4. II Nov. iS,'oi 43 H. Cephei 35.01 4 96 4- .06 5.03 1 'TO Nov. 3I,'03 30 H. Camel, s.p. 43.64 3 53 4- .29 2.83 0- /'^ Nov. 3 I, '03 Polaris 43. 86 3 75 4- .13 3.87 Oct. 3 3, '01 43 H. Cephei 34. So 4 75 4- .06 4.81 E.R. Oct. 39/01 76 Draconis 22.73 3 6S — .01 3.67 3-97 Nov. 19/02 Polaris 44.41 4 30 + -13 4-43 Apr. I I,'03 76 Draconis s.p. 44.80 4 69 4- .03 4.71 Apr. 1 I, '03 Polaris s.p. 46.46 6 35 — -15 6. 30 W.D. Apr. 3S,'03 Polaris s.p. 45.39 5 iS --15 5-03 5-15 Mar. 31/03 A Urs. mill. s.p. 65.48 5 32 — -15 5-17 Mar. 31/03 30 H. Camel. 65-54 5 3S -•33 5^05 Mar. 31/03 Polaris s.p. 65-03 4 S7 — -15 4.73 Apr. 10/03 76 Draconis s.p. 43.S8 3 77 + .01 3-7S Apr. 15/03 30 II. Camel. 43.66 3 55 --30 3.25 i W.R. Mar. 25/03 / Urs. mill. s.p. 63. Si 1 65 -.14 2.51 3.7S 0 Ph Mar. 25/03 30 II. Camel. 63. 58 3 42 -•30 2.13 ^ 0 Mar. 25/03 Polaris s.p. 63-53 3 37 -.14 May 9/02 Polaris s.p. 43-H 3 03 + •13 3.16 May 9/03 43 II. Cephei s.p. 44.60 4 49 4- .07 4.56 E.D. May 16/03 43 H. Cephei s.p. 44.01 3 90 4- .07 3-97 3-72 May 16/03 Polaris s.p. 43.S6 3 75 + -13 3.SS May 34/03 Polaris s.p. 43.03 2 91 + •13 3-04 Feb. 13/03 51 II. Cephei 64.01 3 85 4- .34 4-09 Mar. 2/03 fJUrs. mill. s.p. 63-58 3 42 4-. 10 3-52 E.R. Mar. 2/03 51 II. Cephei 64.69 4 53 + .25 4.78 3-96 ISIar. 2/03 I II. Draconis 63-51 3 35 + •35 3-70 Mar. 2/03 Polaris s.p. 63-74 T. cS 4- .IS 3-73 0 >' 1 ^' 3.88 DECLINATIONS OF CERTAIN NORTH POLAR STARS 249 Table III. — observed declinations for 1900.0 compared with CATALOGUE PLACES. Declinations. Observed B. T. for Right Asceusion. Newcomb's Funda- Berliner Jarbuch for igoo. Name. Fr. Com- Igoo with Correc- Absolute. parison with Zero mental Catalogue. tions, Reduced Stars. to igoo.o. h m s 0 / // // ^^ ^^ 43 H. Cephei 0 55 I 85 43 14-55 14.74 14.82 14.53 Polaris I 0 ^ 33 88 46 36.64 36.61 36.63 26.50 Cephei, Br. 356 3 I 25 83 5 30-44 30.33 Cephei 147 Hs. 3 8 35 84 33 [26.87] 36.59 Cephei 149 Hs. 3 33 55 Z6 19 [56.87] 56.S6 Gr. 7 so 4 5 5 85 17 38.73 38.18 38.81 Cephei 1^7 Hs. 4 56 18 85 49 46-34 46.48 Cephei 158 Hs. 5 39 55 85 8 49-92 50.19 49.60 51 H. Cephei 6 53 45:87 13 30.57 20.53 20.15 20.05 Cephei 109 Hs. 7 53 3 84 30 49.76 49-57 Urs. min. 4B. 7 58 3 88 55 59.39 59-11 59-36 Ceph. 131 Hs. 8 54 32 84 34 58.33 58.40 I H. Dr aeon is 9 33 SI Si 46 6.98 6.91 6.99 6.73 30 H. Camel. 10 18 55 83 4 3.80 3.78 3-32 3.38 Camel., s 664 1 1 3 30 86 10 [57.78] 58.00 Urs. min. 3 Hs. 13 14 23 88 15 14.74 14.85 15.30 33 H. Camel, pr. 13 48 16 83 51 41.03 41.38 33 H. Camel, seq. 13 48 23 '83 57 23-31 23-59 23-39 Ceph. 135 Hs. 13 45 10 83 15 14.99 15. H Urs. min. 57B 15 9 31 87 37 3-49 3-86 4-04 Urs. min. 33 Hs. 15 53 47 83 14 [57-62] 57.98 £ Urs. min. 16 56 13 83 13 [7-63] 7.68 7.66 7.S5 ^ Urs. mi7z. 18 4 33 86 36 48.08 47.71 47-52 48.13 ). Urs. min. 19 33 30 88 59 15.98 15.81 15-43 15-94 Cephei 3 Hs. 30 13 59 84 33 38.10 38-23 76 Draconis 30 49 51 83 9 40.36 40.01 39.66 40.33 Ceph., Gr. 3548 31 19 35 86 37 34.64 34.38 34.85 33 H. Cephei 33 31 18 85 36 17.39 17.33 36 H. Cephei 23 55 13 183 48 40.04 40.13 39 H. Cephei 0 1 ^0 37 49 86 45 31.13 30.99 31.14 Ceph. 135 Hs. 23 51 46 83 38 4.05 3.8S PROCEEDINGS OF THE WASHINGTON ACADEMY OF SCIENCES Vol. VII, pp. 251-256. July 24, 1905, THE CAMBRIAN FAUNA OF INDIA. By Charles D. Walcott. Through the courtesy of the Director of the Geological Sur- ve}^ of India, I have had the opportunity of studying the collec- tions of Cambrian fossils from the Cambrian rocks of the Salt Range. The fauna was first described by Dr. William Waagen ^ and later by Dr. K. Redlich." In order to have a stratigraphic section to which the subfaunas may be referred, the following is made up from Dr. Fritz Noetling's^ sections and Dr. Red- lich's* statements of the occurrence of the fossils. Dr. Noet- ling's detailed sections ^ give the stratigraphic succession and character of the Cambrian shales and sandstones, and prove that the sediments of the eastern section of the Salt Range were deposited mainly near shore. The fossils show that they w^ere subjected to the vicissitudes of life on a shifting, sandy and muddy bottom. Ag-e 0/ the Contained Fauna. — The first reference of the brachiopods of the lower strata of the Salt Range was to the Silurian." Subsequently they were referred by Dr. Waagen to iMem. Geol. Sur. India, Ser. XIII, Vol. I, pp. 748-770, 18S5 ; Vol. IV, pp. S9-108, 1891. 2 Mem. Geol. Sur. India, New Ser., Vol. I, pp. 1-13, 1899. 3 Records Geol. Sur. India, Vol. XXVII, 1S94, pp. 74-86. Geol. Salt Range, N. Jahr. Mem. Geol. and Pal., 1901, Bd. XIV, p. 416. * Loc. cii., p. 9. sRec. Geol. Sur. India, Vol. XXVII, 1S94, pp. 74-86. ^Mr. Wynne, Geol. Salt Range in the Punjab, Mem. Geol. Sur. India, Vol. XIV, p. 86. Proc. Wash. Acad. Sci., July, 1905. 251 1^2 WALCOTT Baganwalla No fossils found. group Jutana c. Upper magnesian lime- 180 Psendotheca -vaaffeni. 1 1 group stone. b. Middle magnesian limestone. a. Lower magnesian lime- stone. Thickness about i8o feet. Ptyclioparia richteri. Lingulella fucksi. ; V Dark compact shaly thin- 15-1S Redlichia ncetlingi. bedded and subconcretion- ary, micaceous but not glau- Hxolifhes. conitic. Obolus ( Liiigulella ) 1 i Kussak Thickness 15-18 feet. fusc//t, 0. ( LingulcUa ) zvaftniecki, Acrothele [Mobergia) granulata. IV Thin - bedded purple, 15 Disciiiolcpis granulata. group sandy and micaceous shales. Thickness approximately 15 feet. SckizQpholis rngosa , Ncobolus 'carthi, Lakh- intjta li?iguloides, Obolus {Lingulella) kiurensis. Cambrian III Upper Annelid sandstone. 40 Ptchofaria ? vjarf/ii. A series of hard cream- P.? i>idicus JVa age u , colored sandstones, flaggy Hvolifhcs zvynnei, Hvo- and glauconitic, alternating lithes kussakcnsts, Wyn- with soft, dark and shaly nia -u.' art hi. layers. Thickness about 40 feet. II Dark purple shales with 10 Hyolithes -wynnei, and green patches. fragments of undeter- ' Thickness about 10 feet. mined trilobite. I Lower Annelid sandstone. 50 Annelid trails and frag- A series of hard cream- ments of brachiopods and colored sandstones, alter- Hyolithes. nating with darker shaly partings or soft sandy beds. Thickness about 50 feet. Khewra Purple sandstones. 200 No fossils found. group 200-400 feet thick. to 400 Pre- Salt marls. 1 Cambrian 1 the Carboniferous fauna.' On the discovery of Cambrian trilo- bites Dr. Waagen referred the fauna to the Cambrian,- and ten- tatively conchided that the Olenus, Paradoxides and OleneHus ' Loc. cit., 1885. "^ Loc. cit., 1891, p. 94. THE CAMBRIAN FAUNA OF INDIA 253 faunas might be represented.' Later (1899) Dr. K. Redlich described the collections made by Messrs. Middlemiss and Noetling, and concluded that the Cambrian fauna of the Salt range cannot be referred to a later horizon than the Paradoxides zone^. My review of the type material received from Dr. Hol- land and a small collection made for me by Dr. Fritz Noetling lead me to agree with Dr. Redlich and also to add that there is no evidence that the fauna is much older than the Paradoxides or Middle Cambrian fauna. The supposed heads of Olcnellus mentioned by Dr. Waagen are very properly referred by Dr. Redlich to a new genus named by him Hocfcria which name being preoccupied was replaced by Redlichia b}^ Cossman.^ This genus differs from Olcnelhis " by the presence of a well-developed facial suture and by the distinct separation of the eyes from the glabella." ^ Another difference is the absence of the characteristic surface sculpture of OloicIInsJ' My present impression is that Redlichia is a direct descendant of Olenelhis and that it lived in late Lower Cambrian or Middle Cambrian time. Dr. Redlich calls attention to the resemblance between Red- lichia^ and Protolemts Matthew, but he does not note the re- semblance to Zacanthoides Walcott.*' Both Protolenus and Zacanthoidcs are Middle Cambrian genera. The former occurs just below the Paradoxides fauna on Handford Brook, New Brunswick, and the Olenellus fauna is found 460 to 480 feet ' Loc. ct'L, p. 106. 'Mem. Geol. Sur. India, N. Ser., Vol. i, 1899, p. 11. * Revue Cretique Paleozoologie, Sixieme Ann., 1902, p. 52. * Loc. cit., p. 2. 5 Dr. Redlich states that Walcott mentions the presence of facial suture in Oletiellus and quotes from page 175 of Bulletin 30, U. S. Geol. Survey, 1886. In 1S91 I wrote of the supposed suture in Olenellus: "The discovery of more perfect specimens of O. (M.) asafhoides shows that what I had identified as the facial suture is a raised line in the coat of the interior of the shell that fills a de- pressed line occupying the position of the suture. I have since found this line in many specimens but in none is there a true suture cutting through the shell, as in Paradoxides and most other genera of trilobites." (Tenth Ann. Rep. U. S. Geol. Sur., 1891, pp. 633, 634). ^ As shown on plate XXV, figures 2, 3, 4 and 6, Bulletin 30, U. S. Geol. Surv., 1S86. 254 WALCOTT beneath in the same section.^ In western Utah, in the House range, the Middle Cambrian contains over 400 feet of strata and is characterized by four subfaunas of which Zacanthoides is the oldest.^ To the westward in Nevada, the Olenellus fauna ranges through 5,000 feet of beds, and the Upper Cambrian fauna is found 1,500 feet above the Middle Cambrian fauna in the Highland range.' By reference to the table showing the Cambrian formations of the Salt Range and contained fossils {ante, p. 252) it will be noted that there are only 115 feet of fossiliferous strata beneath the beds containing Redlichia ncetlingi and the basal sandstone. In the absence of any fossils clearly indicating the Olenellus fauna I think it is unwise at present to assume any other age for the fossiliferous Cambrian beds than Middle Cambrian. The brachiopods of division IV, Neobolus beds, of the Khus- sak group, indicate a stage of evolution in advance of any brachiopod we know in the Olenellus fauna. LahJnnina lin- guloi'des with its interior platforms and perforate ventral valve and Neobolus xuartJii with its central platform in the ventral valve indicate Ordovician rather than Lower Cambrian development. Notes on the Fossils. — The annelid trails are of the usual forms occurring on the surface and penetrating the sandy layers. Dr. Redlich illustrates a form of Cylindritcs, and states that many worm-trails remain alike from the Cambrian to the pres- ent day. ^ jBrachiopoda : Oholus {^Lini^ulcllii) wannieeki Redlich and O. {L,.) k fur en sis Waagen, are essentially Middle Cambrian forms and O. {L.) fuchsi suggests the Upper Cambrian, Lini^iilefis- like shells. Aerothele {Alobergid) o-rantilata Redlich is not unlike Aerothele suhsidua White, which is abundant in the Middle Cambrian of Utah. The brachiopods, Discinolefis granulata Waagen, Schizopholus rugosa Waagen, Neobolus ' Lower Cambrian terrane in the Atlantic Province, Proc. Washington Acad. Sci., Vol. I, pp. 320-322. * This section was examined in 1903. I expect to study it more in detail this season (1905) as it is the most complete section of the IMitldle Camhrian zone known to me in America. 3 Bull. 30, U. S. Geol. Surv., pp. 33-35. * Loc. cit., p. 8, pi. I, figs. 19 and 20, THE CAMBRIAN FAUNA OK INDIA =55 zvarlhi Waagen and Lakliniina liiigiiloidcii Waagen all indicate a stage of development more advanced than that of the brachi- opods of the Cambrian faunas in other parts of the world. Wynnia zuarthi Waagen is the onl}'- articulate brachiopod in the collection ; it is related to both Nisusia and DillitigscUa of the Lower and Middle Cambrian faunas. Plcropoda : The fragments representing Hyolilhcs Jciissahcn- sis Waagen is undistinguishable from young shells of Hyolilhcs ■priinordialis Hall and H. americanus Billings. A similar, if not identical, species occurs with Rcdltchia [Ilceferta) ncetlingt in Division V. Hyolilhcs wynnci Waagen is clearly distin- guished by the median furrow on the ventral side from other spe- cies of the genus. It occurs in Divisions II and III. Pseudo- theca ivaagcui Redlich is one of the doubtful forms which has little stratigraphic value. Its relations appear to be with Stcno- theca. Trilobita: Reference has already been made to Rcdlichia ncellingi Redlich when speaking of the stratigraphic position of the genus. The genus occurs in China in the basal fossilif- erous beds, but it is not far below the characteristic Middle Cambrian fauna. As has been stated, I regard the genus as of late Lower Cambrian or early Middle Cambrian age. Ptycho- ■paria richtcri Redlich from the Magnesian limestone series is a form that might well occur at any horizon of the Cambrian although it is more of a Middle Cambrian type. The same may be said of Ply chof aria zvarlhi from Division III. A frag- ment of the central portions of the head of a trilobite from Divi- sion III, was named Olcnns indices by Waagen. The pustulose surface and strong, rounded glabella indicate a species more nearly related to Conocoryfhc trilincatus Emmons of the Lower Cambrian fauna than Olenus of the Upper Cambrian fauna. The fragment is hardly sufficient to base a generic or specific determination upon. The stratigraphic horizon of this species is in doubt. It probably came from Division IV, as the asso- ciated Hyolilhcs kiissakcnsis is abundant in the superjacent shales of Division V. As stated by Dr. Redlich, the composition of the fauna is very simple. In Division IV there is an unusually remarkable de- 256 WALCOTT velopment of brachiopods, but only 5 species are present. In Division V the large trilobite, Rcdlichia ncetlingi, may indicate the horizon of the lower beds of the eastern China section or the Middle Cambrian, as the genus ranges up to the summit of the Middle Cambrian. Only 4 other species of fossils occur at this horizon in India. My impression is that systematic search will give a larger fauna from the Salt Range, and that when this is obtained some revision of our present views of the stratigraphic succession and age of the various parts of the known fauna may be necessary. PROCEEDINGS OF THE WASHINGTON ACADEMY OF SCIENCES Vol. VII, pp. 257-366. July 24, 1905. ON BASIC SUBSTITUTIONS IN THE ZEOLITES. By F. W. Clarke. During the past 7 or 8 3'ears a number of researches upon the constitution of the natural silicates have been carried out in the laboratory of the United States Geological Survey. Some remarkable results have been obtained ; and it is now seen that the zeolitic minerals exhibit a high degree of chemical plas- ticity. Sodium and calcium are easily withdrawn from them, and replaced by other metals or basic radicles ; and some of the more striking examples of these reactions are already on rec- ord. In Survey Bulletin 207, for instance, a number of am- monium substitution derivatives are described, such as am- monium analcite, ammonium natrolite, and so on. In Bulle- tin 262, data are given concerning silver and thallium salts of similar character, and the list might be extended almost indefi- nitely. A large and novel field of investigation is now open, which is not likely to be soon exhausted. In addition to the compounds just mentioned, a number of in- teresting sodium, strontium and barium derivatives have been prepared and studied during the past year by Mr. H. C. JNIc- Neil. His work will be published in detail, later; the present communication gives only a summary of his results, together with some theoretical discussion. A few of Mr. Steiger's prep- arations are also cited, for purposes of comparison, and to illus- trate the range of the observations. The mineral analcite has proved to be peculiarly susceptible to transformation, and has yielded derivatives most easily. They may be tabulated as follows : Proc. Wash. Acad. Sci., July, 1905. 258 CLARKE Analcite NaAlSijOfi.HjO. Ammonium analcite NH^AlSioOg. Silver analcite AgAlSisOg.HjO. Thallium analcite TL\lSi206. Strontium analcite SrAl^Si^Ojo. Barium analcite BaAljSi^Oij. The ammonium, silver and thallium compounds, prepared by Mr. Steiger, are all very definite and stable. They were formed by heating analcite with ammonium chloride to 350°, or by fusing analcite with the nitrate of silver or of thallium, and the temperature of the reactions was relatively low. For that reason there was little or no breaking down of the funda- mental molecule. The barium and strontium salts, prepared by Mr. McNeil, were obtained by fusing the mineral with barium or strontium chloride, and afterwards leaching the prod- uct with water, when the new compounds remained undis- solved. The temperature of their formation was unavoidably high, and some decomposition evidently occurred. In fact, in both cases, silica and alumina were found in the leach water in surprising amounts. In the preparation of strontium anal- cite 36.2 per cent, of the original silica, and 23.36 per cent, of the alumina were thus leached out ; and the insoluble residue had the subjoined composition. The composition of the ideal SrAlgSi^Ojo is given in the second column. Found. Calculated. SiOj 50.3S 53.92 AI2O3 26.01 22.88 SrO 23.21 23.20 CI trace 99.60 100.00 The sodium of the original analcite had been completeh' replaced by strontium, but the product obtained was not absolutely pure. With barium analcite the results were better, as may be seen in Mr. McNeil's anal3'ses of three distinct preparations. In the last column I give the theoretical composition of the salt. Found. Found. Found. Calculated. SiOo 43-73 45-6i 45-22 48.54 AljOg 20.75 20.71 21.09 20.57 BaO 32.95 31.36 33.02 30.89 II2O 2.02 1.78 .44 99-45 99-46 99-77 100.00 ON BASIC SUBSTITUTIONS IN THE ZEOLITES •59 Here again a perfect replacement of sodium has been effected, and a close approximation to the true barium analcite is shown in the analyses. Stilbite, which is a calcium alumosilicate, has also been care- fully studied. Mr. Steiger prepared its ammonium and thallium derivatives, and Mr. McNeil obtained a sodium salt by fusing the mineral with sodium chloride. The analvses are as follows : Steiger. steiger. steiger. McNeil. McNeil Stilbite. NH4 Salt. Tl Salt. Na Salt. Na Salt. SiOj . . . • 5.=;-4i 60.73 36-75 6.S.58 64.49 Al^Os . . • 16.85 1S.31 11.74 20.21 19.91 Fe,0;, . . .iS MgO. . . .05 CaO . . . • 7-78 1.66 .68 •79 1.02 Na.,0. . . • 1-23 .12 •15 12.10 13. II (NH,),0 . 7-83 T1,0 . . . 42.94 H^O . . . . 19.01 10.73 7-77 CI ... . i.iS 1-75 100.43 1.68 100.51 100.56 100.03 100.21 Less O. . .26 .40 •38 100.30 100.03 99-83 If we throw out the water of cr3^stallization as extraneous, the molecular ratios give the following empirical formulae for the anhydrous compounds. The tw^o sodium preparations are aver- aged together, and the monoxide bases are united under the general symbol R/O. Stilbite (Ca salt) R..,/Al36„S:ioo(A7:)«- NH, salt R373'Al,5«Si,oooO.,7o5Cl32- Tl salt R:i76 ^'^'376'^'l0O0^2751* Na salt R408'^^l:)67yiioooOmiCl38. The anal3'ses show clearly the e.xtent of the substitutions effected in stilbite, and the formulae indicate the persistency of the original type. Chabazite, like stilbite, is essentially a calcium aluminum trisilicate, and it yields substitution derivatives quite readily. It has, however, a noteworthy tendency to take up extra atoms or groups of atoms, and the analyses consequently show the presence of chlorides or nitrates thus retained. The figures in the following table represent some of these products. 26o CLARKE Steiger, Steiger. Steiger. Steiger. McNeil. Chabazite. NH4 Salt. Ag Salt. Tl Salt. Na Salt. Si02 50. 7S 56.09 34.95 28. 92 54.77 AI2O3 17. iS 19-49 II. 89 10.75 20.36 Fe203 .40 MgO 04 CaO 7.84 2.01 .65 1.52 Na,0 1.28 .24 .40 .28 17-42 K,6 73 (NHJ^O 7-39 AgzO 39.63 TI2O 51. 58 H2O 21. 85 13.45 6.78 4.15 .28 N2O5 6.64 3.54 CI 1.35 6.92 100.10 100.02 100.29 99-87 101.27 Less O .30 1.56 99.72 99.71 From the molecular ratios the following formulae for chaba- zite and its derivatives are deduced. Chabazite (Ca salt) R402^-^l«4Siiooo02807- NH^ salt R.;87 AL(,jiSiio(,o02786Cl3s- Ag salt R608'Alj02SiioooC>280s(^''03)u09- Tlsalt R5-0^-'^U36Sil000O2S7l(>^"O3)l:i7- Na salt R67/-^U:;sSiiooo0289-Cl202- The regularity of these ratios is disturbed by the presence of the CI and NO3 radicles, whose functions will be considered later. The barium chabazite, prepared by Mr. McNeil, shows even greater irregularities, and uniform products were not ob- tained. In one experiment the melt of chabazite and barium chloride, upon leaching, yielded two products, one glassy, the other flocculent, which were partially separable mechanically. A second preparation was entirely glassy. The anal3'ses of these products gave the subjoined results : (A) Glassy, first preparation ; (B) flocculent, first preparation ; (C) second prep- aration. A. B. C. SiOj 43-63 43.17 39-68 AI2O3 17.12 21.24 16.31 BaO 31.58 35.21 40.37 CI 9-53 -55 .S-44 101.86 100.17 101.80 Less 0 2.15 .12 1.23 99.71 100.05 100.57 ON BASIC SUBSTITUTIONS IN THE ZEOLITES 261 The empirical formulx' are as follows : '■' Ba2pf,Al4g.,Sl,ooQ02798Cl37i. ■t> i*'l;',?7-''^.'>-<3'^'lOOo'^31t-l*-''21' ^ l^<*101-^'486'^'lllOo'J3l>H*-'i:l2' Although the replacement of monoxide bases by barium is complete, the products are evidently mixtures, and their ratios are not easy to interpret. The fact that yl, rich in chlorine, and B^ almost chlorine free, both came from the same melt, indicates a breaking down of the molecules. This suspicion is contirmed b}^ a study of the leach waters. In the washings from A and B, Mr. McNeil found 15.85 per cent, of the original silica of the chabazite, with 13.10 per cent, of the alumina. The leachings from C similarly contained 20.3 of the silica and 11.96 of the alumina. The flocculent compound B approxi- mates ver}^ roughly in composition to a salt of the type BagAlg (SiOJ^(Si30g)2, but A is not reducible to any rational formula. It is probable that a series of reactions took place, in which barium chabazite was first formed and afterwards partly broken down or otherwise modified by the continued action of the molten barium chloride. The solvent effect of the latter salt upon silica and alumina is quite marked, and was studied by Mr. jNIcNeil upon the pure oxides or hydroxides. In four ex- periments, one gramme of finely divided silica was acted upon by fused barium chloride for 30 minutes. Upon leaching and filtering, the following quantities of silica were found to have been dissolved : 1. 0.0973 gramme, = 9.73 per cent. 2. .0592 " =5-92 " " 3- -0945 " = 9-45 " " 4. .0771 " — 7.71 " " When aluminum hydroxide equivalent to one gramme of AI2O3 was fused for 30 minutes with 20 grammes of BaCU, 11. 15 per cent, of it went into solution in the washings. Ignited alumina, however, was not attacked. From these experiments it seems probable that when zeolitic derivatives are formed and partly decomposed, the decomposition products pass largely into solu- tion upon leaching. Irregularity in the composition of the residues is therefore to be expected ; and in the order which 262 CLARKE was actually observed in the analyses of barium and strontium analcite. The presence of CI and NO3 in the substituted stilbite and chabazite remains to be interpreted. The simplest explanation of the facts is that adopted by Mr. Steiger in Bulletin 262, where it is assumed that chlorides or nitrates as such are re- tained or occluded by the residues. When' these substances are deducted from the analyses, the remainders agree closely with the theoretical composition of the derived zeolites. But this explanation is not the only one possible. We may imagine that new compounds have been formed, analogous to if not identical wdth such silicates as sodalite or marialite : and it is worth while to examine the data from this point of view. The simplest formula assignable to stilbite, regarding all water as crystalline, represents the species as a mixture of the two isomorphous salts Na,Al,(Si30,),.6H,0, CaAl2(Si303),.6H,0 ; with the calcium compound largely predominating. In chaba- zite we have a similar commingling of (CaNa,)Al2(SiOj2.4H20, (CaNa,)Al2(Si308)2.8H20, the calcium and the trisilicate being most abundant. The true formula} are probably multiples of these, and the anhydrous salts are perhaps best figured by the following expressions, which represent the salts as isomers of nepheline and albite, with their equivalent calcium compounds : Al— SiO,=Al Al— Si30s=Al ^Si04=Al ^SisOg^Al ySiO^^Al ySiaOg^Al Al— SiO,=Al Al— SiPs^Al \si04=Ca ^SL08=Ca Ca Ca I I ySiO^=Ca ySiaOg^Ca Al-SiO,=Al Al— Si30,=Al ^SiO.sAl \si,0«=Al ON BASIC SUBSTITUTIONS IN THE ZEOLITES 263 From formula' of this character, structures of many types are derivable, and some of them may contain chlorine. The sodium stilbite, prepared by Mr. McNeil, may be represented thus : 4AI— SiaOs^Al + A\—Si,0^='Sai + Al— SiO^sNaj \si30s=Al ^SijOg^Al \siOt=Al the last molecule having been formed by loss of silica from the original trisilicate molecule. This set of symbols corresponds to the percentage composition given below, as contrasted with the average of McNeil's two anal3'Ses. Calculated. Found. SiO,, 64.88 65.03 AlO., 20.05 20.06 CaO ) 91 XaaO \ 13-72 12.60 CI 1.74 1-71 100.39 100.31 Less O 39 -S^ 100.00 99-93 The sodium chabazite agrees well with a mi.xture of the sec- ond and third molecules in the expression given above, in the ratio of 5 : 3 ; thus : 5Al,Na3(Si30,).Cl ; 3Ai;Na3(SiO,),Cl ; which compares as follows : Calculated. Found. SiOj 54-90 54-77 AljOs 20.67 20.36 CaO } 1.52 NajO ) 18.S5 17.42 CI 7- 10 6.92 H^O -28 101.52 101.27 Less O 1-52 1-56 100.00 99-71 In silver chabazite, which was prepared by the action of silver nitrate upon the mineral, NO3 appears in place of CI, and we have 3AlAg3(Si303),N03; iAlAg3(SiO,),N03; 264 CLARKE which compares as follows. The 7'cdiiccd analysis was com- puted from Mr. Steiger's analysis by rejecting water, transform- ing Na.,0 into the equivalent amount of Ag.,0, and recalculating to 100 per cent. Calculated. Fouud, reduced. SiO., 37.39 3^-94 AUO3 12.67 12.57 AgjO. . . . : 43.23 43.47 N2O3 6^ 7-02 100.00 100.00 The thallium chabazite is also a nitrate derivative, but the transformation was less complete than in the case of the silver salt. It corresponds to 3Al,Tl3(Si30,),N03; iAl3Tl3(SiO,)3. Reducing the actual analysis by exclusion of water, computing CaO and Na.O into Tl^O and recalculating to 100 per cent., we have Calculated. Found, reduced. SiOj 2S.47 2S.46 AljOj 10.3S 10.5S T1,0 57.49 57-48 N,05 _3^ _34S 100.00 100.00 These agreements are strikingly close, and establish, with a high degree of probability, the existence of the chlorine or nitro- derivatives represented by the formula?. These substances, sometimes mingled with the normal derivatives, seem to exist in the residues obtained in the experiments. Even the barium chabazite " C" agrees roughly with the composition. Al,Ba3(Si30,),Cl + Al,Ba3(SiOJ,Cl ; although much weight cannot be "given to this coincidence. It may be noted, in passing, that Weyberg ' has recently described compounds obtained by fusing kaolin with calcium chloride or bromide, to which he assigns the formulas ' Centralblatt Min. Geol. Pal., 1904, p. 729, and 1905, p. 13S. The calcium chloride derivative had previous! v been noted by Gorsreu, Bull. Soc. Min., 10, 276. ON BASIC SUBSTITUTIONS IN THE ZEOLITES 265 6SiO,.6Al03. 1 2Ca0.4CaCl ; and 5SiO,.8Al03. 1 2Ca0.4CaBr,. These substances, however, have no apparent relation to our zeolitic derivatives, nor can they be simply formulated structur- ally. By fusing kaolin with strontium and barium chlorides he obtained the basic salts 4Sr0.4AU03.7Si02; and 4Ba0.4Al203.7Si02; which, in their physical properties, resemble nepheline. For thomsonite, a silicate of quite different ratios from stilbite and chabazite, three derivatives have been prepared. The anal^'ses are as follows : Steiger. Steiger. Steiger. McNeil. Thomsonite. NH4 salt. Ag salt. Na Salt. SiOj 41.13 42.65 34.99 44.00 AI2O3 29.58 31.34 24.02 32.S5 CaO 11.25 9-23 7-54 2.75 Na,0 5.31 2.48 .74 18.32 (NHJ2O 4.0S Ag,0 24.32 H2O 13.13 10.40 8.39 CI 3-OI 100.40 100. iS 100.00 ic)o.93 Less O .68 100.25 From these the subjoined empirical formulae follow, calculated for the anhydrous compounds. Thomsonite Rsss'Alg^SijoooOneM' NH4 salt R7il6''Al863Sil000O:<693- Ag salt Rse^'AlgogSiioooOagii- Na salt R9i/Aly,,jSiiooo0373oCli,6. The thomsonite itself conforms sharply to the normal ratio of Al3Na3X3, in which X3 represents SiO^ + SiaOg. The propor- tion of Si30g however, is only one eleventh. The sodium deriv- ative, which contains chlorine, appears to resemble the com- pounds derived from stilbite and chabazite, and may be regarded as ver}' near the mixture 266 CLARKE 4A],Na3(Si30,),Cl, ioAl,Na3(SiOJ,Cl, 25Al3Na3(SiO,)3; which may be compared with the reduced analysis as follows : Calculated. Fouud, reduced. SiO, 43.53 43-75 AI2O3 32.02 32.68 NajO 22.11 21.26 CI 3.03 2.99 100.69 100.6S Less O 69 .68 100.00 100.00 The agreement is as close as we could reasonably expect it to be, when we remember that the substance was formed at a temperature above the melting point of sodium chloride. One of the chlorinated molecules, it may be observed, is curiously like kaolin in structure, as a comparison of the probable for- mulas will show. ,0— H yCl Al— SiO,=H3 Al— SiO.^Naj ^SiO^sAl ^SiO^^Al Kaolin. New compound. These expressions have the merit of suggestiveness and may lead to new experiments by and by. The compounds should be derivable the one from the other, if the comparison between them is really sound. In addition to the derivatives mentioned in the foregoing pages, Mr. Steiger has prepared ammonium, silver, and thallium natrolite, thallium mesolite, ammonium and silver scolecite, ammonium leucite, ammonium heulandite, etc. These products are sufficiently described in Survey Bulletins 207 and 262. PROCEEDINGS OF THE WASHINGTON ACADEMY OF SCIENCES Vol. VII, pp. 267-275. Plate XII. July 24, 1905. SIMULTANEOUS JOINTS. By George F. Becker. Joints are almost universally distributed over rock expo- sures, and they are so highly significant that the interest attach- ing to them can never be exhausted. In the present paper I propose to discuss systems of joints of simultaneous or almost simultaneous origin, not with the idea of developing any new principles, but in order to call the attention of geologists and mining men to some details which have been insufficiently con- es ^ sidered although they are of importance in reading the record of mining districts and tectonic belts. Most fine-grained solids which are capable of rupture under given conditions behave similarly. Exceptionally plastic or duc- tile bodies, like aluminium and pure lead, can scarcely be broken by crushing. Some substances again show different resist- ances in different directions ; for example, single crystals, like those of quartz, and masses with a laminar structure, such as slate. But massive rocks in large masses, as well as many limestones and sandstones, cast iron and some forms of steel, are to all intents and purposes isomorphous in that they display practically equal resistances in all directions. Such materials when subjected to forces obey the same laws as softer solids, such as plaster of paris, wax and " ceresin " (the trade name for a mixture of crystalline parafiines derived from ozokerite). It would indeed be perplexing if large blocks of materials com- posed of small crystalline grains irregularly oriented, did not show common properties.' Even clay, so little moistened as to be " stiff " acts as if it were a true solid. 'With glasses, a class of bodies which needs more study than it has received, I shall not deal in this paper. Proc. Wash. Acad. Set., July, 1905. 267 268 BECKER These isomorphous or pseudo-isomorphous substances rup- ture in 2 ways, both of which may often be illustrated in the same experiment. One species of fracture takes place by ten- sion, and is usually characterized by sharp curvatures and un- ■even surfaces ; the mass is torn asunder. The other method of fracture is by "shearing motions," due to pressure; the mass is ctit to pieces by surfaces which are often, and in fact char- .acteristically, flat and smooth. Persistent joints and systems of joints are due to pressures ■while the partings between columnar basalts and the very sim- ilar cracks in drying mud arise from tension. In mining dis- tricts tension cracks often appear as a subordinate phenomenon where faulting has forced apart slaty walls, leaving splinters attached to both sides of a fissure which itself arose from pres- sure, and I have even seen similar occurrences along the crev- asses of a glacier. So, too, when a cylinder of relatively mild steel is crushed, the bulging edge of the mass may show merid- ional tension cracks due to the increase of the equatorial periph- •er}', even when the interior displays diagonal fracture. The behavior of cylinders, however, has some peculiarities which will be mentioned presently. Rocks are often ruptured without much preliminary^ deforma- tion, and it is easiest to begin with the hypothesis that the de- formation is negligibly small. The effect of larger deforma- tion can be traced after the principal characteristics of rupture ihave been examined. It is also convenient to consider first of :all a cubical or at least a rectangular mass. Suppose then that a cube of rock (shown in Fig. i, PI. XII) is subjected to a perpendicular and evenl}^ distributed force acting on its upper and under surfaces while the face A and that opposite to it are supported in such a way as to obviate rupture. Then the effect of force will be to produce ruptures along planes perpendicular to A and inclined in opposite directions at an angle of 45° to the line of force. Two systems of joints will result forming angles of 90° to one another on A or on sections parallel to this face. On the face of the cube marked B and that opposite to />', the traces of these joint planes will be hori- zontal straij^ht lines, while on the surfaces on which the forces Proc. Wash. Acad. Sci., Vol. VII. Plate Xil. SIMULTANEOUS JOINTS 269 act, that is to say, on the top and the bottom of the cube, the traces of the joints will be parallel straight lines perpendicular to A. By these means the cube will be divided into a number of square prisms so placed that the diagonals of the squares are either horizontal or vertical. It has come to be pretty generally recognized that two sys- tems of joints such as those described may be produced by a single force acting at an angle of about 45° to each system. If the deformation antecedent to rupture were of sensible amount, the joints would make angles of somewhat more than 45° with the line of force. It is not so generally understood that 4 or even more than 4 systems of joints may be due to a single force. This case is less common than that of a smaller number of partings, and is usually confined to limited areas, but it is not infrequent, particularly in the disturbed regions which ores so much affect. Imagine a second cube, shown in Fig. 2, similar in all re- spects to the first excepting that the faces J5 and its opposite are supported instead of faces A and that opposite to it ; then of course the result will be the formation of prisms whose square cross sections will be visible on B instead of on A. If on the other hand the cube is not supported on any side, or if the resist- ance perpendicularly to the line of force is uniform, then these 2 systems of rupture will take place simultaneously, so that on both A and B there will be systems of cracks at 45° to the line of force intersecting one another at 90°, while each of these faces will also show horizontal cracks. By these means, the cube will be divided into octahedral and tetrahedral blocks as indicated in Figs. 3 and 3«. Such rupturing can be and has been experimentally verified, for instance by Daubree ; but I know of no experiments so perfect as instances which may be observed occasionally in rock exposures. In experiments on cylinders, the lines of rupture are often found to be conically disposed, and this mode of rupture requires explanation, especially as corresponding phenomena are so rare in nature that I have never met with them. When a cylinder is linearly compressed (say vertically) between masses of much more rigid material, the cylindrical form is not preserved, the 270 BECKER mantle of the cylinder expanding to the shape of a barrel. The reason for this is that intense friction is produced by the effort of the end surfaces to expand in contact with the rigid planes exerting the vertical pressure. I have experimented somewhat elaborately on the character of this strain and have determined the position of the strain ellipsoid at 64 points on a vertical cross- section. The greatest axis of the ellipsoid lies in the plane passing vertically through the center of the cylinder, but it is not horizontal ; it is inclined to the horizontal at an angle which varies with the distance from the central vertical axis of the barrel-shaped mass. The least axes of the ellipsoid also lie in the vertical central cross-section of the mass and the surfaces ^ of " maximum tangential strain " are conoidal with their apices in the axis of figure. It is along these latter surfaces that rup- ture due to pressure must occur if at all, as I showed long ago. At any one point of such a cylinder the strain is homogeneous and exactly comparable to that in a uniformly strained cube. The peculiarity of experimental results on cylinders lies in the radial symmetry of the stress system. If it were possible to crush cylinders between frictionless sur- faces, so that the deformed blocks would retain a uniform diam- eter, the strain ellipsoids would have 2 equal horizontal axes, and, if the mass were ideally homogeneous, it is difficult to see what would determine the position of the ruptures. But this is not an important question. In real matter the resistance could not be exactly the same in all directions and 2 S3"stems of joints would form as in the cube. In a cubical mass, or in one of square cross-section, the cracks will be perpendicular to the sides of the cube as explained above, because this is the posi- tion of least resistance, or because a unit area of rupture in this orientation goes farthest towards relieving the strain in the yielding mass. In the lithosphere, when crushing or jointing takes place, the masses exerting the pressure are almost invariably little more resistant than the rock which is ruptured. It is very seldom, ' U. S. Geol.[Suiv. Bull., 241, 1904. The surfaces of rupture are such as would be obtained by rotating Fig. 14 of that bulletin about its smallest diameter, but if the deformation were small these surfaces would be indistinguishable from right cones. SIMULTANEOUS JOINTS 27 1 therefore, that those features of experiments are observable in nature which depend on great differences in strength between the material tested and the apparatus used in testing. In cases of uniform lateral resistance then, at least 4 systems of joints may form simultaneously as the result of the action of a single force, separating the rock into octahedrons and tetra- hedrons. Very minute differences in resistance would of course modif}^ the development of the octahedral faces, but the 4 sets of planes at least would be, and often are, perfectly distinct. In experiments the 4 surfaces are so oriented as to be readily distinguished, but in nature such orientation is relatively rare. Tectonic forces are not usually exactly horizontal or exactly vertical, and the exposures due to erosion or other causes are generally inclined surfaces. Now, granting the simplicity and symmetry of the fissuring, it is not at once evident how the joints would be distributed on a plane taken at random through the jointed mass. It is really an easy matter to project the fis- sure systems onto a random plane, and requires only the appli- cation of rudimentary descriptive geometry ; but the step has not heretofore been taken, while it is interesting to compare the results of the process with natural examples. The plots also indicate how observations on a random plane may most simply be dealt with when it is desirable to reduce field data to a sym- metrical orientation and to find the line of force. On account of its bilateral symmetry the octahedron gives a convenient starting point for constructing a random section. This octahedron will not be a regular one, inasmuch as the angle between 2 planes taken over the coign will be a right angle, and the 8 triangles of the octahedron will therefore not be equilateral. Fig. 4 shows such an octahedron so drawn as to expose to view only 2 of the triangular faces. Fig. 5 shows the same octahedron in plan and Fig. 6 in elevation, 4 faces being visible. In order to display the fissure systems of the jointed mass taken on a random plane, any 3 points on the edges of the octahedron may be selected in Fig. 6, such as /, in, n. These points of course fix the plane. By evident and familiar methods 272 BECKER the random plane can now be brought into the plane of the paper as shown in Fig. 7/ where also the direction and amount of dip of the 4 surfaces is shown as determined by an easy con- struction. Finally from the data of Fig. 7 and the hypothesis that the fissures are evenly distributed in space, it is possible to display the traces of the joints on the random plane as shown in Fig. 8. Every observer who has paid attention to systematic joint- ing, will recognize the similarity between Fig. 8 and certain field occurrences ; it is noticeable, too, that the effect produced by Fig. 8 is much more complex than the indications of Figs. 1 and 2 might lead one to expect. Such a joint system as is displayed in Fig. 8 does not ordinarily extend over any large region of country and the reason is that in nature, as a rule, the unequal support afforded by surrounding rock masses is sufficient to suppress one or more of the joint systems. As pointed out above, it is only when the resistance perpendicular to the line of force is the same in every direction that all 4 systems of joints will appear. On the other hand, even more complex systems are sometimes found locally developed for reasons which will be set forth a little later. The process of construction outlined can be reversed, so that if the spacing and dip of the fissures on the random plane were given, the quadrangle of Fig. 7 could be drawn and the posi- tion of the octahedron, or the line of force, determined. There are natural cases in which this reduction would be instructive. In the construction of Fig. 8, it has been assumed that the permanent strain at rupture was insignificant and, on this hypothesis, the faces of the octahedron are isosceles triangles with one angle of 70° 32' (cos"' 1/3) and 2 equal smaller angles. 'Transfer the intersections of the random plane from Fig. 6, PI. XII, to Fig. 5, PI. XII; draw also in 5 a square (parallel to the plane of 5) which will contain the point at which the random plane intersects the axi& of the octa- hedron. Then the line rs is common to 5 and 7 and rotation of 5 about the line rs yields 7. In constructing Fig. 7 it is necessary to have a vertical section through Fig. 5 perpendicular to rs. In finding the spacing for Fig. 8 it is convenient to have 2 other vertical sections of 5, one along the line /;« and the other along /«. It is unnecessary to state that computation might be substituted for construction if a high degree of accuracy were called for. SIMULTANEOUS JOINTS 273 If permanent deformation of notable amount preceded rupture, the single angle would be greater than 70° 32'. In the foregoing, it has been supposed that the joints are mere cracks and that no measurable amount of motion occurs on any of them. This is often approximately true in nature. The throw of the faults produced on the joints is sometimes so small as to be microscopic, and I have measured great numbers of such dislocations which were expressible only in hundredths of an inch. Nevertheless, it remains true that a joint does not form except in obedience to a tendency to faulting. When a block of any material is squeezed between a plunger and an anvil, it does not crack until it can yield no further without cracking. In other words, rupture takes place in order to permit of a closer approach between plunger and anvil than is consistent with the continuity of the block subjected to experi- ment. These cracks undergo a certain throw in the very act of forming. In order to perceive the nature of the dislocation it is best to assume that it reaches a considerable amount. I will suppose for example that the shortening of a ruptured block is 10 per cent. Then the dislocation must be of the t3'pe represented in Fig. 9, though a certain variety in the disposi- tion of the residual fragments is evidently possible. Now, Fig. 9 shows several large faults, and the shortening evidently could not have been achieved without these or equivalent dislocations. It is often assumed that when one fissure faults another the latter is the older, but this inference is not justifiable and they must often be of exactly the same age. Very frequently inter- lacing quartz veins may be studied in which the quartz is con- tinuous from one system of ruptures to the other, and in which there is every indication that the ore was deposited at a single epoch. Such instances show no slickensides within the veins, but even when there are slickensides these may possibly be due to fresh movements on the old surfaces after ore deposition is finished. Of course I do not mean to deny that cases occur in which some veins are younger than others with which they are associated. I merely mean to w^arn colleagues against hasty inferences in regard to the relative age of veins. If such a system of dislocations as is shown in Fig. 9 were to 274 BECKER be produced under any considerable external pressure, it is manifest that the several residual fragments might be pressed against one another with ver}- great force. In such a case the mere grinding action accompanying the dislocation would tend to produce further ruptures in the residual fragments. It is not easy to work out a satisfactor}* theory of the distribution of such secondary fractures. It is fairly evident, however, that in an extensive complex, of which Fig. 9, PI. XII, may represent a small portion, there is likely to be a repetition of identical con- ditions, so that many separate blocks will be similarly situated with reference to their neighbors. If secondary rupture takes place, such blocks will be similarly affected and their fissures will be parallel, but probably not continuous throughout the mass. The more numerous the groups of similarly oriented blocks after the original jointing, the more numerous will be the systems of blind secondary joints. These latter may in- deed be regarded as subsequent to the original joints, yet the difference in age may be only a second or two and the brevity of the interval should be taken into account in reading the his- tory of the district. To me it appears questionable whether in a region once jointed by a system of forces, the application of a new system of forces could produce a fresh set of joints systematically ar- ranged. The resistance of a jointed rock mass is so extremely unequal in different directions, and so small in manv of them, that fresh movements on the old joints or the reduction of the formation to a chaotic rubble seems more probable than any- thing comparable with renewed systematic jointing. Thus forces acting on a brick wall usually produce cracks which fol- low the joints between bricks, and if bricks were not designedly laid so as to "break joints," and carefully cemented besides, cracked bricks in dama r ^ - ■■- Y//My//'m///M-- ' - . — - — -Y/Z/J^^^-^^r^=^-:^^^^^/A— .— - — — / wm GLASS ^^y ^ ^ Fig. I. in a saturated solution of constant temperature to grow clear crystals a centimeter in diameter which would raise a weight of a kilogram through a distance of several tenths of a millimeter. The crystal was placed upon a piece of plate glass in a beaker containing saturated solution of the same material, and loaded as desired. Knowing the weight raised, it appeared an ex- ceedingly simple matter to determine the force required, since it was only necessary to ascertain the actual area of contact be- 286 BECKER AND DAY tween the weight and the crystal. Here, however, an unex- pected difficulty was encountered. The face of the crystal in contact with the lower surface of the vessel is not plane and does not even distantly approach this configuration. On the con- trary, a terraced cup forms below the crystal so that the bearing surface remains a mere edge throughout its growth. The ac- companying figure may serve to give a fair idea of a section through the crystal at any time during its growth. The closer the examination made of these cupped faces the smaller the actual bearing surface was found to be. One method of determining this area is obviouslv to print it off on a piece of paper, but it was found that the edges were often so fine that the printed lines appeared several times broader than the true edge. The process finally adopted was this : A fine micrometer screw was mounted vertically so as to carry the crystal downward in a motion accurately parallel to itself. Chlorophyll made up with fat was selected as printing ink. It gave a good color in extremely thin la3'ers, showed no disturb- ing capillary action while the imprint was being made, and ex- erted no solvent effect upon the crystals. A very thin coating of this mixture upon bristolboard made a good inking pad. No paper was found sufficiently hard and flat to take the impression accurately, and our ingenuity was considerably taxed to find something which would do so ; finally we hit upon the following device : White celluloid was dissolved in ether and alcohol and flowed upon a glass plate somewhat as a photographic plate is coated. When the volatile solvent had evaporated a level surface of opaque celluloid remained behind which was ex- tremely smooth and flat. On this surface prints of the crystals could be taken, portions of the impressions often being so fine that they quite escaped notice unless seen through a reading glass. They would defy reproduction in illustrations. The measurement of the minute areas thus recorded is a mat- ter of great difficulty and uncertainty, and the force per unit area which the crystals exert is, therefore, hard to estimate. It was at once evident that it amounted to man}' pounds per square inch, and as observations multiplied, it became reasonably cer- tain that it is actuallv of the same order of maiinitude as the THE LINEAR FORCE OF GROWING CRYSTALS 287 ascertained resistance which the crystals offered to crushing stresses. Moreover, there is reason to believe that this area changes constantly as the crystals grow, and is less for a smaller load than for a larger one. The upper contact surface of the crystal is also variable, but always much more perfect than the lower. Relatively large areas in perfect contact with the glass plate which supports the weight were frequently found by careful printing. Following these determinations, confirmatory experiments were made upon other salts (copper sulphate, ferrocyanide of potassium, lead nitrate), the results being practically the same as those found for alum. It is manifest that we here have to do with a force of great geological importance. If quartz, during crystallization, exerts a pressure on the sides of a vein which is of the same order of magnitude as the resistance which it offers to crushing, then this force is also of the same order of magnitude as the resistance of wall-rocks, and it thus becomes possible that, as indicated by observation, the Mother Lode and other great veins have actually been widened to an important extent, perhaps as much as lOO per cent., or even more, by pressure due to this cause. In mining regions the whole country is frequently intersected with systems of quartz veins. Some of these, of course, are of notable size and capable of being worked, provided the quartz is sufficiently rich ; but many more, a number vastly in excess of the large veins, are thin sheets no thicker than a card, in- capable of profitable exploitation by man, though there is little question that these tiny veins have often contributed the bulk of the gold to placer deposits. In such a country there is almost no limit to the effect which might be produced by the force of the growing crystals, and the displacement might readily be so great as to induce important new fissures or important renewed movements on old fissures. Again, in a vein where auriferous quartz is being deposited, the growth of crystals may readily extend the space in which successive crops of crystals might grow, so that in certain cases (for instance on an inclined vein, like the Comstock Lode, near the cropping) the deposition of ore might continue almost indefi- nitely and the total deposit thus increase with time. 288 BECKER AND DAY To what extent detailed observations will show a history of this kind for ore deposits, it is too early to say, but it is cer- tainly worth while to draw the attention of geologists and min- ing engineers to the possibilities thus presented, and to dynamic conditions which may prove important as well as interesting. To the physicist also the phenomena cannot be uninteresting. The power which roots exhibit to prize apart large building stones we are content to classify as "vital" and mysterious. We cannot so easily dispose of the similarly intense force with which, as it appears, inorganic molecules drive themselves into place, much as oakum is driven into the seams of a ship by a caulking iron. We hope to be able to continue this study at some future time. PROCEEDINGS OF THE WASHINGTON ACADEMY OF SCIENCES Vol. VII, pp. 2S9-299. Plate XIV. July 24, 1905. AN INTERESTING PSEUDOSOLID. By George F. Becker and Arthur L. Day. As is well known, Professor J.J. Thomson's investigations lead to the hypothesis that a molecule is a highly complex body consisting of great numbers of minuter particles called cor- puscles, so that a molecule would be more nearly comparable to a swarm of meteorites than to, let us say, a planet. In considering this theory, it occurred to us that a model might be made from a mixture of liquid and gaseous ingredients, the physical properties of which would very closely resemble a homogeneous solid made up of such complex molecules. A bubble of soap solution, or any other viscid liquid would enclose great numbers of molecules of oxygen and nitrogen, all of them in rapid motion, and representing the corpuscles of Thomson's molecule, while the surface tension of the bubble itself would replace the attraction of the systems of corpuscles towards some interior point or points. The foam which ac- cumulates in sheltered places on a rock-bound sea-coast, the beaten white of an egg or the whipped cream products of the pastry cook's art, represent very stable aggregates of such imitation molecules while they are of a size and character to admit of manipulation and study. In order to obtain experimental evidence as to the properties of such foam, we prepared a prismatic mass of fine soapsuds and attempted by torsion to ascertain whether its behavior re- sembled that of a viscous liquid or a true solid. It is well known that the behavior of a twisted prism is very characteristic of the state of the matter composing it. A viscous liquid, such Proc. Wash. Acad. Sci., July, 1905. 289 290 BECKER AND DAY as sealing wax, under torsion moves in planes at right angles to the axis of torsion in such a way that each plane after torsion remains a plane. On the other hand, in a solid mass even of very feeble rigidity, surfaces originall}- plane and at right angles to the axis of torsion become warped or otherwise dis- torted surfaces after torsion. A prism of fine soapsuds was -experimented upon by laying a fiber of silk around the per- iphery at right angles to the axis and then twisting the mass. The silk fiber immediately assumed the warped outline charac- teristic of solids and showed that, in this respect at least, the foam had the properties of a solid body. After some qualitative trials, it seemed worth while to make at least an effort at measurement upon a solid of this character, one principal reason being that distinctl}" finite displacements (amounting to 30 or 40 per cent.) could very readily be obtained with it. Plateau's solution was at first thought to offer the most promis- ing material with which to prepare the pseudosolid, but we did not find it as serviceable for this purpose as it has proved to be for some others. We made up the solution from various olive oil soaps, then from " C. P." sodium oleates furnished by dealers, and finally with 2 preparations of very pure oleate made in the chemical laboratory of the Geological Survey. We were unable to verify Plateau's conclusion that increased purity produced increased tenacit}- of film ; on the contrary, a plain solution of yellow soap mixed with glycerine in random proportions produced quite as rugged films. It was our experi- ence, however, that all these films lost their toughness upon being beaten into foam, and that the prisms of such foam de- teriorated so rapidly that no measurements could be made upon them. We next turned to the white of egg, with which we attained a considerable measure of success. The white of a fresh egg (it is imperative that it be very fresh), in which about an equal volume of powdered sugar has been completely dissolved, can be beaten to an extraordinarily fine homogeneous foam from which prisms can be cut, mounted, and measurements covering several minutes made upon them without any considerable AN INTERESTING PSEUDOSOLID 291 deterioration taking place. It also proved possible to strain these prisms to fracture and to lay them aside to dry, which they do with but little change of form, and to study or photo- graph these fractures at leisure. Many of these specimens resembled fractured close-grained rock so closely in the photo- graph as to be practically indistinguishable from it. The apparatus with which the measurements upon these prisms were made was of extraordinary sensitiveness and admitted of very rapid manipulation. A fine analytical balance was mounted with a mirror at the top of, and at right angles to, the beam, which could be observed with a telescope and vertical scale at a considerable distance, thereby furnishing a very sensitive measure of the Fig. I. motion of the beam. A die was then prepared with which cylinders of uniform size could be cut out of a mass of foam and deposited quickly upon one of the pans of the balance. The w^eight of the cylinder was compensated by an equal weight in the other pan. A glass bridge was then fixed in posi- tion over the foam cylinder and the pan raised until the upper surface of foam was in perfect contact with the glass bridge. The illustration (Text-fig. i) will serve to show the distribufion of the essential parts of the apparatus. Having placed our cylinder in position between 2 clean glass 2Q2 BECKER AND DAY plates, the movable scale pan and the fixed bridge, weights could be added in the other pan of the balance which would serve to compress the cylinder, or in the same pan to exert a tensile stress upon it and the change in length be recorded very accurately by the observer at the telescope. A simultaneous measurement of the diameter was obtained b}- mounting 2 cameras at right angles to each other and focusing them sharply upon the periphery of the cylinder so as to record 2 perpendicu- lar diameters (Fig. 2). The back of each of these cameras Fig. 2. was provided with a permanent slit in front of the plate in such a way that the rotation of the plate behind the slit gave succes- sive images of the same portion of the cylinder to the same scale (magnified about 4 times) upon the same negative. The operation was then a simple one, requiring 2 observers : As soon as the foam cylinder had been deposited upon the pan, the bridge placed over it and the balance had reached its posi- tion of rest, simultaneous photographs were made with the 2 cameras, and at the same moment a reading of the length with the telescope and scale. A small weight was then quickly added in the other pan. This produced a slight compression, the pan came to rest almost immediatel}', whereupon a second reading of the telescope and scale was made and a second pair of photo- Proc. Wash. Acad Sci., Vol. VI Plate XIV. Composite photo,<;riiph showing path of cafh component particle of a foam cylinder. AN INTERESTING PSEUDOSOLID 293 graphs taken with the cameras. This operation occupied per- haps 20 seconds, after which a second increment of weight could be added and the proceeding repeated. It was thus pos- sible to make perhaps 6 measurements upon each solid within a period of 2 minutes, during which the foam showed no deterio- ration whatever.^ Experiments on Poisson's ratio were also made by compressing cylinders of foam between a fixed plate and a movable plate attached to a micrometer scale, the results being recorded photographically. The photographs were made with the help of 2 powerful arc lights equipped with reflectors and the most rapidly moving shutters we could obtain ready made. The photographic expo- sure therefore occupied perhaps a i/ioo of a second. The remainder of the process was mechanical. The plates were developed and measured with great accuracy upon a com- parator, the mean of 5 measured diameters constituting the diameter which was used in each calculation. It will be seen by a glance at the accompanying table that the results of these measurements afforded a greater accuracy than is usually obtained upon the common solids of laboratory practice, with which no more than i per cent, of displacement can be attained. It was also possible to make a series of photographs of the entire foam cylinder after successive increments of compression and then by superposing the plates to obtain accurate traces of the path of each component particle (bubble). A " composite " photograph of this character is reproduced in PI. XIV. It was found that the lines of flow were parabolic {xy" = const.), as they should be in a solid, according to theory, which is not well illustrated by most experiments. It was also found that such masses of foam could be ruptured, and that in this respect they behave sensibly like very rigid solids, such as steel, cast-iron, or rock, in spite of the fact that 1 The apparatus here described was obviously intended to furnish data for a complete discussion of the elastic constants of the pseudosolid, including the relation between force and displacement, but the lack of a stable pier in our labor- atory made it impossible to carry out the latter measurements and was the imme- diate cause of the suspension of the work until more favorable conditions should be available. J94 BECKER AND DAY TABLE. Photograph No. Length, j Width, y. X. Poisson's Ratio. o- = . soon- er' = a" + Compression, 24-1 18.952 16.210 — — — — -2 18.827 16.268 0.542 0.542 0.502 4-0.042 +0.040 -3 10.702 16.316 .490 .496 •505 — .010 — .009 .-4 18.577 16.369 .489 .496 •507 — .011 — .011 25-2 18.452 16.429 .502 .512 .510 + .002 + .002 -3 18.327 16.482 •497 .509 •512 — .003 — .003 -4 18.202 16.529 .482 .497 .515 — .018 — .018 Compression. 22-1 20.577 16.328 — ■ — — — -2 20.327 16.420 0.459 0.464 0.504 — 0.041 — 0.040 -3 20.077 16.523 .483 .491 .509 — .017 — .018 -4 19.827 16.614 .468 .481 .514 — ^032 — .033 23-2 19-577 16.717 •473 .490 •519 — .027 — .029 -3 19.327 16.821 •474 •497 .524 — .026 — .027 -4 19.077 16.936 •483 .511 •529 — .017 — .018 Compression. 30-1 20.577 16.016 — — — — -2 20.077 16.217 0.507 0.516 0.509 +0.007 +0.007 -3 19^577 16,418 •498 .516 •519 — .002 — .003 -4 19.077 16.630 • 497 .52b .529 — .003 — .003 31-2 18.577 16.847 • 495 •534 •539 — .005 — .005 -3 18.077 17^065 •490 •539 •550 — .010 — .011 -4 17^577 17.311 •493 •555 .561 — ,007 — .006 Tension. 28-1 18.077 15^760 — — — — — -2 18.577 15-553 0.484 0.475 0,490 —0.016 —0.015 -3 19.077 15-363 •474 .455 ,481 — .026 — .026 -4 19-577 15-143 •501 .472 .471 + .001 + .001 29-2 20.077 14.962 •495 •458 .462 — .005 — .004 -3 20.577 14-756 •509 ,461 •454 + .009 + -007 -4 21.077 14.598 •499 ,444 •446 — .001 — .002 The values of Poisson's ratio are computed from the 3 equations, logy-logy^ a = * oc^ ^Ay .'- = 2^ f, _ J ^ \. The equation for ct results from the assumption that the loadstrain relation is an exponential.' a' is the ratio of the observed lateral contraction to the linear elongation expressed in terms of the initial dimensions ; and c^' is the same ratio, the lateral contraction being computed on the assumption that the volume remains constant.^ ' Amer. Journ. Sci,,Nov., 1S93, p. 34S. ^ Stewart iS: Gee, General Physics, p. 194. AN INTERESTING TSEUDOSOLID 295 the absolute value of the modulus of rigidity of the foam is ex- tremely small. The ruptures took place at rather more than 45° to the direction of the compressive force, and in symmetri- cal cases 4 systems of fissures were developed in 2 planes at right angles to each other, as has been found by Mr. Adams in his experiments on marble, as well as by man}- earlier observers.. According to a theory of elasticity published by one of us in 1S93, the continuity of a solid under linear compression should be represented by the simple formula xy°' = constant, and the attempt was made to determine the value of