SBHHBBw&ln E& mHin 't^l£&Mmf£i PS -A ''■"' a : vmmUfi :/*v£A^_'V, elf Ro. k J2c/,/JfJfe. J / r^M * Boston Public Library- Do not write in this book or mark it with, pen or pencil. Penalties for so doing are imposed by the Revised Laws of the Commonwealth of Massachusetts. This book was issued to the borrower on the date last stamped below. \ \ ! "1 J J J 1 FORM NO. 609; 6,12.33: 575M. Digitized by the Internet Archive in 2010 with funding from Boston Public Library http://www.archive.org/details/paperschieflyanaOOwild PAP E RS, CHIEFLY ANATOMICAL PRESENTED AT THE PORTLAND MEETING OP THE AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE, AIJG-TJST, 187 3 By BURT G. WILDER, M.D., PROFESSOR OF COMP. ANATOMY AND ZOOLOGY, CORNELL UNIVERSITY, ITHACA, N. Y. SALEM, MASS. SAI.EW PRESS, CORXER OF LIBERTY ABD DERBY STREETS. 1874. PAPE RS, CHIEFLY ANATOMICAL PRESENTED AT THE PORTLAND MEETING OF THE AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE, JLTTO-TTST', 1873 By BURT G. WILDER, M.D., PROFESSOR OF COMP. ANATOMY AND ZOOLOGY, CORNELL UNIVERSITY, ITHACA, N. Y. SALEM, MASS. SALEM PRESS, CORNER OF LIBERTY AND DERBY STREETS. 1874. • 384 1(1 *}' CONTENTS The Outer Cerebral fissures of Mammalia, especially the Carnivora, and the limits op their homologies ...... 214 Cerebral variation in domestic dogs and its bearing upon scientific phrenology .......... 234 Lateral asymmetry in the brains of a double human monster . . 250 The papillary representation of two arms in a double human monster 251 The habits and parasites of epeira riparia . . . . .257 The nets of epeira, nephila and hyptiotes (mithras) . ... 264 The need of a uniform position for anatomical figures ; with a recom- mendation that the head be always turned toward the left . 274 Lateral position of the vent in amphioxus, and in certain batrachian LARV.E . . . . . . . . . . .275 Composition of the carpus in dogs ....... 301 Present aspect of the question of intermembral homologies . . 303 Variation in the condition of the sense organs in fcetal pigs of the same litter .......... 303 The pectoral muscles of mammalia 305 Variation in the pectoral muscles of domestic dogs . . . ,308 (213) The outer Cerebral Fissures op Mammalia (especially the Carnivora) and the Limits of their Homology. By Burt G. Wilder, of Ithaca, N. Y. Naturally, human brains have been most extensively studied, and chiefly those of adults ; some have compared fcetal brains with those of Quadrumana but the existing doubt and disagreement,* with the lack of any generally recognized basis for the determina- tion of fissural homologies, suggest the need of a different method of study ; and as the main object of this and the next paper is to throw doubts upon the value of current opinions respecting brains, it is proper to state the materials upon which my opinions are based. It will be understood therefore that, unless otherwise stated, my present generalizations are based upon these materials only, and are subject to revision when a larger number of speci- mens is at my disposal. Where but a single drawing or diagram was made, it generally represents the outer surface of the left side ; the second usually the right side, or the upper (dorsal) surface ; and the mesial and ventral surfaces were added if their peculiarities required and time permitted. All of these drawings and diagrams were made by myself, and most of them were exhibited at the meeting. The varieties of dogs' brains will be given in the next paper. On the following page I give a list of original preparations and drawings of mammalian brains made since July, 1871, and forming the basis of this and the following paper. * A good example of this is stated by Ecker who includes the anterior central lobe With the frontal, while Gratiolet and Bischoff include it with the parietal. This note, with some other matter which delay in publication has permitted me to in- sert, should bear date of December, 1873. (214) B. NATURAL HISTORY. 215 SCIENTIFIC NAME. Homo sapiens. Macacus Cynocephalus., ^Canis familiaris Canis occidentalis Vulpes fulvus Felis catus, var. domesticus.. Felis leo, var. Africanus Felis leo, var. Asiaticus Hyrena vulgaris Ursus Americanus Procyon lotor Putorius Noveboracensis Sus scrofa Eqmis caballus Equus Bos taurus Ovis aries Capra asgagrus Capra segagrus, var Cariacus Virginianus. Cam-el us Bactrianus , Mus decmnanus Mus musculus Arctomys monax Fiber zibetliicus Sciurus Hudsonius Cynomys Ludovicianus Hesperomys leucopus Scotophilus fuscus Didelphys Virginiana Genera, 28; Sp.,32; Var., 40-45. POPULAR NAME. Man White-faced India Monkey. Baboon Monkey Domestic Dog Gray Wolf Red Fox Domestic Cat African Lion Asiatic Lion. Striped Hyama Black Bear Raccoon Weasel Swine Horse Mule Cattle Sheep Goat; Cashmere Goat Red Deer , Two-humped Camel Brown Rat Mouse Woodchuck Muskrat Red Squirrel Prairie Dog Deer Mouse Brown Bat Opossum Total .1 53 6 1 1 5 29 3 2 42 1 1 1 I 3 1 24 7 1 20 IS 1 2 4 1 2 2 45 216 B. NATURAL HISTORY. These specimens form part of a collection to illustrate the neu- rology and embryology of domesticated animals, which Professor Agassiz* authorized me to make for, and at the expense of, the Museum of Comparative Zoology in Cambridge.! It will be seen that the above list of one hundred and eighty- nine individuals includes about twenty-eight genera, represented by about thirty-two species, and about forty-five varieties, the numbers varying according to differing estimate of the taxonomic relations of the individuals. The size of human brains, the expense of their preservation in numbers, the rarity of apes' brains, and especially of foetal speci- mens, together with the complexity of the fissural pattern which man and Quaclrumana have in common with herbivorous mammals, are additional reasons for selecting other subjects. A simpler fis- sural pattern exists with the Carnivora. Among these the wild Canidce (fox, wolf and fennec) occupy a position midway between the Viverridce and Mustelidoz on the one hand, and the domestic dogs, the Felidce, Ursidce and Hycenidce, on the other. That is, all the main fissures found in Carnivora are present in the fox, but uncomplicated by contortions and by secondary fissures. Method of Preparation. :[ — The present paper treats only of those cerebral fissures which are visible from the outer side of a brain properly prepared. Heretofore all brains have been har- * Since this paper was written, he who inspired it hasjfinished his work in this world. As his student, his assistant and fellow-teacher, I cannot refrain from expressing my sense of bereavement. To me he was not only a great naturalist; he. was the wisest of teachers and the kindest of friends; whose criticism was a healthy stimulus and his praise a sweet reward. f Those who bear in mind that not a single brain was preserved from an entire menagerie which was suffocated in Boston about thirteen years ago, and that no simi- lar collection exists in this country on account of its great cost in time, alcohol and means of displaying, will appreciate the extent of interest which Prof. Agassiz felt in this special undertaking; and while, as Professor in one institution, I must regret that the result of any of my work should leave it for another, yet as it must be years before my own or any other museum can command the means required for such a special col- lection, I am really grateful for the opportunity of using this material as it came for the instruction of my students, and by this kind of work, avoiding for a season, the outside drudgery in the way of popular writing and lecturing, to which the existing financial condition and policy of the average American University compel its Profes- sors continually to resort, whether ready or not, to the impairment of their powers, and the detriment of the interests of the institution to which they would rather devote all their time, their energies and their enthusiasm. X It may seem that these remarks might be omitted or placed at the end of the paper ; but I have become so impressed with the often repeated dictum of Prof. Agassiz that " the method affects the result," that I wish to submit mine at the outset. B. NATURAL HISTORY. 217 denecl while resting upon their base. They become unnaturally flattened, and are then generally figured from above only. Like so many other methods borrowed from anthropotomy, the common manner of extracting the human brain is seldom applicable to those of animals ; the skull, as well as the brain, is more useful if ver- tically bisected, and this seems to be the only way of insuring the safety of the olfactory lobes and the appendicular lobule of the cerebellum ; the former are rarely figured of their full size (as, for example, in the cat and cheetah. Trans. Zool. Soc, vol. i, pi. xx), while the very existence of the latter seems often unsuspected even in those animals where, by extracting the brain after bisecting the skull, I have found it of great size. In a future communica- tion, I intend to illustrate this peculiar organ and make some remarks upon its connections, mode of formation, function and zoological significance. It is particularly large in the bear but small or wanting in the lion and in cats ; being often bulbous at its extremity, the utmost care must be exercised to avoid breaking the pedicel, and I have found it easier to effect the dislodgment by throwing air behind it with a small blow-pipe. Figure 1 rep- resents from below the left appendicular lobule (A L) of a Chinese clog ;* it seems to be a protrusion of a portion of one of the horizontal series of convolutions. I am inclined to think that in most cases, the way to preserve the entire brain in its natural form is to bisect it either before or after extraction, and to place each half upon its mesial surface in a flat-bottomed vessel of alcohol. As it rapidly loses weight in alcohol f and gains in water, and as handling out of these fluids is apt to distort it, I would recommend weighing each half of the head before and after extraction ; the difference gives the exact weight of the brain ; but as the apparatus which I employ (a sort of adjustable "Mitre-box") does not as yet enable me to insure bisection on the middle line exactly, I have not felt justified in comparing the two halves of brains together. If both hemispheres are to be preserved entire, the section should go rather to the left than the right of the middle line, in order to leave the mesial sur- face of the right hemisphere uninjured ; but if the right is to be * This and the other figures will be found at the end of next paper. fThe extent of this loss may be seen from the following cases; a brain weighing ,065. lost one-sixth of its weight in eighteen hours, and one-third in four days; a brain weighing ,125. lost one twenty-fifth in sixteen hours and one-half its weight in two months; of course the rapidity of the loss will vary with the size of the brain, the amount and strength of the spirit and the frequency of its renewal. 218 B. NATURAL HISTORY. dissected, then the mesial surface of the left should be saved by carrying the section a little to the right ; of course, however, if there is certainty of the saw going just between the two, so much •the better. The pia mater should be removed before drawing; this is best accomplished after the brain has shrunken a little in spirit, using a pair of fine forceps and fine curved scissors. If possible, both sides of a brain should be drawn ; but if only one, the left ; and with all Carnivora (although not with all Her- bivora), all the outer fissures may be seen in such a view; while this is not the case in the view from above, even when the brain is flattened. In drawing, each half should rest upon a slip ruled in square centimetres ;* if the brain is larger than that of a cat, the slip may be pinned upon a sheet of cork, and two or more threads stretched over the brain, coinciding with the lines hidden by it ; then the drawing may be made upon another ruled slip, with great accuracy ; the mesial, upper and lower surfaces of the brain may be drawn in like manner, though less easily ; and large diagrams may be accurately reproduced, by ruling cloth in squares ten, fif- teen or twenty times the diameter of the original drawing ; the homologous fissures may be uniformly colored as in the diagrams exhibited ; Gratiolet, Owen and Bischoff have colored homologous folds, but it is obvious that the same end is more readily attained by coloring the fissures ; and that alterations are also more prac- ticable.' It would certainly be an advantage to possess a cast of the cra- nial cavity for comparison with the brain ; and all comparative measurements and weights should take into account the shrinkage of brains, and their loss of weight. f *I am happy to state that Mr. Geo. Woolworth Colton, the well known map-maker, and a member of this Association, has offered to prepare ruled paper of a size and quality suited to this and other natural history purposes. It will be noted that the perspective is ignored in drawings made by the above method ; each fissuie is represented as if at a point on a line perpendicular to the surface on which the brain rests: a drawing in which this line should be perpendicular to the convex surface of the hemisphere would produce the effect seen in fig. 5, plate la. f When a brain is once thoroughly hardened in alcohol it maybe kept in weaker spirit or clear water during examination ; it rapidly shrinks still more in the air; I am conducting experiments to show how well and how long, hardened brains can be pre- served in a mixture of equal parts glycerine and water; which does not evaporate like spirit and, by its greater specilic gravity, avoids injurious pressure of the specimens upon each other or upon the vessel; the best way of keeping many brains for study is in a wide tin box two or three inches deep and cased in wood, with a glass cover; if each half of a brain is kept on its mesial surface, no injury can result. B. NATURAL HISTORY. 219 The Cerebral Fissures. — More attention has been given to the folds (g3rri, convolutions, or anfractuosities) than to the fis- sures (furrows or sulci). But, whatever may be the manner of their formation, the latter really represent the location of the augmented gray, ganglionic or dynamic tissue more than the for- mer ; for, as a rule (the only exceptions being the points of oblique junction of two fissures), the contiguous walls of a fissure are nearer together than the two sides of either of the folds which it separates ; a line representing the fissure, therefore, indicates the location of a much larger bulk of gray matter than a line of equal width representing any part of the surface of the fold. Practically too the fissures are by much the easier to describe and designate, and it would be as hard to designate folds without first identifying fissures as to describe the countries of Europe without mentioning its rivers. The sides of a fissure are usually near together and parallel, so that the fissure may be described or figured as a single line of certain direction ; but the opposite borders of any one fold are rarely parallel throughout their whole extent. Moreover, the surface, which in one brain forms two folds, with an intervening fissure, may in another be one continuous fold. "What shall it be called ? Relatively, at least, the surface of a con- voluted brain is the same as it was before the fissures appeared ; while the fissures are gradually introduced and are to a certain extent capable of identification ; and although they may be wholly due to a vertical elevation of the contiguous folds, yet it is the fissures and not the folds which can be said to increase, to connect, or to remain separate. Granting, then, that folds are the ulti- mate object of our study, fissures are first to be so thoroughly identified in all animals that when one of them or one of the folds is mentioned, there can be no doubt of its being recognized by all. Fissures may be studied in four ways : First: As to their general nature. Second : Singly, as to their special peculiarities. Third : As evidences of zoological affinities. Fourth : As indications of intellectual power. The last view will be considered in the next paper. According to the first view, we may at once separate three of Owen's fissures from the rest. The rhinal is the line of separation between the olfactory crus or tract and the cerebrum proper. The median or 220 B. NATURAL HISTORY. inter-hemispJieral fissure divides the two cerebral hemispheres ; and although in most Carnivora the true fissures seem to be ar- ranged with some reference to it, and although it has clearly defined borders, yet neither of these features exists with Herbivora. The sylvian fissure marks the location of a kind of mound of cerebral substance, the "Island of Reil," and its manner of formation is somewhat peculiar, as shown hereafter. •Formation of Fissures. — No one doubts that all brains, even the most deeply furrowed, were smooth at an earlier stage of development. This transformation, so far as the result is con- cerned, might be compared with the segmentation of an undivided yolk ; but probably the process is more often comparable with the formation of the primitive furrow ; and although they look like clefts or depressions in the brain mass, it is probable that the fissures are the result of a difference in the rapidity of growth of different parts ; certain points or lines remaining relatively sta- tionary, and becoming the bottoms of depressions or fissures. Still I cannot rid myself wholly of the idea that shallow fissures, at least, may be formed by direct depression; and if Ecker is rightly ti-anslated he seems to have this view respecting all of them ; "Actual convolutions are formed in these districts only with the further progress of the formation of fissures (p. 14). The formation of the convolutions is, of course, entirely depend- ent on the development of the fissures ; and in the region of the temporal lobe, in which the latter are most variable, the convolu- tions are so too" (p. 65). But on page fifteen, in contrasting the sylvian with other fissures he says that the latter "originate simply from depressions or folds of the cerebral cortex." (The italics are mine). Now, as regards the aspect of the cerebral surface in the adult, it makes perhaps no great difference whether we speak of the fis- sures as depressions or the folds as elevations ; and the former is more natural on account of the greater extent of the elevated sur- faces ; so too in conversation it is easier to sa}r that the sun rises and sets than that the earth revolves upon its orbit ; but in sci- entific language it would seem proper to speak according to the fact rather than the appearance. Undoubtedly one source of confusion is the indiscriminate use of terms signifying the transformations themselves and the condi- B. NATURAL HISTORY. 221 tions reached thereb}' ; and we might avoid it by discriminating between appearance and aspect, formation and conformation, development and presence or existence, etc. As a single example of the looseness of our present expressions, on account of lack of definite information, Huxley (Comp. Anat. of Vertebrates, p. 492) enumerates among the distinctive features of the human brain, "the filling up of the occipito tempo- ral fissure," as compared with that of apes ; in its most literal sense this would imply that something filled a previously existing fissure ; a little less literally, that the bottom of the fissure grew up to the surface of the adjoining folds, so that a fcetal fissure did not exist in the adult ; and still again, and this would be a per- fectly legitimate interpretation, it might indicate the fact, that a fissure which exists in apes did not exist in man in any stage ; but even this would be capable of at least two meanings, according as the readers believed, or not, in actual evolution. The formation of fissures seems to proceed very rapidly.* I have traced it in kittens of the same litter, killed at short intervals beginning at birth ; and even allowing for individual and sexual differences, it would appear that during the first week, a change may occur perceptible within six hours ; the most favorable fissure for this purpose is the frontal. The large superficial cerebral vessels often lie in the fissures ; but that this is merely a coincidence, and not a cause, is indicated by the frequent departure of these blood-pipes from their trenches ; the slight furrow which marks the course of a large vessel across a fold has generally a more regular form with better defined bor- ders. Where the folds are much contorted as in man and most herbivora, as compared with their simplicity at an earlier stage, one can hardly avoid the conjecture that the folds are formed under pressure, and that the brain behaves much as would a piece of thick cloth crowded into a cavity. Still more suggestive of this idea is the lateral contortion of the median lobe of the cere- bellum in cats ; in the newly born kitten (Fig. 2, K), this is ver- tical in direction and presents few folds ; in all but one of the adult cats that [ have examined, the median lobe appears, as in Fig. 2, C, laterally contorted ; the progress of these remarkable changes will be fully illustrated on another occasion. f * As does the yolk segmentation with Turtles (Agassiz, Cont. Nat. Hist. U.S. 2, 523). fEcker speaks (p. 10) of the "formation of convolutions as a necessary consequence of certain mechanical processes of the brain and skull," but it is not clear how much influence is attributed to the latter by this expression. 222 B. NATURAL HISTORY. Yet while we may recognize a sort of correlation between the existence of fissures and the need of enclosing a certain amount of gray matter within a space which is represented by the cranial cavity, it by no means follows that osseous walls are the imme- diate and direct cause of the convolution ; much less does it follow that the particular direction of the fissures is occasioned by the ridges upon the inner cranial surface with which they coincide. In short, we may regard the size of skull and of brain as concomi- tants of the degree and character of fissuration without attempting, as yet, to assign to them the relation of cause and effect. It may not be proper to compare cerebral fissuration with the primitive formation of the encephalic lobes, but it is certain that this latter takes place independently of cranial circumscription, especially in many fishes where the cranial cavity far exceeds the brain mass ; and it would be interesting to ascertain whether this interspace exists in any of those fishes which, like Elacate, present some cere- bral fissuration. At present the matter must be regarded as un- decided ; and the way to elucidate our own lack of information is to ask ourselves whether, in total absence of cranial walls, any cerebral convolution would be developed in the higher Mammalia. Fissural Homologies. — In order to describe the variations of fissures in different brains, they must first be identified. Although Owen has (Comp. Anat. of Vertebrates, vol. iii, pp. 114 to 143) undertaken to homologize the fissures of the higher mammalia (Gyrencephala) throughout, and has rarely admitted the liability of error (as on p. 117), yet the very completeness of his determi- nations throws doubt upon them in view of the lack of reference to individual peculiarities, and the renunciation of development as a guide to homology ; and it will be safer to keep in view the con- clusion of Gratiolet. (Mem. sur les plis cerebraux de l'homme, p. 10.) " It is sufficient to compare the brain of an ape with that of a carnivore or ruminant in order to show that in the different mammalian orders, the cerebral folds present very different arrangements. These differences are such that it would be imprudent to establish par- allel divisions and to search for homologies. In fact that search has no certain basis, and we do not hope to accomplish it in a moment." Criteria of homology. — Having no true structural features, they present, as tests of homology: 1. Position in relation to B. NATURAL HISTORY. 223 internal structure (as the rhinal and sylvian). 2. Position in relation to other fissures so determined. In connection with this latter test, we must ascertain whether anything like transposition is possible ; this question will be raised in respect to special fis- sures. Their connections, branches, length, and general direction are probably of less value. Great aid is always to be had by comparison with simpler brains of allied species, or with the brains of young of the same species. The extent of variation in length, direction and connections, which may exist without invalidating their homology, is most readily seen by comparing the corres- ponding fissures upon the two halves of one brain (plate 3, figs. 12, 13) ; it appears that a long fissure may be represented by several short and disconnected ones ; that branches may or may not exist at either end (these branches are almost invariably dichotomous) ; that two fissures wholly separate in the foetus, and in other species may unite either directly or by a branch. Good examples of this are the lateral and coronal fissures, which are perfectly distinct in the foetus in some adults, and on one side only of others, but which show a tendency to unite ; a marked con- stancy in the location and direction of a branch may, as in this case, indicate the point of union. Finally, with respect to several fissures, we must either deny a homology which would be other- wise unquestioned, or admit that in one species or on one side, its manner of formation may greatly differ. This will be exemplified in connection with the special fissures in this and the following paper ; for example the presylvian, and the ectosylvian. While insisting, however, upon the provisional nature of many of the names which authors have given to the cerebral fissures of mam- mals, it is necessary to adopt some nomenclature in order to be understood, and in the present paper the names given by Owen will be employed with some modifications. Special Fissures. The Sylvian. — This is the most constant of all fissures ; there is no question respecting its existence or its name in all brains which are fissured at all.* Its length, direction, branches and connections vary consider- * On this account I have not hesitated to mark this Assure upon all the figures, s; but since there is some doubt respecting the name or the nature of all other fissures, the letters designating them are placed outside of the figure, in order to allow revision ; most of the figures are shown white on a dark ground; this will allow futuie alteration in the relative width of fissures in order to indicate their depth or relative constancy. 224 B. NATURAL HISTORY. ably, but, as a rule, in the adult it forms a nearly straight fissure directed dorsad and backward, never reaching the dorsal margin of the hemisphere, and rarely if ever inclining forward, though gener- ally nearly vertical in Herbivora. Its manner of formation is very peculiar, and may be readily traced in new born or foetal kittens and puppies; in these and also in the foetal wolf (fig. 6), there appears, where in the adult the sylvian is to join the rhinal, a rounded elevation (which is probably homologous with the Insula or Island of Reil, of anthropotonry) bounded above and behind by a shallow trench ; in front this island is apparently continuous with a narrow area of cerebral substance which still more anteriorly broadens into that part which lies just behind the olfactory lobe ;• the primitive sylvian fissure is therefore an cc-shaped depressed line whose posterior end joins the rhinal, and whose anterior end is turned upward ; by the gradual projection of the cerebral mass above this line, it overhangs the depressed tract, so that the ven- tral part of the curve reaches the rhinal fissure and coincides with it for a certain distance ; this portion I have ventured to call the basisylvian (Bs) ; by the growth of the mass before and behind the semicircular area now left, and the final approximation of the walls, the Insula is at length wholly concealed, and the semicir- cular trench becomes a single fissure ; strictly speaking therefore, the sylvian is an arched fissure like those which surround it {ecto- sylvian, supersylvian and lateral).* ' Presylvian (Ps.). — The anterior and ascending (dorsad) extrem- ity of the primitive sylvian seems to correspond with the "ascending *From a translation (Cerebral Convolutions of Man) which has just come into my hands, I find that Ecker of Freiburg, four years ago, observed the formation of the sylvian fissure, and that some of his conclusions upon this and other points are nearly like my own. I am sure that Ecker will be only glad that another has reached similar results from different materials, for he employed human brains exclusively, while I have purposely discarded them for the simpler brains of Camicora. Certainly he and all other honorable scientific men would accept the collections and drawings made by me as evidence of my entire independence in the work; but for the satisfaction of others, including the writer of an editorial in " The New York Evening Post" for Aug- 30, which directly charges me with unacknowledged borrowing from Ecker, I am com- pelled to state that to-day, Sept. 8, 1873, for the first time, have I learned the contents of Ecker's work. Moreover, while not questioning the correctness of Ecker's statement that in man " the whole hemisphere curves itself in an arch, concave below, around the place of eh. trance of the cerebral peduncle " (p. 15), it is proper to say that the brains of kittens and puppies examined by me do not confirm it; nor is it easy to see how so long a fissure as that of the bear could be formed in that way; it is evident that for the elucidation of this and many other points, we need a very extended series of observations upon the developing brain of many animals. B. NATURAL HISTORY. 225 branch" (Ecker, fig. 1, S") in its manner of formation, and in its relation to the sylvian; but the intervening space in all brains I have examined is so much larger than the "operculum" of anthropotomy that I hesitate to affirm it before observing its forma- tion in many intermediate species. Moreover, in a lion (fig. 18), there is a small fissure between the sylvian and what I take to be the presylvian, which in some respects more nearly resembles the "ascending branch" in man ; while in a bear (fig. 10) and raccoon (fig. 11) there is a similar one in front of the presylvian, which may be only a continuation of the slight upward curve at this point which the rhinal presents in many dogs. I would suggest the name presylvian, at least for the fissure already described in Car- nivora. It is evidently the same which Flower refers to as super- orbital (Anat. of Proteles; Proc. Zool. Soc, 1869, p. 479), but there seem good reasons for regarding it as ideally, at least, a dismem- berment of the sylvian. I say ideally, for although generally so in fact, yet occasionally there is no connection whatever, and that which would in respect to position be called presylvian is an isolated fissure. This is the case on both sides of a raccoon (fig. 11),* and on the left of an impure tan terrier clog; of the right of this brain I have no drawing, but think the union is as usual. This is certainly a point which should be clearly under- stood before we can be sure of the value of our determination ; at present I am not prepared to explain it. It will be noted also that in most dogs and in the lion, the presylvian is not only very long, but apparently double, as if a special and independent fissure had become connected with its dorsal end ; whether this is the case can probably be decided by sections, for there is reason to think that an independent fissure is always deepest at its middle where it may generally be supposed to commence ; and if the fissure in question is shallower at the point of suspected junction we may fairly conclude that it is really a compound fissure. Frontal! (F.)« This fissure is very characteristic of Carnivora, being absent, so far as I know, only in Paradoxurus figured by Gervais. (Nouv. Arch, du Museum, tome vi, pi. 9, fig. 2.) *But in another specimen the connection seems to exist as usual. 1 1 have adopted Owen's name as applied originally to the brain of cat and cheetah; but am not sure that it is homologous with that so called by him in the human brain. Flower has called it crucial. P. Z. S., p. 479. A. A. A. S. VOL. XXII. B. (15) 226 B. NATURAL HISTORY. The frontal appears from without as a cleft in the mesial mar- gin ; in kittens it begins as a mere shallow depression which rapidly deepens and narrows ; it is nearly as much a mesial as an outer fissure, and in some cases joins one of the mesial fissures so as to appear a continuation of it ; as seen from above the frontal extends outward and sometimes forward (as in fox). As a whole I have seen it take a backward course, only in a black bear, both sides, and a skye terrier, right side, although when curved, its outer end may turn slightly backward. It rarely branches, or if so but very slightly as on the right of a St. Bernard (524) ; in some cases, as in right of bull terrier (514) ; an apparent bifurcation is merely the union with it of a small secondary fissure. But even such junction is very rare ; on right of bear (502, fig. 10), it joins another at right angles, but on left a considerable space intervenes. Supersylvian (Ss.). Next in independence, in constancy, and in order of formation seems to come that semicircular fissure which Owen calls supersylvian ; perhaps it should precede the frontal in the above respects, but like so many other points, my present ma- terial (toes not enable me to determine this. I am quite certain, however, that Owen's table (C. A. V., iii, p. 136) does not in all respects (as its author admits) represent the relative rank of all the cerebral fissures. It generally divides the surface of the hem- isphere into two subequal portions ; its usual relation to the other fissures is seen in the fox (fig. 3) and the foetal wolf (fig. 6). In this, it forms a nearly regular curve with no branches or connections ; and whichever we may conclude to be its representa- tive, in the young terrier (fig. 7) it would appear to begin as a longitudinal groove about midway of its final extent and nearly over the sylvian. This is also the case in cats ; but in most brains its hinder end either branches or joins some small fissure, while, as a rule, its anterior end bifurcates, the longer arm reaching forward and ventral often with a slight dorsal turn at the extremity, while the shorter points obliquely forward and dorsal and often enters the lateral fissure just outside (as in Jrysena, fig. 9). This little branch so closely resembles the one which is given off at the junc- tion of the lateral and coronal in nearly all cases as to suggest that it is, like it, due to a union of two independent fissures ; but of this there is no evidence. The fact that a similar branch some- B. NATURAL HISTORY. 227 times leaves the ectosylvian, as in fox (figs. 3 and 4), suggests a like constitution for this latter fissure, or else a serial arrangement of cerebral foldings which is not as yet accounted for upon any theory of correlation between mind and brain. In a lion (fig. 18) the Ss is irregular, with branches and junc- tions with other fissures. In a bear (fig. 10) and raccoon (fig. 11) we have a peculiar arrangement, the explanation of which I for- bear to suggest until I see foetal brains of these species. The weasel presents only two fissures where most Carnivora have three, and it is not easy to say which they are ; a similar doubt is ad- mitted by Owen (C. A. V., iii, p. 117) in comparing the brain of Coati (JSfasua) with that of the stoat ; and I ask no better evi- dence of the fact that our knowledge of the zoological value of fissures is #s yet incomplete than the comparison between my fig- ure of the weasel's brain (fig. 8) and Owen's figure of the stoat's ; for the animals are similar species of closely allied genera, if not, indeed, members of the same genus (Allen, Bull. Mus. Comp. Zool., No. 8, p. 167), or varieties of the same species (Gray, Proc. Zool. Soc, 1865) ; yet my figure shows two fissures outside of the syl- vian, while Owen's has but one which he calls supersylvian. Lateral (L.). This is usually a curved furrow which divides the space between the mesial border and the supersylvian into two nearly equal parts.* The name was given by Owen, probably in reference to its approximate parallelism with the mesial border, which is often quite striking, as in the lion and hyaena ; but its anterior extremity is inclined to connect with another fissure, the coronal, so constantly and so smoothly that but for occasional ex- ceptions and observations of foetal brains, one. would incline to regard the whole as a single fissure with a branch, mesiad, resem- bling that of the supersylvian ; but a careful comparison indicates that the lateral generally bifurcates anteriorly, and that the ventral arm is joined bythe coronal; occasionally they miss connection, as on left side of terrier (fig. 12), shepherd (512), and of another small clog (540), on right of pointer-shepherd (fig. 14), and on both sides of skye terrier (503) and young tan terrier (534), on *This division of the cerebral surface into subequal areas by the fissures will be mentioned in the next paper; of course, as the hemisphere is convex, no figure can represent the true relative distances of the fissures unless the surface is projected upon a plane (as is done with a fox's brain, fig. 5) ; it would appear, however, upon a series of transverse sections, which I hope to show upon another occasion. 228 B. NATURAL HISTORY. left side of lion, and in cats generally ; the weasel has no coronal ; the bear and raccoon are peculiar in this as in other respects. In the young terrier (fig. 7) the lateral is very short and the union has not taken place. The Coronal (C) may be passed over with what has been said in connection with the lateral. But there are two secondary fissures which are associated with the hinder end of the lateral; one of them, which generally occurs in cats, has been called medttateral by Owen ; it lies mesiad of and usually behind the lateral and often joins it, but seems to be an independent fissure. When there is any fissure mesiad of the lateral in dogs, it lies farther forward, and is generally interrupted, so that I am not certain of the homology ; but in some cats (fig. 15) the true medi- lateral seems to coexist with an anterior fissure mesiad of the lat- eral; while in some dogs, greyhound (fig. 16), the lateral is prolonged backward, as if by a medilateral, while a separate fis- sure, apparently a true Ml, lies between it and the mesial border, and another, El, lies outside between it and the super sylvian. This last, which has not so far as I know received a name, may be called the ectolateral. Flower evidently alludes to its constancy in Canidoe (P. Z. S., p. 482), as occasioning the bifurcation of the posterior limb of the third gyrus (the value of his general- ization will be discussed farther on). Ectosylvian (Es.). This fissure is in some respects the most pe- culiar of all, for it presents differences not only of adult condition, but also of manner of formation, which lead us to doubt the value of this character. Its simplest, and what may be regarded as its normal, aspect is presented in the young terrier and foetal wolf, and in the adult fox, where it forms a curved line of greater or less ex- tent between the sylvian and the sitpersylvian (it is probably want- ing in the weasel, fig. 8) ; this regular form occurs also in some dogs, as a setter (10) (left side), and St. Bernard (524) (right), where, however, there are two or more small offshoots from the convexity, like the single and apparently normal anterior one of the fox ; but while the above instances would suggest that the ectosylvian is a simple arched fissure commencing at a point just above the tip of the sylvian, and increasing at both ends, many others would incline us to describe it as composed of three independent pieces, one in front, and one behind the sylvian, and the third connecting those above it ; as, for example, in the terrier (fig. 25). B. NATURAL HISTORY. 229 And that this is a not impossible view of its formation is shown by the fact that in several clogs, as right terrier (511) (fig. 13), and left greyhound (fig. 16) and St. Bernard, this top piece is apparently wanting altogether, leaving the front and hind posts of the door unconnected. This is apparently the normal con- dition of things in all Felidm (fig. 17), although the ends may branch, and, even as in lion, join other fissures. In many dogs, as the Pomeranian (fig. 20), the posterior upright may be in great part wanting, or abbreviated and joined with the sylvian; finally, in Hyazna (fig. 9), the anterior upright seems to be transferred behind the sylvian; but this involves a very grave general question of homology which there is no means of solving at present. It will be understood that the foregoing are by no means offered as full accounts of the outer fissures, even with respect to my present materials ; but rather as hints for monographic work upon them when a larger number of specimens or accurate drawings shall be available. Let me suggest in this connection, however, that to be useful, the original drawings should be made by the anat- omist, and that the transfers should be made under his eye ; an abbreviation or extension of a fissure, which would appear trifling to the most conscientious artist, might involve a contradiction of important generalizations respecting its connections. But before any final work can be done in respect to fissures, we need a complete account of the brain of some one mammal, giving its appearance from all sides, sections and dissections of all parts, and demonstrations of the relations which may exist between the fissural pattern and the internal structure ; then a full series of figures representing all the stages of development, both of the brain as a whole and of its parts ; on some accounts the fox would be the most useful species, but as it is not to be had in large numbers, and as dogs are ineligible as a standard, from the breed differences as well as from the usual complexity of the fis- sural pattern, we shall probably find the cat most available for this purpose ; such a work would form a fitting continuation of Straus-Durckheim's magnificent monograph of the Osteology and Myology of that animal.* Taxonomic Value of the Fissural Pattern. Upon this point Gratiolet speaks as follows (op. cit. p. iii) : — *It is one of the tasks which I wish to accomplish, but trust this will not deter others from undertaking it. 230 B. NATURAL HISTORY. "In like manner there is a particular type of cerebral folding in the makis, the bears, the cats, the dogs, etc. ; in short, in all the families of mammalia (d'animaux). Each of these has its own character, its norm, and in each of these groups the species can be easily combined according to the sole consideration of cerebral folds." Gervais* concludes that we may recognize order, family, genus and even species by the brain (Nouvelles Archives du Museum, 7, vi, p. 152). Flower says (op. cit. p. 480) : " For working out all the modifications of the brain convolutions of the Carnivora, a larger number of specimens would be required than are at present accessible ; but the series in the museum of the College of Surgeons is sufficiently extensive to show that they will furnish important indications of affinity, and that these indica- . tions correspond remarkably with the evidence afforded by the cranium, digestive and reproductive organs." While admitting the probability that such a family norm of fis- suration does exist and may hereafter be designated, yet the care- ful study of an amount of material greater in some respects, at least, than previous writers seem to have had, only makes me urge the importance of Gratiolet's remark, that " the value of any con- clusions respecting ideal unities has a necessary condition, that of resting upon a sufficient number of exact observations" (op. cit., p. iii) . The need of this may be seen by an examination of Flower's generalization, respecting the very groups which we can best illus- trate (op. cit. p. 482). "The dogs (Cynoidea = Canidce) are very uniform in their cerebral characters having always four distinct and regular gyri surrounding the fissure of Sylvius, which is short and approaching a vertical direction. The first and second arched gyri have the anterior and posterior limbs equal, the third has the posterior limb broad and bifurcated."! "All the other Carnivora have only three arched gyri on the outer surface, the first or lower one of the clogs being either wanting or concealed beneath the second within the fissure of sylvians. In the hyaena its hinder limb is partly exposed." "In the Arctoidai (=Ursidai, Procyonidm, Mustelidm, Ailuridm, *But although this author figures the brains of eighteen species of Carnivora (and casts of the cranial cavities of these and other species) he seems to ignore the existence of individual differences, and gives but a single brain for each species and none what- ever from dogs (excepting casts). tBy what I have called the ectosylvian fissure. B. NATURAL HISTORY. 231 Lutra and EnJiydra), the fissure of Sylvius is rather long and slopes backwards ; the inferior gyrus has the limbs long, corresponding with the length of the sylvian fissure ; the anterior rather narrower than the posterior (especially with the true bears) ; the middle gyrus is moderate and equal-limbed ; the upper one large, very broad in front and distinctly marked off from the second poste- riorly, as far as near the lower border of the temporal lobe ; except in the smaller members of the genus Mustela where the sulcus sep- arating the superior from the middle gyrus is less produced pos- teriorly than in others of the group. In Galictis vittata, however, the brain is quite a miniature of that of a bear ; but the middle convolution is united with the upper one at its superior anterior angle." " In the JEluroidea (including all other Carnivora excepting the Pinnepedia) , the sylvian fissure is moderate and nearer to the ver- tical than in the last group. The gyrus which immediately sur- rounds it is wide, especially the posterior limb which is generally twice the width of the anterior and is divided by a vertical fissure,* well marked in the cats and hyaenas. In the cats the anterior limb is also partially divided. In the civet both limbs are simple, the second gyrus is moderate and simple. The superior gyrus is wide in front but small posteriorly, the sulcus which separates it from the second not extending quite to the hinder apex of the hemisphere (the suricate agrees with the hyaenas rather than with the civets in the general character of its brain convolutions)." Of the Arctoidea, Prof. Flower may have had more material than I, but in the absence of exact enumeration, his characterization of the fissural pattern seems to me insufficient at least ; if by clogs, Prof. Flower includes only the feral Canidas, his generalization may be not far from correct ; although the backward slant of the sylvian, in both my own and Gervais' drawings, is generally greater than in hysena and weasel, and equal to that of cat and lion. But if the domestic dogs are included the definition would not apply to many of them ; for the bifurcation of the third gyrus is often so complete as to constitute two equal gyri, as on left of terrier (fig. 12), and the outer or fourth gyrus may be likewise bifurcated, as in left of greyhound (fig. 16), while the first and second gyri are, as a rule, rendered irregular by the peculiarities of the ectosylvian ; moreover, the generalization respecting all other * Which I helieve to he the hinder upright of the ectosylvian. 232 B. NATURAL HISTORY. Carnivora involves a denial of the homology of the complete ectosylvian of the fox with the incomplete one of the cat, yet this last is very nearly like those on the left of the terrier (fig. 12) and greyhound (fig. 16).* Other discrepancies might be pointed out, if it were possible to present, in this paper, figures of all the brains which I have pre- pared ; but so long as Prof. Flower makes no reference to the dif- ferences of individuals of the same species, to variations of age and sex, or to differences between the right and left sides of the same brain, I shall be obliged to doubt the value of the general- izations. Lateral Variation. I wish it had been possible to offer here drawings of both sides of all the brains of the feral, as well as domestic Carnivora. I do not recall a case in which this lateral variation has amounted to the total absence of a main fissure upon one side ; it consists rather in a difference of length, depth, branches and connection, or of nearness to other fissures ; the minor fissures, however, present very great lateral variations as to presence and location. Since most of the examples given are from domesticated dogs, I do not wish to lay too much stress upon the fact of lateral variation, but in no work have I seen both sides of an animal's brain figured or described ; and since no two brains of different species can be so nearly related as the two halves of the same brain, it is evident that a 'careful study of lateral variation will furnish a test of the value of the differences observed among brains (see plate 8). Lateral Compensation. Lateral variation is often compensa- tory. For instance, a long fissure of one side may be repre- sented by several short ones upon the other, the aggregate length being equal to the single one ; a straight fissure may represent a curved one ; or a single one may have as counterpart a shorter one with a branch ; in one case, the total length of a bifurcated sylvian fissure is just that of the longer but undivided fissure of the oppo- site side. * The foregoing certainly raises the question whether we can rightly look for tax- onornic assistance among the organs of domesticated animals: but meantime it seems proper to include our canine varieties in any generalization respecting the group of Cynoidea. B. NATURAL HISTORY. 233 The functional significance of this will be alluded to in the next paper. Conclusion. The' foregoing is far from a satisfactory view of the subject ; but it is all I can offer at present. My chief object has been to point out the defects of our methods of preparing and drawing brains, and the insufficiency of material for making any generalization respecting that mammalian order whose brains are' most readily obtained and whose fissural pattern is comparatively simple. "With a single specimen or figure of the brain of Felis, Canis, Hyc&na, Ursus, Mustela, one might make generalizations as to specific, generic and family fissural patterns which would be quite as true .to nature as many which are annually published upon this or other departments of Comparative Anatomy, but they might be controverted by other specimens or even by the other halves of the same. The greater complexity, both from secondary fissures and from contortions of the primary fissures^ which pre- vails with the brains of most Herbivora, is an a fortiori argument against making the attempt to determine their fissural patterns before the Carnivora are disposed of. After a pretty careful study of the specimens and works at my command, I feel justified in asserting that we cannot as yet characterize the fissural pattern of any mammalian order, family, genus or even species without the risk that the next specimen will invalidate our conclusion ; that our studies in this direction should be based upon the careful comparison of accurate drawings of a much larger number of spec- imens than now exist in any museum ; that nearly allied forms of Carnivora should be compared ; and that the most satisfactory results are obtainable from large series of foetal and young brains of the same species, and, if possible, family and sex, in order to eliminate minor differences. Addendum on the Lion's Brain. The kindness of Mr. Lee Powell* has just enabled me to prepare the brain of a young African lion, seven and one-half months old ; the left hem- isphere is here figured (fig. 19) for comparison with the Asiatic. The most striking difference is in the great development of the temporal lobe (the postsylvian region), which not only projects laterally more than in the other, but also forward over the region *0f Robinson's Circus and Menagerie, Utica, N. T. 234 B. NATURAL HISTOET. just in front, so as partly to cover it and make the ventral portion of the sylvian coincide with the ventral branch of the ectosylvian, (Es) ; the frontal region is less prominent, and the outline of the cerebellum is quite different. In the Asiatic lion the left coronal is wholly independent ; likewise the right coronal of the Af- rican ; but the right of the former joins the lateral, which is the usual arrangement, while the left of the latter joins the super syl- vian in a similar fashion. Other differences might be pointed out both between the two brains and the two halves of each ; but it seems to me that these alone are enough to make us hesitate from basing a diagram of the fissural pattern of this species upon any such number of specimens as are likely to be found in any museum ; while the same peculiarities present almost insuperable obstacles to a recognition of particular folds as organs of special mental faculties separated by certain fissures. [The figures illustrating this paper are given in the plates, be- tween pages 248 and 249, and their explanation will be found on page 249.] Cerebral Variation in Domestic Dogs, and its Bearing upon Scientific Phrenology. By Burt G. Wilder, of Ithaca, N. Y. The following observations are based upon the careful study of thirty-two dogs' brains, representing fifteen to twenty breeds. There were four of the same family, a mother and three children of different ages ; two others nearly related to them, and two pair of brothers of different ages ; the others are not known to be re- lated ; most of them are supposed to be of pure breeds.* ♦The figures referred to in this paper are included with those of the preceding paper in the plates placed between pages 248 and 219. B. NATURAL HISTORY. 235 LIST OP DOGS' BRAINS PREPARED AND DRAWN BY ME, AND FORMING THE MATERIAL UPON WHICH THIS PAPER IS BASED. M.C.Z.* No. Breed. Age. Sex Weight of Body, in grams. t Weight of Brain. i 03 o"o3 Fig. 1 Pomeranian, or Spitz. adult. ? 8,837. ,068 .007 20 3 2 4 " "1 children of | No. 1, by the " i> same father, 1 but of 2 sepa- " J rate litters. 5 weeks. 4.1 » 54 hrs. ? ? d 1,316. 1,006. ,132. ,047 ,041 ,008 .035 .010 .060 21 22 23 215 216 (( ") later children (of mother of (( {father above J mentioned. 3 days. 3 days. ¥ ? ,213. ,247. ,010 ,011 .047 .044 24 25 522 Eng. rat terrier (small blk. and tan). Eng, rat terrier brother of above. Spaniel % pure. at birth. 24 hours, at birth. ? ? ,092. ,081. ,221 ,005 ,008 ,007 .054 .099 .030 511 512 Eng. blk. and tan ter- rier (small). Shepherd. 6 mos. young. ¥ d 1,320. 1,952. ,038 ,055 .028 .028 12,13 540 Shep. cur (pt. terrier ?) 6 weeks. 9 2,228. ,058 .021 541 Mexican (Chihuahua). 17 years 8 mos. d 2,436. ,050 .020 6 7 Eng. terrier ~i > brothers. 9 mos. 3^ yrs. d d 5,300. 5,300. ,074 ,069 .014 .013 25 526 Italian greyhound. lyr. d 6,074. ,067 .011 8 Ital. greyh'nd impure. adult. d 4,367. ,065 .010 520 Spaniel (large impure). adult. d 6,158. ,062 .010 536 Chinese (hairless). 9 mos. d 7,026. ,074 .010 1 503 Skye terrier. 15 yrs. d 7,800. ,072 .009 578 Hound. 20 yrs. d 22,450. ,108 .005 9 Setter (large). 12 yrs. d 25,400. ,106 .004 Newfoundland. adult. d 38,315. ,120 .003 26 13 Bull and cur. 12 yrs. dt 40,570. ,125 .003 St. Bernard. With seven others the re old. cord of which is i 9 nore 40,820. or less im ,098 perfect. .002 25 No. 7 was not weighed; he was slighter in form than No. 6, but the weights are assumed to be equal ; the "fresh weight" of the brain is computed by forming a proportion with another brain *This is the number on the Catalogue of preparations of Domesticated Animals in the Museum Comp, Zool. t Castrated at about six years old. J For uniformity, a full stop is placed after the number of grams (the unit of weight), and a comma after the number of kilograms (1000 grams). 236 NATURAL HISTORY. of nearly equal weight when hardened, but the fresh weight of which was also known : as to the weight being greater than that of the older brother's brain, I can only adduce the greater mental and physical activity which it displayed. The brains of dogs are by no means common in museums, and figures of them are even more rare, partly, perhaps because the very commonness of the species induces delay in its examination,* but partly, I am inclined to think, from a notion that since they are all called dogs, there can be no great anatomical differences between them. Yet aside from any question of their origin from different specific forms of feral Caniclce, the fact is patent that our various breeds of dogs differ among themselves in respect to size, color, form and habit far more than would be required for the dis- crimination of species among wild animals ; and there have not been, so far as I am aware, any investigations to show whether., or not, these external distinctions coexist with structural peculiarities. It had long been my wish to undertake such an inquiry ; and the liberality of Prof. Agassiz, in authorizing me to make for the Museum of Comp. Zoology a collection to illustrate the neurology and embryology of . domesticated animals, has afforded me the means of commencing the investigation. The table of absolute weights of brain and its ratio in thou- sandths to the whole body is mainly confirmatory of the general rule that young mammals have proportionally larger brains, and that the smaller species and varieties in like manner excel the larger ; but the difference between, for instance, a little tan terrier and a Newfoundland is something prodigious, as seen by the fol- lowing selected table, where the large dogs are represented by the Newfoundland, the medium sized by the English terrier (common size) and the small and young clogs by the small terrier and young- est Pomeranian. No. Variety. Age. Body. Brain. Ratio. 4 Pomeranian. 54 hrs. ,132. ,008. .oco 8 Eng. terrier (small). G mos. 1,320.. ,038. .028 7 " " (large). 3| yrs. 5,300. ,089. .013 Newfoundland. adult. 38,345. ,120. .003 *As the house fly and mosquito are seldom among the first captures of the entomol- ogist. B. NATURAL HISTORY. 237 Generalizations like the above, and others which might be made respecting the ratios at different ages, in the two sexes and in various breeds, are evidently provisional until we have a much larger mass of material. I would add that measurements were taken of the intestines ; the capacity of the stomach and coecum was recorded and all viscera were weighed, so that I shall at some future day be able to present some statistics respecting them, and also respecting the degree of variation in the form of the stomach and coecum, of which many specimens are preserved, inflated, either at Ithaca or in Cambridge. This is the case also with all the other mammals here mentioned. TABLE SHOWING THE RATIO OF BRAIN AND BODY WEIGHTS OF A FEW MAMMALS, CHIEFLY CARNIVORA. 577 530 552 12 502 577 528 188 379 175 347 354 325 537 Scientific name. Macacus ? Vulpes fulvus. Canis lupus. Canis familiaris. Felis catus dom. Felis leo. HyEena vulgaris. Ursus America- nus. Procyon lotor. Putorius Nove- boracensis. Equus caballus. Bos taurus. Camelus bactria nus. Common name. White faced. Red fox. Gray wolf. See special table. See special table. African lion. Striped hyaena. Black bear. Raccoon. Weasel. Mare. u Horse. Colt. if Durham bull. Camel. Age. 5 yrs. adult. 4 days a. p. average of 6 adults. 7j mos. old. lyr. adult. nearly grown. 14 yrs. adult. adult. at term. ? 2 yrs. ? Weight of body. Brain Ratio. 2,939. ,082.5 .028 s 2,918. ,047. .016 ,460. ,009. .019 2,847. ,027. .009 c? 11,230. ,162. .014 ? 33,770. ,110. .003 X ,240. d 5,540. ,044. .OOS ,ioo: ,005. .050 ? ,684. 9 ,597. <3 ,580. d1 ,361. 15,938. ,190. .012 1 590,000. ,337. .0008 ? 299,813. ,615. .0025 P 5 .073 .117 .550 .040 1.247 In comparing the weight of the brain with that of the flexors of the lower jaw (temporals and masseters) we find, for instance, that 238 B. NATURAL HISTORY. the jaw muscles are about eight times heavier in a hyaena, four times in a Newfoundland, twice in a bear, a fox, and camel, but the same weight in a tan terrier, while in the young lion (552) they are only about two-thirds the weight of the brain, although this ratio must alter greatly as the animal grows older. TABLE OP TWENTY-THREE DOMESTIC CATS. M.C.Z. Variety. Age. Sex. Body. Brain. Ratio. 220 Common ?1 17 days. cf ,180. ,013. .072 219 " J- same litter. (C <$ ,262. ,013. .049 218 << J " 9 ,250. ,013. .052 222 « 5 days. ? ,128. ,018. .033 40 (i 3 clays. v ,080. ,004. .050 38 u at birth. 9 ,110. ,005.5 .050 39 " (sister of 37). 36 hrs. ? ,075. ,003.5 .047 37 << 12 hrs. d ,092. ,003.5 .038 542 Maltese. j cf ,560. .022.' .037 48 £< 23 days. cf ,359. ,014. .039 25 " (in part). ? 9 ,648. ,021.5 .033 24 .< a « 2 mos. 9 ,800. ,025. .031 34 Common. 3 days. 9 ,099. ,003. .030 510 Maltese (in part). ? ? ,963. ,023. .024 26 " ? ? 1,770. ,026. .015 32 Common. adult. 9 1,882. ,025. .013 " " cf 2,591. ,031. .012 20 " (striped gray). young. 9 1,912. ,023. .012 30 Common. ? 9 2,276. ,027. .012 23 (< adult. 9 2,370. ,028. .012 28 << " 9 2,978. ,027. .009 22 Maltese (in part). » cf 4,550. ,031. -007 21 (1 c< tc it cf 2,712. ,025. .007 The following inferences may be drawn, provisionally, from the foregoing table. 1. The ratio of brain to body, in the adult cat, is about the same as in the adult dogs of the medium sized breeds : namely, .007 to .015. B. NATURAL HISTORY. 239 2. In kittens of the same litter (as 218, 219, 220 and 37, 39) the brain weights are more uniform than the body weights, and the latter causes a variation in the ratio. 3. Although the increase of the body weight is much more rapid than that of brain weight, when the whole period of growth is con- sidered, yet a comparison of 38, 39, 37, 34 with 218, 219, 220, 222, 48, shows that the brain must grow very rapidly during the first two or three weeks after birth concomitantly with the increase in bodily powers and the use of the senses. A comparison of 2 and 4, among dogs, looks the same way ; and in both cats and clogs, it will be remembered that the forma- tion of fissures proceeds very rapidly during the earlier days. "With pigs, calves and colts, on the other hand, I have found the fissures already deep and numerous long before birth, and it will be interesting to contrast the relative increase of brain and body weights in the Carnivora and Primates which are born helpless, and the Herbivora, which are in fuller possession of their faculties at birth. General Form. — Some dogs' brains are high and rounded, while others are low, long and narrow in front ; of the latter type are those of setters, Newfoundlands (Fig. 26), St. Bernards, shepherds and bull dogs ; in all of these the olfactory lobes are visible for about half their extent when the brain is seen from above but they are wholly concealed by the hemispheres in the Pomeranians (Fig. 20), greyhound (Fig. 16) and terriers (black and tan, Fig 12), the Chinese and Chihauhau dogs ; and between the two groups come the bull terrier and skye terrier. In the fox and wolf the brain is narrow and low in front, but in the lion it is rather high ; while in the domestic cat, though low, the frontal region is very broad ; evidently, however, it is not easy to discriminate between the effect of large size of a certain region and the relatively small size of an adjoining one, and it must be remembered that in all very young dogs' brains the olfactory lobes are hidden, but this is probably from their own undeveloped con- dition. The greater prolongation of the olfactory lobes and of the ad- joining region of the cerebrum, in front of the presylvian, which generally prevails in the larger dogs at least, as compared with the Felidce, might be held to indicate their superior power of scent ; but this proves nothing respecting any mental faculty. 240 B. NATURAL HISTORY. M.C.Z. Animals. Fig. Length of Hemisphere in millimeters.* In front of frontal. Ratio. 13 Bull and Cur. .069, .023, .333 7 Tan terrier. 25 .053, .010, .188 14 Pointer and shepherd. 14 .045, .013, .288 Cat. 17 .032, .003, .094 510 Lion. 18 .071, .013, .183 The above table is in no way intended as an index of the zoo- logical or psychological relations of the several animals, but as a single proof of the impossibility of basing generalizations respect- ing groups upon one or even several individuals ; for in respect to an element of brain form which might naturally be noted in anj' attempt at characterization, there is nearly as much difference between two dog varieties as between two Feline species, or be- tween the cat and the terrier. Fissural Complexity. — There must be, of course, a limit to the depth of fissures (or to the elevation of folds), although we have, as yet, no means of ascertaining the nature of the limitation, nor whether it is uniform in all brains ; but supposing it to be equal in two given cases, it is evident that a larger number, or length, whether of branches or secondary fissures, indicates a cor- respondingly larger amount of gray matter ; and this, supposing its quality to be equal in the two cases, indicates a greater amount of brain power. 1. Now the cerebral mass is capable of expending nerve force in three directions, which are ideally distinct, at least in their purpose, but practically linked together in most cases. 1. Physical, lfor the individual. 2. Mental, ) 3. Sexual, for the species. At present we have no way of ascertaining from the brain alone , whether its peculiarities relate to greater mental, physical, or sexual power. We would naturally account for the more numerous fissures of dogs, as compared with the feral Canidce, upon the ground of *A full stop is placed after the place for the number of meters (the unit of measure), and a comma after the millimeters (thousandths of a meter.) * B. NATURAL HISTORY. 241 their higher mental capacity ; and upon this ground must be ex- plained the somewhat remarkable fact that the brain of an adult Pomeranian female (Fig. 20) has fewer fissures than that of her five weeks old pup (Fig. 21) ; for the father was a trained dog, while the mother was comparatively unintelligent. But the wolf, according to Gervais' figure, has more secondary fissures than the fox, and this must be accounted for .by its greater physical power. Perhaps this is also the explanation of the great fissural com- plexity of the young lion, as compared with the adult cats or even most dogs ; but Professor Agassiz has suggested to me that the greater power indicated by the condition of the lion's cerebrum may be connected with its prodigious' virility, the complete sexual act having been performed nine times in an hour, under his obser- vation, and the same rate having been maintained during at least two successive nights. In a young lion's brain (Fig. 19) the depth of the super sylvian fissure is at least one-half the thickness of the hemisphere at that point and in its plane ; while in an adult cat's brain the depth was only one-fourth, and in a dog's about one-third ; all the other fissures were very deep in the lion, and the layer of gray matter very thick. I hope to make a careful measurement of several dog's brains, according to the method adopted by Wagner, with such suggestive results. 2. There are individual variations among the adults which do not affect the presence or relative position of main fissures, but their length, direction, branches, connections and continuity, and, by inference, the manner of their formation ; these variations enable us to recognize any brain and may in some cases approxi- mate them to other carnivorous families.* 3. The two sides of the same brain present just such variations as those above described between different individuals. The few instances cited show to what extent this variation may exist ; so great is it, indeed, that I do not think it possible to "mate" two hemispheres by their fissural pattern alone, without taking into account the similarity of size, or general form. * The resemblance of the ectosylvian fissure of certain, dogs to that of the cats is re- ferred to in the preceding paper. The number of specimens is not yet large enough to justify any inference respect- ing the sexual peculiarities of brains. A. A. A. S. VOL. XXII. B. (16) 242 B. NATURAL HISTORY. % 4. There are resemblances between brains of the same breed, which lead ns to suspect the existence of a uniform modification of the general pattern for different breeds. This is noticeable in the Pomeranian series ; but in the first place some other brains show the same tendency of the ectosylvian to join the sylvian, and in the second place the near relation- ship of all the younger dogs to the single adult prevents our knowing how far the resemblance is one of family and how far of breed, in general. The same doubt exists respecting two tan terrier brothers (6 and 7) whose brains are similar, especially since they do not particularly resemble those of others of the same breed. 5. All of these dogs' brains are comparable in respect to the fissural pattern, both among themselves and with the feral Caniclce. There is something which leads even the child to call all dogs by that name, whether they be terriers or kSt. Bernards, grey- hounds or bull-dogs, poodles or mastiffs ; just what this feature is, has not, so far as I am aware, been scientifically described ; nor have I any suggestion to make ; the case seems to be similar with their brains ; I do not think I should mistake the brain of a dog for that of any other animal, but I cannot yet say upon what grounds, and am by no means sure that my diagnosis would be correct in all cases. But it is evident that in order to ascertain whether or not there is any peculiar dog pattern, and if so, what it is, a much greater amount of material is required than is now accessible. If nothing else, I have at least shown that no fissural pattern involving several fissures can be correctly known from the exam- ination of a single brain, much less one side of such brain. The collection at Cambridge is very large as compared with that of most museums, but far too small for any final conclusions. I merely venture to express the hope that when we are able to com- pare say twenty-five brains of the same breed of dog, we may be reasonably sure what are its cerebral characteristics, and prob- ably several hundred specimens will be required to demonstrate the essential features of the dog's fissural pattern as contradis- tinguished from all other Caniclce. The immense cost of such a collection raises the question of the value of the result, and this is only part of a general question not sufficiently considered when scientific inquiries are begun. B. NATURAL HISTORY. 243 If a tiling is to be done at all, it can be accomplished far more completely and economically by one person or one institution than by several working separately or at different periods. I would therefore ask members of the Association to bear me in mind when they have or know of a dog of pure blood and well known character, which has outlived its usefulness ; a careful transportation and death by chloroform will obviate distress on the part of both the animal and its master. The relation of these variations to Scientific Phrenol- ogy.*— In using the phrase " scientific phrenology" I place myself between two fires ; for the professional phrenologist claims that all phrenology is scientific, while many scientists deny the com- patibility of the terms. Let it be understood then, that I use phrenology in a general sense, and to avoid coining a new word, to indicate the study of the brain as an organ of the mind ; and, further, that I am not in the least biased by the views of others, but am trying to learn the truth by a new method of investiga- tion. In justice to »myself also, it is right to state that I speak as an anatomist and not as a physiologist, much less as a psy- chologist. With all due respect for the latter classes of investi- gators, I believe that they have* been hitherto building upon very slight foundations, and that an immense deal of hard work in the way of anatomical comparison must be done before they can be sure of the grounds upon which their experiments and conclusions can be based. Further, I hold that most of the facts already at hand are not of the right sort ; and that we have begun at the wrong end and in the wrong way in our efforts to correlate brain and mind. Mental associations of parts of the Brain mass. — Four methods may be employed in order to ascertain the mental associ- ations of parts of the brain mass : 1. The Phrenological. The skull was accepted as an index of the form of the brain, and a certain number of cases of corres- pondence between cranial forms and marked characters was held to demonstrate the locality of mental faculties and propensities. *This phrase is used by Gervais (Nouvelles Archives du Museum, tome vi, PI. 9, Fig. 2). This author gives admirable lithographs of many brains and moulds of the cranial cavity, and suggests the value of a comparison of carnivorous brains, for the advancement of " scientific phrenology." 244 B. NATURAL HISTORY. That this method is not satisfactory appears from the following considerations. a. No definite and constant correspondence whatever exists be- tween folds and fissures of the brain and the outer cranial surface. b. Several important faculties are located over the frontal air sinuses, as pointed out by Dr. Clelancl, from whom the accom- panying figure (Fig. 27) is copied.* . 232.) Fig. Hi. Greyhound, one year, J (526.) (p. 2290 Lions. Plate 4. Ss El? Ss Ps Bs X Fig. 18. Lion. Felis Leo, var. Asiaticus: seventeen months. Cerebellar lobes shown in part. (510.) p. 233. Ss'? L Es Fig. 18. Lion. Felis Leo, var. Africnntts, <$ seven and one-half months. Cerebellum in outline only. (552.) p. 233. Plate 5. Varieties of Dogs. Es Ss L Fig. 20. Pomeranian dog, $ adult (1). (Mother of 21, 32, 23.) Ss' El Ml? Ss L Es' Fig. 21. Pomeranian pup, 2 five weeks. (3) L Es SsE ?M ? Fig. 23. Pomeraaiau pup, fifty-four hours. (4) Fig. 25. English terrier, oil. lobe hidden ; three and one-half years. (7) (p. 22S.) Es Ss xc Fig. 24. (41 and 42) Pomeranian pups, 2 three days. Fig. 22. Pomeranian pup, 2 four and one-half weeks. (2) Er: Fig. 26. Newfoundland, cf adult. Olf. lobe exposed. Double Human Monster. Plate 6. o 2. B. NATURAL HISTORY. 249 All the facts indicate that while it is not impossible or even im- probable that different areas of the cerebral surface may be in functional relation to either movements or mental operations or both, yet these areas are not always, if ever, circumscribed by the fissures; that the fissures merely increase the amount of gray matter wherever they are ; their signification being rather quanti- tative than qualitative. This question might be decided by Dr/Ferrier's method, explor- ing not only the free surface of the folds but also the hidden walls of the fissures. Explanations of Figures.* — With two exceptions (Figs. 10 and 13) the brains are shown from the left side, and all the drawings are made from specimens hardened, and thereby shrunken, in spirit. The olfactory lobe is given in outline ; also the cerebellum and medulla oblongata : but neither the nerve roots, nor the cerebellar convolutions are indicated. As stated on page 218, note, each fissure is drawn as it appears to the eye placed over it perpendicularly to the surface on which the brain rests. Figures 3, 4, 20, 22, 25, showing the fissures dark on a white ground, have been kindly loaned to me by the " N. Y. Tribune," from those which illustrated the report of my lecture on "The Brain, and the present scientific aspect of Phrenology," printed in the "Tribune" Extra, No. 3 : a few inaccuracies which could hardly be avoided in the hasty preparation for the press, have been since corrected. The remaining figures, in which the fissures are shown white on a dark ground, have been drawn on wood and cut by Mr. Philip Barnard of Chicago (now a student in Cornell Univ.), to whose patience and accuracy I gladly bear witness. All the drawings were made by me from specimens which I had prepared. The fissures are lettered uniformly throughout. S— Sylvian. lis — Basisylvian. Ps— Presylvian. R — Rhinal. Er— Ectorhinal. F— Frontal. C — Coronal. Es— Ectosylvian. Es' — Its posterior branch. Esv — Its ventral branch. Ss — Supersyl vian. Ss' — Its medial branch. L — Lateral. L' — Its medial branch. El— Ectolateral. Ml — Mediluteral. * The numbers in parenthesis refer to the Catalogue of the Neurology and Embry- ology of Domesticated animals at the Museum of Comparative Zoology. A. A. A. S. VOL. XXII. B. (16*) 250 b. natural history. Lateral Asymmetry in the Brains of a Double Human Mon- ster. By Burt G. Wilder, of Ithaca, N. Y. [The figures form plate 6 at the end of the preceding paper.] It is generally known that the right and left hemispheres often present considerable differences in the details of the cerebral pat- tern ; but very rarely do we find figures or detailed descriptions which indicate the extent of this lateral variation, although its ex- istence would seem a serious difficulty in respect to phrenology. As remarked in a previous paper no brains of different individuals can be so closely allied as those of the same individual, and a study of these must serve to check our estimates of the zoological value of fissural variation between species ; next in value for this pur- pose would usually be ranked the brains of twins or, with animals, brothers and sisters of the same litter ; but an intermediate stage of relationship is presented by double monsters, like the one de* scribed in the next paper, and as their brains are rarely preserved or figured, I have thought them worth recording.* The brains were bisected soon after extraction ; each was weighed and each cerebral hemisphere placed in spirit upon its mesial surface ; being quite soft, they became unnaturally flattened vin the process ; they were drawn after hardening and the two right hemispheres shrank while drawing, from evaporation of the spirit, so as to lessen their area and to expose the island of Reil to an unnatural extent, as appears in figures 2 and 4. This prevents the otherwise interesting comparison of the four hemispheres in respect to the length of the fissures, without reference to their depth ; and in respect to the total area of the outer surface of the hemispheres. But the fissures themselves and their connections are unchanged, and certainly present some striking differences whether the two brains are compared together, or the two halves of the same brain. I have lettered only the sylvian (S'),its ascending branch (S"), the first temporal (f) ; and the fissure of Rolando or centralis (C). The temporal (f ) of the right brain, left hemisphere, is in two portions, the separation occurring at a point corresponding with a transverse fissure in the other hemisphere ; and although Ecker * I hope on a future occasion to present a detailed comparison of the four hemi- spheres of several double-headed calves and pigs, which are now in the Museum of the Cornell University. B. NATURAL HISTORY. 251 says nothing of it (op. cit. 62), yet some foetal brains in my pos- session indicate that there may here be two fissures which origi- nate separately but usually unite ; the case may be compared with that of the lateral and coronal in carnivora. (See page 227.) I do not feel sufficiently sure of the correctness of the generally received designations of the other fissures to compare them indi- vidually, but it is evident that all the fissures differ greatly as to length, direction, branches and connections, and that the smaller fissures vary considerably in number, giving an appearance of fis- sural complexity in the following order. 1. Left brain, left hem- isphere ; 2. Left brain, right hemisphere; 3. Right brain, right hemisphere ; 4. Right brain, left hemisphere. It is worth noting that, excepting with the left brain, right hem- isphere, this order is inversely to that of the weights, as if by way of compensation ; also that the two hemispheres of the left brain present the two extremes of fissural complexity, while the intermediate conditions are seen in the right brain. Furthermore, it may not be too much to associate the greater weight (,024. grams) of the whole left brain over the right, with the fact that the corresponding part of the double body is larger than the right, and the median third leg is thrown over toward the right side, as if it were more fully a right leg of the left child than a left leg of the right child. The combined weight of the two brains is ,768. which is to that of the bodies, 5,000. about as 1 to 64-, which is the average ratio in females at birth, according to Tiedeman ; that in the male being, according to the same authority as 1 to 5-85 ; as quoted in Quain's Human Anatomy, ii, 570. This monster is apparently of the male sex. The Papillary Representative of Two Arms of a Double Human Monster, with a Note on a Mummied Double Monster from Peru. By Burt G. Wilder, of Ithaca, N. Y. The double monster here referred to was still-born, at term, in March, 1873 ; aside from the malformation it was of good size and appearance ; the left spine was found to be fractured, and 252 B. NATURAL HISTORY. it may have died during parturition which was long and difficult, although the mother recovered without trouble. Having preserved all the viscera (including the brains, which were described in the previous paper), it is my intention to pre- pare a detailed account of the case in connection with several other double monsters in my possession, so I will merely men- tion that it weighed about 5,000. grams (about eleven pounds), and measured about twenty-two inches when the legs were extended. • There are two stomachs, symmetrically disposed, as usual in such cases ; the small intestines continue independently to near the csecum ; this, the colon and rectum are single, the latter ter- minating at an imperforate anus, just above (behind) the genitals ; there are two hearts, and two pairs of lungs ; four kidneys and two bladders ; the sex is apparently male, but the testes have not entered the scrotum, and I have not yet looked for them among the viscera. As seen in the figure, its heads are separate and complete, the right larger then the left, as with the corresponding brains ; the opposite limbs and sides of the compound body are some- what unsymmetrical, the right child seeming to constitute more than half of the whole ; the hands and feet are quite well formed but there is an extra right pollex ; further details will be given hereafter. So far this specimen nearly resembles that so well described and figured by Professor Jeffries Wyman in the "Boston Medical and Surgical Journal" for March 29, 1866.* There is also a third and median and morphologically symmet- rical leg coming off from the pelvis, and possessing a partly double foot with a median primus (great toe) bearing a nail upon each side, and seven other toes of which four seem to belong to the right, and three to the left, moiety ; but this left foot belongs of course to the right child, and the right belongs to the left child which thus claims four and a half of the eight toes. The leg and foot are less regular and symmetrical than in Wyman's case, and the whole limb is swung out toward the left as if more under the control of the right child, concomi- * The figure is reproduced in Dr. S.J. Fisher's essay upon Diptoteratology, p. 72, and figs. 53 and 54, the description is there quoted in part, and in full in Prof. J. B. S. Jack- son's Catalogue of the Warren Anat. Mus. of Harvard University. B. NATURAL HISTORY. 253 tantly •with the greater bulk of the right brain (see preceding paper). The point to which I wish to call particular attention is the ex- istence of a minute papillary representative of the missing arms, corresponding to the legs which are represented by the fused and median linib ; this is a papilla about *005, in length and slightly constricted at the base ; the surface is slightly wrinkled and a few short hairs spring from the tip ; it is wholly tegumentary, and its cavity contains only loose connective tissue. Fig. 1. Dicephalous Monster, from behind; 1-6 of natural length. Its nipple-like appearance, and its location upon the line of junction of the shoulder regions of the two individuals, suggested its being the result of a fusion of the left nipple of the right child and the right nipple of the left child (the other two occupying their normal positions upon the pectoral regions), but it is im- perforate; and what is conclusive, the real nipples, though small and hardly projecting from the surface, occupy places upon the sides of the junction-line, the right one (left of right child) being 254 NATURAL HISTORY. •030, and the left (right of left child) -025, behind the median papilla, and at a distance of -025 apart ; an elongated mammary gland underlies the left nipple as indicated by the slight elevation in fig. 2, A, but no such is apparent under the other. Fig. 2. A. Integument bearing the papillary limb P, and the two nipples N, N'. B. Median scapula and clavicle from above. C. The same from the side, the scapula divided near the middle line; all of natural size. Immediately beneath the integument upon the line of junction are two bones whose position in reference to the papilla is approx- imately shown by the dotted outline in fig. 1 ; while their forms and connections are shown in fig. 2, B and C. The longer bone is evidently a median and nearly sj^mmetrical clavicle ; it is about -045, in length, is wholly ossified, and presents at its hinder extremity an appearance of epiphysis, which is attached to the anterior slope of the scapular elevation by ligaments, without any synovial capsule ; its anterior extremity gives off a slender tendon which bifurcates at a distance of '005, into the tendons of the two sterno-mastoid ( ?) muscles ; into each side are inserted two muscles, the cleido-mastoid occupying the anterior, and the trapezius the posterior half. The enclosed spaces C M and T B. NATURAL HISTORY. 255 indicate the attached ends of the cleido-mastoid and trapezius mus- cles of the right individual ; the clavicle is strongly curved toward the left individual, as seen from behind, but as seen from the side its outline is nearly straight, fig. 2, C. The scapula is a nearly symmetrical disk of bone with a carti- laginous border which is narrow in front, projects as an angle upon each side, and is broader behind where it is closely connected with a transverse bar of cartilage, excepting an elongated gap upon the middle line ; the scapular disk is convex upon its dorsal surface, rising near the anterior border into a decided elevation or tubercle corresponding with a deep pit P, upon the concave deep surface, as shown in the section C. I am not prepared to express a decided opinion as to the nature of the cartilaginous bar ; but have no doubt that the disk represents the fusion of the inner or vertebral or proximal moieties of the left scapula of the right child, and the right scapula of the left child, at a point proximad of the glenoid cavities so as to leave only por- tions of the acromial spines to unite and form the elevation against which the clavicle abuts ; to the various borders of the scapula are attached muscles, which seem to represent the two rhomboidei, the serratus magnus, the levator angidi scapula?, and the omohyoid ; but as I am still in some doubt respecting the pectoralis major, and the attachments of the teres major and, latissimus dorsi, I will defer an account of them to another occasion ; when, too, the absence of a sternum and the apparent anomalous direction of the clavicle can be accounted for. In general, however, it is evident that the condition of things is like that in Prof. "Wyman's case, excepting that the separation of the two individuals at the shoulders is less complete ; or the union is more so. The result is to reduce so far the median and third arm, that instead of being obviously and unmistakably such it is a mere papilla which but for its position and its relation to the underlying bones would never be regarded as a limb, much less as two arms ; yet it is evident that it is just as much so, morphologically, as is the earliest pad-like rudiment of a limb in the developing foetus ; for it is possible to conceive of a complete series of intermediate conditions with Wyman's case at one extreme and this at the other. It would seem therefore that, in any such system of classifica- 256 B. NATURAL HISTORY. tion of monsters as that proposed by Dr. Fisher, our monster should rank as Dicephalus, tribrachus tripus; op. cit., p. 71. But the question arises whether the name could be retained in case of a still further reduction, so as to leave no external evi- dence of a median limb ; and while this may be of less practical importance in respect to monsters, yet it is akin to the general problem "what constitutes a digit or dactyle" briefly indicated by me.* Note on a Mummied Dicephalus from Peru. — Dr. Chas. S. Swazey of New Bedford has kindly allowed me to bring some photographs of Peruvian relics, and among them is one of a human dicephalus, closely resembling our specimen ; but as it is in a sitting posture and shown from in front, the existence of median limbs is merely to be inferred, the left foot is partly hidden by the right, and the three tibial (inner) toes of the right are turned down. It seems, from this, that monsters occurred among the ancient Peruvians, and that they were not consigned to scientific investigation, but duly mummified.f *lntermembval Homologies, p. 63; Proc. Boat. Soc. Nat. Hist., vol. 14, 1871. fit is stated in Spencer's "Descriptive Sociology" that the "Huacas," or sacred objects of the Peruvians included twins and monsters. b. natural history. 257 The Habits and Parasites of Epeira riparia, with a Note on the Moulting of Nephila plumipes. By B. G. Wilder, of Ithaca, N. Y. The large garden spider with black and yellow abdomen, which is very common in certain parts of the south/and less abundant at the north, was first, so far as I know, described and figured only by Hentz.* Although that author's description is very brief, the spider is readily identified, and it may be better to defer a fuller description until a male is secured ; at present there are some points in its economy worthy of investigation, and I will here indicate them, first quoting in full Hentz's account of the species. "Description. — Black, cephalo-thorax covered with silvery-white hairs ; abdomen barred with bright yellow spots and dots ; thighs usually bright rufous at base, except the first pair. Of a large size, seldom small. Observations. — This remarkable species usually dwells on the margin of waters where it makes a web of strong threads, in which large Libellulce and Melolonthoe, are often caught. The abdomen of the female is flat in the early part of the season, and it is not till August that, being distended with eggs, it assumes the ovi- form shape. Its cocoon is conical, as large as a small plum, like a pear hanging down. Whenever opened it was found full of young spiders instead of eggs. Is it viviparous ? Habitat.— The United States." During the war I had the opportunity of studying certain features in the economy of this species, which at the time, I imagined to be wholly undescribed, and in "Harper's Monthly" for March, 1867, under the title of "200,000 spiders," I gave descriptions and figures of the female E. riparia, of her net and of the cocoon ; also of presumed ichneumonidian and chalcidian parasites found therein. And as nothing has since appeared respecting it, I will here give an abstract of the above mentioned paper, together with some additional observations respecting the escape of the young from the cocoon. * Boston Journal of Natural History, 1847, v, 468, pi. xxx, fig. 5, under the name of E. riparia. A. A. A. S> VOL. XXII. B. (17) 258 B. NATURAL HISTORY. On the 21st of March, 1865, on James Island, just south from Charleston, South Carolina, I found suspended in a bush a pear- shaped cocoon (fig. 1), like that described by Hentz. Between Fig. 1. Cocoon of Epeira riparia; nat. size. the above date and April 2d, I found in the same locality, and chiefly near a ditch, two hundred and five similar cocoons. Fig. 2. A. Vertical transverse section of cocoon of Epeira riparia, containing only the eggs of the spider. B. The same showing the cocoons of the ichneumon, which destroyed the eggs, and which are themselves destroyed by chalcidians. C. Cocoon of ichneumon from which the insect has escaped. 1. Outer, and usually glazed, coat of the cocoon. 2, 3, 4. Second, third and fourth, or inner coats, separated from each other. 5. The pedicel. 6. Looser interior of pedicel. 7. Thickened base of pedicel. 8. Suspensory of the egg-cover. 9. The egg-cover. 10. The eggs partly exposed by separating the cover from the cup. 11. The cup. 12. Loose silk surrounding the cup. 13. Hole made by escaping ichneumon. 14. Ichneumon cocoon. 15. Holes in the ichneumon cocoons made by the chalcidians. 16. Corresponding holes in the spider's cocoon. B. NATURAL HISTORY. 259 The cocoon is usually pear-shaped, ranging from '015, (15 milli- meters) to '022, in transverse diameter, and from *025, to '032, in length. The wall averages *000,5 (^- millimeter) in thickness, and usually consists of four concentric and closely united coats or layers of silk, which are nearly equal in thickness and compact- ness, the outer one (L), however, being usually smoothly glazed without, so as to crackle like thin paper ; sometimes there are but three coats, and in some of these cases, the outer one is not glazed but soft and velvety ; the coats thin out over the pedicel, but not by well-defined edges. At the top of the cocoon is a pedicel or stem (5), hollow and loose in texture (6) above, but broader and denser below, where it is concealed by the body of the cocoon, and having its lower surface or base very firm, like a silken disk (7). The contents of the cocoon are a mass of loose, reddish silk (12) attached above, about the base of the pedicel and apparently also to the inner coat (a special portion of this loose silk, like a cushion (8) attached to the base of the pedicel) ; a kind of saucer (9) of very delicate silk, which is inverted, and suspended by the cushion above mentioned; a cup (11) of the same delicate silk suspended to the lower border of the saucer (which thus forms its cover) by a few fibres of loose silk; a mass of eggs (10), from five hundred to two thousand two hundred in number, enclosed within the cup (at the time these were found, these eggs had evidently hatched, for in their place were found large numbers of little fragments of broken shells) ; many little round bodied spiders, never, in the earlier weeks, less than five hundred in number ; which, when the cocoon was opened, came tumbling out, each swinging by its own little thread, and " looking like so many chickens hung by their tails" (Harper's Magazine, 1866, p. 452, and fig. 12). I have never witnessed the making of a cocoon ; a spider after- ward taken near Boston, Mass., was just finishing her work at 6 a.m. of Sept. 26, by attaching lines from the cocoon to sur- rounding objects. But it may be inferred that the pedicel is first formed, and firmly secured by strong lines in all directions ex- cepting downward ; that to its lower surface the spider affixes the cushion of loose silk ; and to this the inverted saucer ; the eggs are now expressed upward into this, while the spider hangs back downward below it ; the cup is now formed under and about the eggs ; and then around the whole is spun the loose mesh of silk 260 B. HATURAL HISTORY. which serves the double purpose of protection to the eggs and the spiders, and as a primary habitation for the latter before they es- cape and make nets of their own ; finally, the outer wall is formed in three or four consecutive la3rers, and the cocoon is braced by strong lines passing to the surrounding twigs. From the above account it appears that the cocoon must be formed and the eggs laid in the previous summer ; and that in South Carolina, the eggs are hatched as early as the 2lst of March; but although by opening a cocoon every day or two, I satisfied myself that each of them did really contain from five hundred to two thousand living spiders, and although they were kept exposed to the sun and occasionally sprinkled with water, yet during all the time I kept them, namely, until June 15, not one of the entire cocoons was opened by the inmates. On and after the 10th of May, however, they sometimes came out of holes cut in the cocoons, or through openings, hereafter to-be described. Bat first it is important to state that from a single entire cocoon found at Ithaca, N. Y., the spiders escaped through a hole made by them- selves near the base of the pedicel, on the 14th of June, 1873 ; so perhaps, but for an accident which destroyed them, those at the south would soon have made .their way out. The fact, however, remains that the young of Epeira riparia live together for many weeks in a confined space, and with no food excepting one another.* That they do eat each other is cer- tain ; first, because in cocoons opened later in the season, the spiders were found to be fewer in number, but larger in size ; and second, because they were seen to do it, even when out of the cocoon and supplied with other food (as blood) which they seemed to relish. There never was any fighting, however ; the smaller and weaker seemed to understand that for the good of the species (pro bono publico) they must be devoured by the larger and stronger, who performed their part "doucement et sans cholere." It is evident that here is an opportunity for noting the working of "natural selection," upon a large scale; for out of the five hundred young who are hatched, comparatively few can reach maturity, else the country would soon be overrun with them ; the fact being that although the species is widely distributed, yet I * Three cocoons of this species were hrought to me Feb. 26, 1874; and the young spiders are hatched ; without speculating as to the time that may have already elapsed since the' hatching, this gives us nearly four months during which the young remain confined; and it will appear that the cocoon itself must keep out the cold as efficiently as the egg shells, pupa cases and cocoons of insects which appear later in the season. B. NATURAL HISTORY. 261 never found them in such abundance in other parts of the south, and saw only eight cocoons between Charleston and Eutaw Springs, South Carolina, searching the woods bordering the road both going and returning. Of the four hundred and six cocoons obtained on James Island in the spring of 1865, only one hundred and thirty-four were en- tire, and presented no opening whatever. My notes state that one hundred and ninety of the others were pierced, but by what is not mentioned and I do not now venture to conjecture ; but no spiders came out of these before May 10, although the openings were certainly similar to those made by the spiders in the cocoon, mentioned on page 260. Of the remaining eighty-two cocoons, fifty-nine were torn, in one or more places, and through the rents projected loose silk ; having once " seen a little bird about the size of a sparrow, fly at a cocoon hanging in a tree, make one or two quick pulls and then retreat," I am inclined to think all these rents were so caused ; and as these attacks would usually open the cocoon without in- juring the inmates, I drew the inference that this might be a pro- vision of Nature, like the fertilization of flowers by insects, by which the invasion of the cocoon should really permit the contin- uance of the species ; that this is not the only means of egress has been since shown in the case mentioned upon page 260. Parasites. — The remaining twenty-three cocoons presented openings of one, and usually of two sizes ; the larger about -001, and the smaller -000,3 in diameter. Some of these cocoons con- tained a few spiders, but usually only empty shells ; while the origi- nal contents were in all cases crowded to one side and upward by a mass of small oblong cocoons (14) of a whitish silk, and more or less firmly united by threads. In one spider's cocoon, some of the smaller cocoons were empty with a hole in one end corresponding in size and location with the larger holes in the spieler's cocoon (13) ; three were entire and each contained fragments of a single insect, apparently an ichneumon, of which I have at present no fragments which can be specifically identified. The small cocoons in all the other twentj^-two cocoons in this series presented no large holes but instead, many small holes like pin-pricks (15) corresponding to the smaller holes in the spider's cocoons (16) ; and in all these pierced cocoons were fifteen to twenty little black insects, some motionless (pupce), others crawling actively about 262 B. NATURAL HISTORY. (imagines), which are undoubtedly chalcidians, but as yet unde- termined ; all such cocoons contained also the empty pupa skins of the ichneumons, which, having destroyed the spiders before or after hatching, had been themselves devoured by the chalcidians. The chalcidians range from -001, to *002, in length. The ich- neumons range from -005, to -006, in length. Their pupa skins from -006, to -008, and their cocoons from -007, to -010, in length and -008, to '004, in diameter. In the article above quoted, are given figures and descriptions of these parasites and some suggestions as to the manner of their entrance to the cocoon ; but it is evident that a careful investi- gation will be needed in order to elucidate fully the history of this spider and its enemies. Note upon the Moulting op Nephila plumipes. — Mr. Black- wall* has clearly described the moulting of Epeira calopliylla, and Pigs. 3, 4. Moulting of Nephila phimipes. called attention to the fact that the first separation of the integ- ument Qccurs along the border of the cephalo-thorax and not upon the median line. Having witnessed this very often with Nephila * Trans. Linn. Soc, vol. xvi, p. 473, and spiders of Gr. Br., p. 7. B. NATURAL HISTORY. 263 phimijoes, I am able to confirm his description ; and as no illus- trations of the process are known to me, I offer here two repre- sentations of Nephila drawn by me from the same individual, while partly extricated (fig. 3), and while hanging and drying prepara- tory to mounting to her net (fig. 4) ; the position must assist the flow of fluid from the abdomen into the limbs and cephalo-thorax. I have "biographies" of several individuals of this species which were isolated and watched for a greater or less length of time, in a few cases from soon after hatching to the adult condition ; and I have observed remarkable differences of disposition and habit, quite comparable to those commonly ascribed only to human beings and the higher animals ; there seem to be truly psycholog- ical individualities even among spiders. Pig. 5. Nephila plumipes, a few days old ; natural size and enlarged .* Fig. 6. Cocoon of Nephila plumipes, or loose silk attached to the lower surface of a leaf. *This, with figs. 3, 4 and 6, and fig. 1 of the following paper, are electrotypes of cuts in rny article " Memoirs of a Cripple," in "Our Young Folks " for Sept., 1866, furnished me at cost by Messrs. J. R. Osgood & Co. 264 B. NATURAL HISTORY. The Nets of Epeira, Nephila and Hyptiotes {Mithras). By B. G-. Wilder, of Ithaca, N. Y. Most Epeiridaz ("garden" spiders or "geometrical" spiders) construct a net in the form of a nearly circular disk which is sus- pended at various angles, but probably never quite vertical or horizontal, although the former position is generally predicated of the ordinary species, and the latter of Tetragnatha and some species of Epeira. The net consists of a spiral viscid,, line laid upon a framework of dry radii which converge to a point which apparently coincides with the centre of the disk, but may vary a little therefrom, and, according to Emerton,* is usually nearer the top than the bottom. In some cases, and perhaps in all, the radii are first connected by a primary spiral dry line at greater intervals than the secondary viscid line ; this is begun at the centre and completed at the periphery, and according to Emerton {op. cit., 479) is removed as the viscid line is laid on (it is per- manent in Nephila) ; the viscid line is begun at the periphery and completed near the centre ; the spicier takes position at the centre upon the lower surface of the net, and always with its head down- ward. The net of E. vulgaris is figured by Emerton (Am. Nat., vol. ii, PL 2), that of E. riparia by me (Harpers' Magazine, March, 1867, p. 463), and those of several British species by Blackwall, in his great work, "Spiders of Great Britain and Ireland." The net of Nephila plumipes-\ consists wholly and in- variably of a series of looped viscid lines, laid upon radii which gradually increase in length from the upper to the lower region of the net so that the "centre of radiation" is very much nearer the upper than the lower margin, and is, in fact, more nearly in the upper of the two foci of the elliptical net ; the radii are very numerous and closely set ; secondary radii are placed in the wider intervals commencing at various distances from the centre ; and the primary dry line is looped like the viscid line, and is re- tained; the necessity for this extra support being evident from the great size of the nets, which range from one to four feet in diameter, and are strong enough to hold a light straw hat. The free radii are in the same plane with the others, are always ♦American Naturalist, 1868, p. 478. t As described and figured by me in " How our new Acquaintances Spin," Atlantic Monthly, August, 18GG, from which fig. 1 is taken. B. NATURAL HISTORY. 265 in the upper region of the net, and occupy about } of its area ; they are more irregular than the others, and crossed by irregular lines so as to merge gradually into the outer scaffolding, and are crossed by neither the dry nor the viscid looped lines. Fig. 1. Net of Nepliila plumipes, made in a wire frame, and photographed upon wood ; reduced. In nature, the free radii, as above described, occupy about | of the area ; but the web of which a figure is given was made upon a wire frame ; the limits of which seem to have interfered with the extension of the loops above the level of the centre of radiation. Hyptiotes (of Ithaca, N. Y.). — The spicier, wbose web. will now be described, no doubt belongs to the genus Hyptiotes TValck. (afterward and more generally called Mithras) ; of which there have been described at least two species, H. paradoxus and H. jlavidus, from Europe, the former having been lately found in Great Britain.* I refrain from giving a specific name, because if there prove to be only one species in the limited states, we may have to retain the name cavata which Hentz applied to the species found by him in Alabama, and to which he gave a new generic name Cyllopodia ;f Hentz, however, states decidedly that it has but six eyes (whereas *It is my intention to publish shortly a full description of the spider, with refer- ences to the synonymy kindly furnished me by Messrs. Blackwall and Cambridge of England, and Win. Holden of Marietta, Ohio. tBost. Journ. of Nat. Ant. 1847, vol. v, p. 46G. 266 B. NATURAL HISTORY. my specimens have eight), and his descriptions, both generic and specific, are hardly full enough for identification : he knew nothing of the net. Mr. Emerton has a few specimens of both sexes, taken in Massachusetts, which I have not yet examined critically, but I have not heard of its discovery in other parts of the country. I have not been able to find specimens of Hyptiotes earlier than the middle of September, and they seem to disappear about the middle of November ; I have never seen young specimens, but certain little cocoons are very numerous in the same localities, so I suspect them to be made by them. These cocoons sometimes contain about a dozen egg-shells ; in which case the spielers have evidently escaped by pushing up the base of one of the guy lines, which seems fitted like a trap door ; sometimes the cocoon is empty, and then the outlet is' a' ragged hole at one side ; and in one I found remains of some winged insect, dipterous or hynienopterous, evidently a parasite as with the Epeira riparia (see preceding paper), which may account for the ragged holes in the other specimens. In some cocoons there are eggs as yet unhatched, and I may succeed in rearing the young. The cocoons are about -002, in diameter ; and those which contain entire eggs include also some loose silk. It will be seen that the habits of Hyptiotes, and the form of its net, with its mode of construction, are sufficiently peculiar to ob- viate any danger of confounding it with other genera ; I have not yet seen the work of Ausserer in which Mr. Holden thinks the net of the European species is referred to, and do not think any extract from it has appeared in this country, so that a full des- cription of the net may not be out of place. Specimens of Hyptiotes were first found by me in the woods bordering Cascadilla Creek in Ithaca, N. Y., in the latter part of September, 1870 ;* their dull color, their small size (about -003,5 in length) and their habits of remaining fixed against the hemlock twig, to which the net is attached, may account for their having escaped observation during the two previous years when I col- lected in that locality. This species seems usually to construct its net just before day- break, and I have only twice observed the process ; on the 4th of * Of about fifty specimens then taken, all proved to be females, nor did I find any males until the 28th of Sept. 1873; these are smaller and fewer in number and make no net, being generally found near that of some female. In this as in previous papers I have added notes since the time of presentation. B. NATURAL HISTORY. 267 October, 1870, I saw the last cross-line (that nearest the apex) finished, and four years later, Sept. 28, 1873, I witnessed the formations of the fine lesser lines : as the process was identical in the two cases, there seems good reason to regard it as normal. Some account of this and of the habits of the spider was given at a meeting of the Cornell Univ. Nat. Hist. Soc, for Oct. 10, 1870, when also specimens of the female were shown. The male was exhibited on the 10th of Oct., 1873, at a meeting of the same society. Fig. 2. Net of Hyptiotes " upon the stretch." BB, base line. A, apex. O, origin of apex line. R' " '" "" the four radii. A..L., apex line. V " '" etc., viscid lines. S' " '" "" Points of attachment of the viscid lines upon the radii; forming little steps upon the latter. SI. Slack-line between the first and fourth legs. This is better shown iii the enlarged lower figure, where only the legs of the right side are represented. In the upper figure the spider is shown rather large and the net rather small ; the base-line should also be more extended before attaching to the branch at either end. The net is triangular in form, and consists of four radii, never more or fewer, crossed by several (6 to 10) independent viscid lines ; the centre of radiation is prolonged into a single nearly 268 NATURAL HISTORY. horizontal strong and short line which is attached to a branch or twig ; the outer ends of the radii are attached to a second strong line more or less nearly vertical and nearly at right angles with the first. The radii and base line probably involve no unusual process ; but the entire independence of the viscid lines contrasts strongly with the spiral or looped lines of Epeira and Nephila. At the time of the second observation above mentioned, the spider had completed the base line, B. B., the four radii (B/ " //; //;/), and the four viscid lines nearest the base V ;/ '" iv), she was just then passing along the upper radius (R/) from the direction of the apex (A) ; having reached the viscid line (iv) last com- pleted it turned about, seemed to make some rough measure- ments of distance with its body, and then, by drawing, its spin- ners along the radius for a short distance (about .002,) formed thereon the same kind of attachment of a new line which I have described and figured in the net of Nephila, and- which, though not alluded to by authors, is perhaps generally adopted as much more secure than contact at a single point. The spider then allowed her abdomen to fall away from the radius, hang- ing therefrom by the first and second pair of legs, and braced away from it by the third pair, she began to move the fourth pair simultaneously to and from the mammulse, so as to ex- tract therefrom a very viscid and elastic line which had a faint yellowish tinge ; doing this, she at the same time moved slowly toward the apex, to a point where the interradial spaces were narrow enough to permit her to cross to the second ; this she did, ceasing at the same time to draw out the line, which, as she now returned toward the fourth viscid line, contracted considerably, so that it was nearly of the proper length when she attached it to the second radius at a point about as far from the fourth vis- cid line, as it had been begun upon the first radius ; again turning and making the extended attachment as before she repeated the drawing process so as to carry the viscid line to the third radius, and from this to the fourth. She then ceased drawing the line, and returned to the first radius by way of the crossing (C), began a sixth viscid line, and afterward a seventh, eighth and ninth, all in the same way and at about the same distances apart. The rapidity of movement of the fourth pair of feet is very B. NATURAL HISTORY. 2G9 great ; by considerable effort I could move one hand at about the same rate, and found it to average, at least, five times in a second, or three hundred in a minute ; about ten minutes were required to complete these five viscid lines, the time spent in returning being very short ; and as the other four and longer lines must have taken at least fifteen minutes, our spider may be estimated to move her hind legs definitely and nearly without cessation about 7500 times in less than half an hour ; an estimate which is cer- tainly far within the facts. I have not yet satisfied myself respecting the exact nature of this viscid line,* beyond the exceeding viscidity and elasticity al- ready alluded to ; but I do not think that it is "curled" like that of the Cinijlonidce, as described by Blackwall (op. a*£.,p. 139), and figured by Miss Stavely (op. cit., p. 114). [For the rest of the description the present tense is applicable, since it applies to the often witnessed proceedings of many differ- ent individuals.] As soon as the net is completed, the spider takes her position on the apex line (AL) at about an inch from the point of attach- ment (O) with her head toward the net ; seizing the line between the first and second pair of feet, she walks slowly backward, "foot over foot" with the. fourth pair, until she reaches the point of at- tachment (0) ; into which, or into the line near it, she fixes the fourth pair of feet ; this proceeding puts the whole net upon the stretch, draws the second and third radii toward the apex, and thus alters the direction of the base line ; the slack line (SI.), which has now accumulated between the points upon the line grasped by the first and second, and the fourth pair of feet, is held away from the body by the third pair, as seen in the lower figure (only the legs of the right side are shown). I have not yet measured the strain put upon the net, but it is evidently considerable, yet these spiders remain immovable for hours, like. a set spring; so motionless are they, and so com- pactly placed are the legs, that they look more like projections of the wood than living creatures, and no insect would ever mis- trust danger from them. But when the web is struck by an insect, the spider shows that though quiet she is watchful ; loosing her fourth feet, the strain is relaxed and the whole net regains its original condition with a sharp snap, which causes the elastic *An account of this and of the parts concerned in its production will be given hereafter. 270 B. NATURAL HISTORY. lines to vibrate in all directions and generally entangles two or more of them upon the insect ; should this first attempt fail, the spider, which has been carried sharply forward with the line, but which has retained her equilibrium by means of' the third pair, again walks backward and again lets go ; this is sometimes repeated six times in quick succession ; when satisfied that her prey is entangled, she advances a few steps at a time, apparently feeling her way (as do the Epeiridse generally), and approaches the quarry by the nearest radius ; the subsequent operations are essentially those of the Epeiridse, and need not be here described ; but in some cases, while advancing toward the prey, she cuts the line with her jaws between her front and hind legs, which allows the net to collapse somewhat ; the spicier, however, has attached a new line in her rear, so that the continuity is not wholly broken ; by repeating this, and cutting all the radii, she is enabled at last to gather the entire net within her front legs and to throw it, like a blanket, upon the struggling prey, which is thereby hopelessly entangled ; in such cases, therefore, and, in fact, generally, an entire net is destroyed in making a single capture. Farther account of its habits would be here out of place, but there are some points to be noted in respect to the plan of the net and the mode of its formation. 1. Unlike both Epeira and Nepliila the number of radii is con- stant; in the hundred or more nets which I have examined, there have been always four radii. 2. But the distances between them, the number of viscid lines and their intervals, like the several dimensions of the net, vary considerably, as shown by the following table. TABLE OF DIMENSIONS OF THE NET OF HYPTIOTES IN MILLIMETERS; TAKEN FROM TEN NETS. Maximum Mean Minimum. r~ so box a X .150, .035, .010, °So» «■*= s ® " a " 5 hT P .210, .150, .100, o +3 8*. S-s <» P,^ £> I5-1 33O £«•? Bot> hi .180, .150, .110, .110, .140, .075, fe-c B. NATURAL HISTORY. 271 In fact, the net of the spider, like the cell of the bee, as demon- strated by Wyman, is never the model of geometrical precision which we have been led to believe by superficial examination. I have never yet seen the net of any spider in which the eye alone, unaided by instruments, could not discover irregularities, which, if they existed upon a like scale in human workmanship, would be regarded as serious imperfections. But when it is remembered that insects measure spaces in much the same way that we do, by the eye or the limbs, the only wonder is that metaphysicians and theologians ever ascribed to their work an exactness which men attain only through exceeding care and delicate mensuration. 8. Like the nets of Epeira and Nephila, and probably all others, the net of Hyptiotes is not vertical but inclined at an angle which varies greatly but is generally more than 45°. 4. So too, the inclination of the longitudinal axis of the net varies greatly. I have never seen the apex-line inclined upward from its origin, but have occasionally seen it slope downward at about 45° ; usually the angle is between this and the horizontal. 5. The independence of the viscid lines is very striking, but it is evident that the " drawing out " method of this spider would not permit the formation of viscid lines from below upward, with- out risk of entanglement. 6. The "drawing-out" may impart to the viscid line an elas- ticity which enables it to shrink to the proper length, after having been long enough to enable the spider to pass from one radius to the next near the apex ; it being forced to do this on account of its small size as compared with the interradial spaces ; the alter- natives would be either — 1. To make a larger number of radii which, however, would increase the resistance to the strain, and lessen the vibrations of the viscid lines : 2. To spin a series of primary cross-lines, not viscid, equal in number to the secondary viscid lines, and to use the former as means of crossing while spinning the latter in the ordinary way, then cutting them away as described by some Epeiridce; at present we may hardly conjec- ture the causes which led to the exclusion of these hypothetical methods, but meanwhile it is to be noted : — 7. That the series of viscid lines must be commenced at the larger and concluded at the smaller extreme, because otherwise either — 1. Each succeeding line would have to be engineered by its predecessor which would be between it and the crossing : or 272 B. NATURAL HISTORY. 2. If the spider chose to effect her crossing at the base line, then the shorter lines would have to be carried and stretched the greater distance, and vice versa; whereas now, that distance de- creases with the length of the viscid lines themselves. 8. The net is triangular, the section of a circle, unlike that of any other genus ; and, in idea at least, may be regarded as filling the vacant space in the net of Nephila as compared to that of Epeira; so that we may saj7 in mathematical language, Nephila-\- Hypiiotes = Epeira ; in more home]}7 phrase the net Epeira is a whole pie, that of Nephila is a pie lacking one-sixth, while that of Hyptiotes supplies the missing piece. Fig. 2. Diagram representing tlie-forms of nets of Nephila, N~., Hyptiotes H., and Epeira E. Zoological relations. — The 'above comparison of the net- patterns of Epeira, Nephila and Hyptiotes is suggestive, but by no means conclusive ; and we need to know much more concerning all of them, especially their embryology, before venturing an opin- ion respecting their zoological relations : particularly since our highest authority is now inclined to place Hyptiotes among the Cinflionidce (Blackwall Ann. and Mag. of Nat. Hist. 1864, p. 436). It is worth noting, however, that the gap between the continuous spiral net of Epeira and the returning loops of Nephila may be regarded as lessened b}*- the following considerations. 1. Mr. Blackwall states that E. calophylla " usually employs a radius as a means of communication between its net and .a small tubular cell of white silk which constitutes its retreat ;" . . . and on reaching this radius it retraces its steps until it reaches a point on the opposite side of the radius, and by repetition of this the net is made to consist of a series of looped-lines, " arcs of circles :" it does not appear that this "free radius" is always in the same region of the net, although it is probably one of the upper series, as seen in the figure by Miss Stavely (British spiders, p. 246). 2. In several nets of a small species which is common in Ithaca, N. Y., I have (Sept. 28, 1873) seen the addition of four looped lines (like those of Nejjhila) to the lower border of the net; and in May, 1871, I found a deserted net built in an angle which B. NATURAX HISTORY. 273 consisted of fourteen turns of the spiral line which formed the limit of the net upon the side toward a fence post, but on the other three sides (the top, the bottom, and the right side), the net was extended by ten looped lines : this augmentation of the lower region of the net would leave the centre of radiation above the geometrical centre, as Emerton states to be the case (Am. Nat., II, 478) with E. vulgaris, but without explaining whether it is due to the addition of independent lines or of loops or the increase of the spaces between the spiral lines. Now since all these spiders hang from the lower surface of the inclined net, and always head downward, it is evident that, for the larger ones especially, it must be very much easier to reach even a distant point below their level, or even at one side, than to turn and ascend ; and if it shall prove, upon closer scrutiny than has yet been given, that the true Epeiridm may, upon occasion, and under any circumstances, construct a part of their nets of looped lines, it might be conjectured that a habit thus formed would become confirmed, intensified and transmissible ; Nephila might in this way be regarded as a derivative from Epeira.* The simple triangular net of Hyptiotes, with its uniform number of radii and small number of cross lines, might be regarded per- haps as a further specialization from that of Nephila, the circle of the Epeira being now reduced from five-sixths to one-sixth of its area, and the dry space above the centre in the net of Nephila, represented by a single radius, the apex line ; but in some respects it is easier to compare the net of Hyptiotes with that of Epeira calophylla; the apex line would then represent the single free radius. The ordinary Epeiridm, as well as Nephila, are accustomed to vibrate their nets, when touched by insects, anil this habit may be the basis of the remarkable method by which Hyptiotes en- tangles its prey. Repair of nets. — It is known that the Epeiridm renew the entire net occasionally, and they have been seen to chew it, for the pur- pose, apparently, of extracting the gum. In most cases, the Nephila renews only one-half of its net, which varies from one to * A comparison of their forms looks the same way; for the young Nephila is rourid bodied like the Theridion, and makes at first a similarly irregular net of lines crossing in all direction^ ; later it passes through the more elongated form of the ordinary Epeira and finally attains the almost cylindrical outline proper to its genus. See previous paper. A. A. A. S. VOL. XXII. B. (18) 274 B. NATURAL HISTORY. three feet in diameter ; it cuts the net in two vertically, and stuffs the mingled silk, gum and dust between its jaws, chewing it for sev- eral hours, and finally rejecting a black and very hard pellet which seems to consist almost entirely of dust ; the half of the net thus destroyed is then renewed by looped lines necessarily ; the next day, the other half may be renewed in like manner. It would appear that most Epeiridce renew the entire net at once ; but it will be worth while to notice whether the larger species do not, like Nephila, renew only one-half at a time, for if so, they must employ looped lines instead of a continuous spiral. As stated above, the entire net of Hyptiotes is usually destroyed in the capture of a single insect ; and as the rejected pellet is quite dry, we may infer that the spider appropriates the viscid portion of the net enveloping the prey. I shall probably propose the name Americanus for this spicies of Hyptiotes ; for although this may be the species referred to by Hents as Cyllopodia cavata, yet his description and figure are in- sufficient for identification. The Need of a Uniform Position for Anatomical Figures. By Burt G-. Wilder, of Ithaca, N. Y. The convenience of a uniform position for anatomical figures is sufficiently evident to all ; and the neglect of such uniformity is a source of delay and even misinformation to beginners. The posi- tion with head to the left is advocated partly because it is more natural, in dissection and drawing ; partly because the only author, Professor Agassiz, whose figures are uniformly placed, many years ago chose that position, as may be seen in the "Poissons fossiles." The figures in Huxley's and in Owen's Comparative Anatomy of Vertebrates are often scarcely intelligible, on account of reversed positions, and the larger number of authors seem to regard the matter as of no importance whatever. b. natural history. 275 Lateral Position of the Vent in Amphioxus and in the Larvae of Eana Pipiens. By Burt GL Wilder, of Ithaca, N. Y. The posterior opening of the alimentary canal in Amphioxus lanceolatus has been so variously described and figured that a brief historical sketch is here given.* Historical sketch. — It does not appear that Pallas or Costa or Yarrell remarked any peculiarity in the cloacal region, and I have not seen the earlier papers by Retzius and Midler. Couch (4 (1838) 382) merely states that "the vent is at the length of one- third of the body from the tail," but as in all my specimens the * The following list probably includes all the important original papers upon this genus; in the text they will be referred to by their numbers as here arranged ; the last number will indicate the page and the middle one, when it occurs, the volume; the list of general works in which Amphioxus is mentioned occurs upon page 278. Bibliography (special papers). 1. Pallas, Spicilegia zoologica, fasc, xv, p. 19, fig. 11., t. 2. Costa, Annuario zoologico, 1834. 3. Yarrell, History of British Fishes, 1836, p. 468 (2nd ed. ii, p. 618, 3rd ed. i, p. 1.) 4. Couch, Mag. of Nat. Hist. 1838, p. 381. 5. Couch, Fishes of Brit. Islands, p. 415, pi. 248. (date ?). 6. Costa, Fauna del regno di Napoli, 1839. 7. Retzius, Monatsbericht der Academie der Wissenchaften, 1839, p. 197. 8. Rathke, Bemerkungen iiber den Ban des a. L, 1841. 9. Sundevall and Loven, Forhandl. Skand. Naturf. 2nd mode, Kjobenh. 1841, p. 280. 10. Goodsir, Trans. Roy. Soc. Edinburg, xv, p. 1 and Ann. of Nat. Hist, vii, 346, 1841 : also Anatomical Memoirs, vol. 1. 11. MUller, Ueber den Bau und die Lebenserscheinungen des a. I. Abhandl. Ak. Wiss. Berlin, 1842, pp. 79-116, Taf. 1-5. 12. Kolliker, Ueber das Geruchsorgan von A. Archiv fur Anat. 1843, pp. 32-35, Taf. 11, Fig. 5. 13. Quatrefages, Comptes rendus xxi, p. 519, 1845. 14. Quatrefages, Sur P Amphioxus, Ann. des Sciences Nat. 1845, pp. 197-248, PI. x-xiii. 15. Gray, A. belcheri, Proc. Zool. Soc. 1847, p. 35. 16. Miiller, Monats. Akad. Wissen. Berlin 1851, p. 474. 17. Sundevall ( Branchiostoma elongatum) Oefuers, Vet. Ak. Forhandl. 1852, p. 147. 18. Sundevall (B. caribceum) Op. cit., 1853, p. 11. 19. Max Schultze, Verhandl. Naturhist. Vereins preuss. Rheinl., xix. Sitzungsber. p. 197. Also in Siebold's andKolliker's Zeitschrift iv, 1852, p. 416, taf. 13, figs. 5 and 6. 20. Kroyer, Danm. Fisk, iii, p. 1,087 (date ?}. 21. Steenstrup, Oefuers. Dansk. vid. Selsk. Forhandl. (1863) 1864, p. 238. 22. Marcusen, J., Comptes rendus, 1864, pp. 479-483. Also in Ann. and Mag. of N. H., 1864, xiv, pp. 151 and 319. Also in Rev. et Mag. Zool. 1864, xvi, p. 79. 23. Kowalewsky, Mem. Ac. Sc. St. Petersb., 1867, xi, No. iv, pp. 16, 3 pi. abstract of same in Bibl. Univ. Art. 25, 1866, Bull. Sci. pp. 193-195, transl. in Ann. and Mag. of Nat. Hist. 1867, p. 69. 24. Bert, Comptes Rendu 1867, p. 364 or Ann. and Mag. of N. H., xx, p. 302. 25. Owsjannikow, Bull, de la Ac. Impe. des Sci. de St. Petersb., tome xiii, No. 4. pp. 287-302, 1868. 26. Moreau,Obs. sur la struct, de lacorde dors. Comptes rendus, May, 1870, p. 1006. 27. Moreau, Note sur la region cranienne, Comptes rendus, May, 1870, p. 1189. 276 B. NATURAL HISTORY. post ventic region forms only f or £ of the whole length, Couch probably referred to the "abdominal pore." It is worth}' of note, however, that Couch's figure, though rude and in some respects inaccurate, rightly indicates the fact, apparently overlooked by all other observers before and since, that the ventral border of the left muscular mass retreats a little at the cloacal region (as shown in my figures) so as to expose the mesial surface of the right muscular mass or the cloaca itself when distended. Goodsir (10 (1841) 382) says "The anus is in the form of a longitudinal slit," as appears also in all his figures, one of which is reproduced herewith (Fig. 1. G). These figures have the loca- tion of the vent nearly correct in proportion to the length of the body, but the author states that the " anal fin is interrupted at the anus," 375, whereas it is usually, if not always, widest at that point. It must be remembered, however, that Goodsir's observa- tions were confined to two individuals, and his dissections to but one of these, and while correcting his errors, we are more inclined to wonder at the amount of new information which he obtained from so scanty material. Fig. 1. G. Hinder part of Amphioxus, from below ; copied from Goodsir, PI. 1. Fig. 4. M. The same, from the left side; copied from MUller, 11. Taf. 1. Fig. 1. Q. The same, from the left side; copied from Quatrefages, PI. xiii, Fig. 1. From his second paper (11, 1842) it appears that Muller had plenty of material ; he rightly locates the vent opposite the broad part of the caudal fin (as seen in Fig. 1, M) making the intestine project slightly as a narrow tube with oval orifice ; his description is as follows (translated): "The vent lies on the left side of the abdominal fin ; this anomalous position of the vent upon one side of the anal fin recalls a similar peculiarity with Lepi do siren;"* both figure and description show therefore that Muller supposed the vent of Amphioxus to differ from that of most vertebrates, merely in its lateral position, and no allusion is made to the pecul- iarity in the concluding general remarks. * It will be seen hereafter that in this genus the condition of things is quite unlike that in Amphioxus. B. NATURAL HISTORY. 277 In the somewhat extended paper of Quatrefages (14) it is not easy to separate his own observations from his summary of pre- ceding ones ; as seen in Fig. 1, Q, the vent is the oval orifice of a simple tube which opens far in advance of the expanded caudal fin, which also is shown rather shorter than is natural ; as in Muller's figure, however, the vent is correctly shown to the left of the "abdominal segmented canal." Quatrefages' description (translated) is as follows : "The anus lies at a point where the membranous border enlarges into a lancet form, it opens upon the left side of the abdominal surface of the body, close to (tout aupres) a membrane which occupies the median line." p. 201. Later observers seem to have overlooked the " anomalous loca- tion of the vent," referred to by Miiller and Quatrefages. The formation of the anus, by a gradual constriction of the borders of the "secondary cavity" is described by Kowalewsky (23, pages 3, 4, 5, 7) ; the figures of the earlier stages indicate that the anus is median ; some of the later ones show it as if on the left and others as if on the right side ; but the text nowhere refers to any unsymmetrical position, which is the more noteworthy be- cause attention is called (10) to the unsymmetrical character of the oral aperture. We may conclude that our author, while no doubt well aware of the general opinion respecting the vent of the adult, did not under- Fig. 2. (copied from Kowalewsky. Entwick. des Amphioxus; the caudal region of the embryos shown in Tig. 22, 23 and 28, corresponding to A, B and C, respectively. A. An embryo of sixteen hours, seen from above, showing the outline of the intes- tine which narrows and opens at the anus a apparently upon the dorsal region of the body, with a single series of ciliated epithelial cells behind it. The letters R and L are added better to designate the relative position of parts. B. An embryo of twenty-four hours, seen from the right ; a, the anus which appears to open on the right side of the body. C. An older embryo seen from the left, on which side the anus appears to open ; and this is the more confusing from the considerable backward extension of the caudal region. No reference is made in the text to the exact position of the orifice. 278 B. NATURAL HISTORY. take to elucidate the manner in which this condition was reached ; although, had he so chosen, his opportunities and the skill else- where displayed, would have enabled him to clear up the obscurity which now rests upon it. Most systematic works and zoological text-books* published since the discovery of Amphioxus include more or less complete accounts of its structure ; but as their authors have not published separate papers upon the subject, one can only conjecture the extent of originality in their descriptions. The recent and very complete work of Claus (51) states that the "vent is somewhat laterally placed;" and further (p. 830) that the development (according to Kowalewsky) involves " strik- ing asymmetry with respect to the mouth, vent," etc. Schmarda (52, 302, fig. 501) gives a somewhat altered copy of the figure from Quatrefages, but no reference to the vent. Huxley (55, p. 117) says that the "anal aperture is a little to the left of the median line," yet his figure, apparently copied from Miiller, is reversed so as to bring the vent upon the right of the anal fin. Troschel (59, 284) says that "the fin passes to the right of the vent." Owen (56, 1, 31, fig. 23) gives a purely diagrammatic figure of the organs of Amphioxus, in which the intestine opens on the median line, and the text contains no allusion to a peculiarity in that region. Clark (60, fig. 226) copies Owen's diagram without comment ; and Gegenbauer (53, 788), in like manner, copies Quatrefages, merely saying (p. 799), "Die Cloaken bildung fehlt bei Am- phioxus." Hseckel offers a figure (61, Taf. xiii), which mainly resembles * systematic wokks (arranged in no special order). 51. Claus, Grundzuge der Zoologie, 1872, 828. 52. Schmarda, Zoologie, 302, fig. 501. 53. Gegenbauer, Vergl. Anat., 1870, 778, fig. 256. 54. Rolleston, Forms of Animal Life, 1870, lxxxiv. 55. Huxley, Anat. of vert, animals, 1871, 116, figs. 28 and 29. 56. Ovveu, Comp. Anat. and Phys. of Vert. 1, 31, fig. 23. 57. Agassiz and Gould, Principles of Zoology, 1818, 181, fig. 153. (Shows correctly the position of vent.) 58. Vander Hoeven, Hand book of Zoology, 56, 185S. 59. Troschel, Handbuch der Zoologie, 1871. 60. Clark, H. J., Mind in Nature, 1865, 61. ILeokel, Natiirliche Schopfungsgeschite, 1872. 62. Gunther, Catalogue of Fishes in the British Museum, vol. viii. B. NATURAL HISTORY. 279 that of Quatrefages ; and Gkinther (62, 513) enumerates, among the generic characters, " a low rayless fin runs past the vent ;" so far as I know the point is not alluded to by other sj'stematic writers. It appears therefore that to many the lateral position of a nor- mally median primary opening seems to require no mention, and that when the asymmetry is alluded to, it is not certain whether the vent is lateral and the fin median, or the reverse. The reception of a large number (about one hundred and fifty) of specimens, well preserved in spirit,* and the subsequent oppor- tunity of examining sixty specimens from the coast of Florida, belonging to the Museum of Comparative Zoology ,f have enabled me to investigate this point quite fully. Nothing of the exact structure of the venti can be made out with the naked eye ; in addition to the dissection of many indi- viduals under the lens, I have made about two hundred micro- scopic sections of the cloacal region ; and the following account is based upon their careful and prolonged comparison. It would be more amusing than instructive to enumerate the many and different opinions successively formed in the course of this investigation before the present conclusion was reached, and while admitting the possibility that the true condition of things is not yet known, I shall ask of the critic to state the amount of material upon which his contrary opinion is based. I am well aware of the insufficiency of both figures and description, espec- ially in respect to the minute anatomy of the tissues ; upon some of these points I have nearly made up my mind ; but as all of them are more or less involved in the general structure, and some of them are quite differently represented by different authors, it seems * Collected at Naples and sent by mail by my friend and former student, W. S. Bar- nard, S. B., Ph. D. t Just as this paper is going to press, Prof. Putnam has kindly loaned me two speci- mens from the Florida coast which agree so entirely with the specimens belonging to the Mus. of Comp. Zoology, and are so immediately distinguishable from the Naples specimens, in form and in the proportions of the regions, that I feel almost assured of the specific distinctness of the Amphioxus from the two localities; but, as will be ex- plained farther on, no conclusion upon this point can be regarded as reliable unless based upon the accurate measurement of many specimens, and the enumeration of the segments composing their different regions : this will take time, but will be done as soon as possible. J The terms cloaca and vent are here used provisionally ; at present, notwithstanding all that is known of the different morphological and physiological relations of the ali- mentary, urinary and generative outlets in vertebrates, as briefly stated by Huxley, 109, 131, 138, the above terms are not clearly discriminated from rectum and anus. 280 B. NATURAL HISTORY. better to defer a discussion of them until the completion of the study which I am now making of the entire organization of this lowest, and in most respects, anomalous vertebrate. This paper may be regarded as a preliminary notice of a single part of the subject. 1 Fig. 3. A. AmpMoxus ; seen from the left, natural size; V, the vent; A P. The abdominal pore. B, C, D. Transverse sections at middle of body to show different condi- tions of ventral wall in different individuals. B. A cross-section of the body at the middle of its length, showing the " abdominal groove." C. The same of a Florida specimen, in which the abdomen is flat, or but slightly convex. D. The same of a Naples specimen, full of eggs, in which the abdominal groove is obliterated. The simplest presentation of the subject will be an explanation of the figures. Fig. 3 shows an AmpMoxus (from Naples) of the natural size, head to the left ; no details of structure are given, but there is no question respecting the existence of an expanded vertical fin around both ends of the body; the notch V indicates the location of the vent, and the notch AP the location of the abdominal pore. Most of the Naples' specimens present the abdominal groove described and figured by Muller as formed hy two lateral folds of the integument extending from the mouth to the abdominal pore (Fig. 3, B) ;* a specimen sent from Naples by Prof. Panciri to the Museum of Comparative Zoology is distended by the enlarged re- productive organs, and these folds are wholly obliterated, together with of course, the groove (Fig. 3, D) ; and most of the Florida specimens (taken in May), in which the reproductive organs are less bulky, have loose ventral parietes, as if regaining the grooved condition during the gradual discharge of the reproductive pro- ducts (Fig. 3, C) ; so it is quite possible that the folds and grooves are periodical appearances for the accommodation of the repro- ductive development. Position of the Vent. — The position of the vent with respect to the fin and length of entire body is very differently represented *A similar groove exists in the male pipe-fish ( Syngnathus) but is located behind the vent. B. NATURAL HISTORY. 281 by Muller and Quatrefages ; in all my Naples specimens the vent is as in Miiller's figure opposite that part of the fin which first gains its greatest depth, passing from before backward or just before it begins to decrease in depth, passing from behind for- ward.* In one of the larger specimens from Naples .045, in length (about two inches) the vent is .005, from the tip of the tail, and the abdominal pore .009, in front of it, or .014, from the tip ; the latter opening is therefore about one-third of the length from the tip and the former one-ninth. Or, assuming the length of the body to be 100, the post poral region is .31 and the post cloacal region .11. Miiller's figure yields the following ratio, post poral region .13, post cloacal region 4, while according to Quatrefages' figure the post poral region is .41 and the post cloacal .23. But as one of the Florida specimens, .043 in length, gives the same regions as .25 and .9 respectively, we may infer the existence of considerable variation. It is my intention to present a large series of accurate measurements of specimens from various localities as one element in the determination of specific or variety differences. TABLE OF PROPORTIONS OF AMPHIOXUS, AS DERIVED FROM SPECIMENS FROM NAPLES AND FLORID\, AND FROM THE FIGURES OF Mt)LLER AND QUATREFAGES (IN MILLIMETERS). o C A 60 O bo o so S OS « a ■a -3 *" a © P"