/ r t/t . THE MYOLOGY OF THE BAVEN. ru O; 1 2! D D O m D O / / THE __ MYOLOGY OF THE BAVEN (Corvus cor ax sinuatus). A GUIDE TO THE STUDY OF THE MUSCULAR SYSTEM IN BIRDS. BY E. W. SHUFELDT. HOtttfOtt: MACMILLAN AND CO. AND NEW YORK. 1890. The Right of Translition «ml Keprodiictioii is Reserved. RICHARD CLAY AND SONS, LIMITED, LONDON AND BUNGAY. PEEFACE. THERE has not yet been published, so far as the writer is aware, any work devoted to a complete account of the muscles of any single species of the Class Aves, — a work fully and practically illustrated, and one that would prove itself to be of service to those either engaged in the general study of the morphology of vertebrates, or to those special students who may be investigating the myology of birds. At the present time, — when the study of the structure of animals is becoming far more general, as one of the most efficient aids to observation and mental training, than it was so considered a number of years ago, — books of the class which your author has here endeavoured to produce come to be very useful. Birds stand among the most easily procurable subjects for the use of the demonstrator at the laboratory, or for the student to employ in his own researches at home as illustrative of certain parts of his course in biology. And it was to fill this so important a gap, as the lack of a suitable volume devoted to the muscular system of birds, that the writer undertook an exhaustive study of the muscles of the Raven (Corvus cor ax vi PREFACE. sinuatus) ; and the work here placed before the reader, with its eighty and odd figures, is the outcome of those investigations. With regard to my nomenclature of the muscles I have here described and figured, I have been guided by such brief chapters as are devoted to this subject and which appear in the published scientific memoirs of such excellent authorities as Owen, Carus, A. Milne- Edwards, Huxley, Garrod, Forbes, Selenka, Coues, Fttr- bringer, and Gadow ; but when I have been in doubt, and these authorities failed to assist me, I have en- deavoured to bestow upon the muscle a suitable name. The student must bear in mind, too, that many other birds possess muscles which are not to be found in the Eaven ; in some special cases I have alluded to these. On the other hand, the muscles, even in the represen- tatives of the same species, may vary in certain in- dividuals to some extent. This fact has long been appreciated by anthropotomists. Gadow's work upon the muscles of birds, which appeared in Bronn's Thier-Rcichs, is an admirable con- tribution to the general subject ; but it is by no means a work that meets the general want, and possesses the disadvantages of being but meagrely illustrated, and of having appeared in German, in a work of limited cir- culation. Notwithstanding this, I am quite sure my reader will feel grateful for my having incorporated Gadow's synonymy in footnotes in the present volume, as they cannot fail to be anything but the most useful adjunct to a guide to avian myology. In arranging and grouping the elements of this PREFACE. vii system, it is to be hoped that the writer's plan will be found to be a convenient and helpful one : it was his chief aim throughout, next to accuracy and clearness of description, to make it so. In choosing the Raven for our subject, it was done in view of the fact that it is a large representative of a very numerous and cosmopolitan family of birds, the Corvidce ; so that, in almost any part of the world, a variety of birds become available whose muscular sys- tems can be studied by the aid of the present volume. It is hardly necessary to add that Crows of all descrip- tions, Jays, Orioles, and a host of others, all fall within this category. It has its advantage, too, for the teacher and the student at the biological laboratory ; for the former can use as his subject the larger and more advan- tageous specimens, as the Ravens or Crows, while the latter can confirm the instructions of the former, at home, upon any of the smaller varieties of the Corvidce, such as the Jays or Rooks. As his investigations in the myology of vertebrates progress, three lines for improvement, in so far as our knowledge of the muscular system of birds is concerned, will force themselves upon the student. In the first place, we still remain very ignorant of the details of this system in a great many important types of birds ; secondly, an ever-pressing demand is evident, to fix the homologies of muscles in the Vertebrata, and conse- quently to bring so far-reaching a knowledge of this department of research to our assistance as to be enabled to give the same name to the same muscles, accurately, throughout the vertebrate series ; finally, a simple, viii PREFACE. scientific, and euphonious nomenclature is very much to be desired. As an index of our present status with respect to our knowledge of the muscles of birds, it is hoped that the volume here offered will faithfully repre- sent it, but its writer trusts that in future works he may lend his assistance to the improvement of all the lines above indicated. To this end, he will be thankful for any suggestions that may be useful should the present volume go to another edition, and good criticism of the same will be welcomed from any quarter. Already, the question of ncuro-myology, or the nomen- clature of muscles based upon their nerve-supply, has made considerable progress in modifying our views in that direction, and although I am convinced that it by no means always furnishes an invariable guide to follow, still its great usefulness is not to be ignored. With no little interest I have read the " Neuro-myology " of Coues and Shute (New York Medical Record, July, 1887), and am compelled to admire the masterly manner in which they have instilled new life into an old theme. Unfortunately, the same muscle as represented in different types of the vertebrate series, is not always served by the same nerve, and this would stand in the way of a general grouping and a universal neuro- myological nomenclature upon any such a basis. To those of my readers who are familiar with German, the best works I can recommend to be consulted in the present connection are the very excellent treatises of Selenka and Gadow in Bronn's Klassen des Tlder-Reichs; and that superb monument to avian morphology, the Untersucliunyen zur Morphologic und Systematik der PREFACE. ix Vogel of Max Fiirbringer. To Professor Gadow lam indebted for a great many titles of works which I have incorporated in the bibliography which is found at the end of this volume ; still, I have personally examined the majority of books there enumerated. English and American literature, as I have already stated, furnishes us with no good handbook to the subj ect. Frequently, an author, as he closes his prefatory remarks, finds that he has a host of helpful friends to whom his thanks are due for assistance rendered : it proves to be the exception in the present instance, for all of the material used was collected by myself ; all the dissections were made by myself ; all the descriptions are in my own handwriting ; and the drawings were all drawn directly from the dissections by myself. Still it gives me pleasure to remember here rny friend Dr. J. L. Wortman, the biologist of the United States Army Medical Museum, who, several years after this volume was written, carefully passed over with me the mus- culature of the shoulder-joint in birds, and verified my dissections upon the Raven, comparing them with similar studies he was at the time engaged upon in the Raptores, Further it gives me pleasure to express my thanks to .Dr. G. Brown Goode, of the United States National Museum, for having upon a number of occasions furnished me with the means of preserving my somewhat extensive material, and that, too, when my labours upon the present volume were being prosecuted in New Mexico, between two and three thousand miles from civilization, the libraries, and the x PREFACE. museums ; and that at a time when the operations of a short-sighted and destructive policy which influences our Government in its attitude toward scientific inves- tigators came quite near placing the researches herein tendered to my readers and collaborators in anatomy, beyond the pale of publication. E. W. S. TAKOMA, D.C. August 20, 1889. CONTENTS. PAGE PREFACE V LIST OF ILLUSTRATIONS xiii INTRODUCTION 1 THE DERMAL MUSCLES 3 THE MUSCLES OF THE HEAD 15 THE MUSCLES OF THE TONGUE 23 THE MUSCLES OF THE AIR PASSAGES 43 THE MUSCLES OF THE EYE AND EAR 53 THE MUSCULATURE OF THE EAR 62 THE MUSCLES OF THE UPPER EXTREMITY 66 THE MUSCLES OF THE LOWER EXTREMITY 155 THE MUSCULATURE OF THE TRUNK 258 BIBLIOGRAPHY 319 INDEX 329 3 9 3 3 fi LIST OF ILLUSTRATIONS. [NoTE : — All the figures illustrating this work were drawn by the author, and with but few exceptions, where they have been copied from the drawings of other anatomists, were made directly from the recent dissections, and in the vast majority of cases the size of life.] PACE 1. Side view of the skull of the Baven, showing points of origin and insertion of muscles .......... 7 2. Superior aspect of skull of the Eaven, showing points of origin and insertion of muscles .......... 11 3. Showing points of attachment of muscles on the basal aspect of the skull in the Eaven ......... 17 4. The posterior aspect of the skull in a Eaven, showing origin and insertion of the muscles ........ 19 5. Side view of the mandible in Corvus corax sinuatus, show- ing the areas of muscular origin and insertion .... 21 6. Corvus corax sinuatus, the mandible from beneath, showing points of attachment of muscles ......... 23 7. Corvus corax sinuatus, dissection of muscles of the head, seen upon right lateral view .......... . . 28 xiv LIST OF ILLUSTRATIONS. FIG. PAGE 8. Corvus corax sinuatus, oblique view of bones of shoulder- girdle, showing areas of attachment for muscles ... 31 9. Corvus corax sinuatus, the hyoid arches from beneath, showing points of attachment of muscles 31 10. Corvus corax sinuatus, superior view of bones of the upper larynx, showing points of attachment of muscles ... 31 11. Corvus corax sinuatus, the muscles of the head, seen from beneath 32 12. The tongue and salivary glands of a Woodpecker (after Owen) • 44 13. Front view of the lower larynx of a Raven, showing muscles (after Owen) 44 14. Side view of the lower larynx of a Raven, showing muscles (after Owen) „ 44 15. Lower larynx of a Parrot (after Owen) 44 \ 16. Muscles of organ of hearing in an Owl (after Owen) . . 44 17. Corvus corax sinuatus, its hyoid arches from beneath, showing points of muscular attachment 46 18. Corvus corax sinuatus, its hyoid arches from above, show- ing points of muscular attachment 46 19. Corvus corax sinuatus, the musculature of its windpipe . . 50 20. Corvus corax sinuatus, the head from above, with roof of orbit removed 54 21. Mesial aspect of an eye of a Goose (after Owen) .... 55 22. Corvus corax sinuatus, side view of skull to show origin of eye-muscles in the orbit 56 LIST OF ILLUSTRATIONS. xv FIG. PAGE 23. Corvus corax sinuatus, muscles at the back of the eye, dis- sected 60 24. Corvus corax sinuatus, right lateral view of the skeleton of the trunk, showing areas of muscular attachment . 68 25. Corvus corax sinuatus, the sternum from in front, showing areas of muscular attachment 71 26. Corvus corax sinuatus, superficial muscles, anterior aspect, of the upper extremity, as far as the elbow 77 27. Corvus corax sinuatus, anconal aspect of right humerus, showing where the muscles arise and are inserted ... 83 28. Corvus corax sinuatus, proximal view of head of humerus, to show muscular attachments 83 29. Corvus corax sinuatus, palmar aspect of humerus, to show points of muscular attachment 83 30. Corvus corax sinuatus, radial aspect of humerus, to show points of muscular attachment 83 31. Corvus corax sinuatus, ulnar aspect of humerus, to show areas of attachment of muscles 83 32. Corvus corax sinuatus, anterior aspect of some of the muscles of the upper extremity 89 33. Corvus corax sinuatus, superficial muscles of the upper ex- tremity in the region of shoulder and dorsum .... 97 34. Corvus corax sinuatus, oblique left lateral view of the second layer of muscles of the upper extremity, being those of the dorsum and arm 103 35. Corvus corax sinuatus, left oblique view of the body, dis- sected to show the deep muscles about the shoulder . . 107 xvi LIST OF ILLUSTRATIONS. FIG. PAGE 35 bis. Axillary muscles of the side of Gallinula chloropus (after Garrod) 110 35 ter. Outer aspect of the axillary muscles of the right arm in a specimen of the Mourning Dove (Zenaidura macroura) 110 35 quat. The plucked body of a bird, drawn to show where to make the incision to expose the patagial muscles . . 112 35 quin. Muscles of the patagium in Icterus vulgaris (after Garrod) 113 35 sex. Muscles of the patagium in Progne subis 114 36. Corvus corax sinuatus, bones of forearm and hand, showing muscular attachments 121 37. Corvus corax sinuatus, radial aspect of left ulna and radius, showing where muscles are attached 126 38. Corvus corax sinuatus, outer aspect of left forearm and pinion, showing the position, origin, and insertion of the superficial layer of muscles 131 39. Corvus corax sinuatus, inner aspect of left forearm and pinion, showing the position, origin, and insertion of the superficial layer of muscles 140 40. Corvus corax sinuatus, outer aspect of forearm and hand, showing relative position, origin, and insertion of the deep layer of muscles 143 41. Corvus corax sinuatus, inner aspect of forearm and hand, with the superficial layer of muscles dissected away, showing the origins and insertions of the deep layer . 145 42. Corvus corax sinuatus, anterior aspect of the bones of the left hand, showing origin and insertions of muscles . . 152 43. Corvus corax sinuatus, ulnar aspect of the bones of the left hand, showing origin and insertions of muscles . . 152 LIST OF ILLUSTKATIONS. xvii FIG. PAGE 44. Corvus corax sinuatus, posterior aspect of the bones of tin- left hand, showing where muscles are attached .... 152 45. Corvus corax sinuatus, anterior aspect of left femur, show- ing where the muscles are attached to it 167 46. Corvus corax sinuatus, posterior view of left femur, show- ing points where muscles arise 167 47. Corvus corax sinuatus, inner aspect of left femur, showing areas where muscles are attached 167 48. Corythaix erythrolopha, dissection of its thigh muscles (after W. A. Forbes) 17:) 49. Corvus corax sinuatus, skeleton of left posterior extremity, showing muscular areas of attachment 178 50. Corvus corax sinuatus, head of its tibia (enlarged), to show points of origin of muscles 178 51. Corvus corax sinuatus, left tibia and fibula, showing mus- cular attachments 187 52. Corvus corax sinuatus, anterior view of left leg bones, showing where their muscles are attached 187 53. Corvus corax sinuatiis, left leg bones seen from behind, showing muscular attachments 187 53 bis. Right three-quartering view of the pelvis of a speci- men of the Piiion Jay {Cya/nocephalus cyanocephalus), showing the origin of the obturator inter mis muscle of the right side, o.i. Enlarged 1(J2 54. Corvus corax sinuatus, visceral aspect of pelvis and tail vertebra?, showing the obturator muscle and its origin . I'.Jti 55. Corvus corax sinuatus, anterior view of tarso-metatarsue, with muscular areas shown upon it 201 56. Corvus corax sinuatus, posterior view of tarso-metatarsus, showing areas of muscular attachment 20 i xviii LIST OF ILLUSTRATIONS. FIG. PAGE 57. Corvus corax sinuatus, summit of tarso-metatarsus, seen from above 201 58. Corvus corax sinuatus, basal joint of hallux, seen upon superior view 201 59. Corvus corax sinuatus, basal joint of hallux, seen from beneath 201 GO. Corvus corax sinuatus, skeleton of left foot, seen from be- hind, showing the areas and points of attachment of muscles 206 61. Corvus corax sinuatus, outer aspect of the skeleton of left pelvic limb, showing superficial muscles of thigh and leg 207 62. Corvus corax sinuatus, skeleton of left foot, designed to show where the tendons pass 210 62 bis. Outer aspect of the right pelvic limb of Geococcyx calif ornianus 213 63. Corvus corax sinuattis, outer aspect of left pelvic limb, showing second layer of muscles . , 216 63 bis. Pelvic limb, right side, of Geococcyx calif ornianus ; the superficial layer of muscles removed 221 64. Corvus corax sinuatus, outer aspect of left pelvic limb, showing third layer of muscles of thigh and leg . . . 224 64 bis. Pelvic limb, right side, of Geococcyx calif ornianus, showing muscles of the third layer, and the ambiens . 231 65. Corvus corax sinuatus, outer aspect of left pelvic limb, showing the fourth or deepest layer of muscles of thigh and leg 236 65 bis. Pelvic limb, right side, Geococcyx calif ornianus. show- ing the deepest layer of muscles LIST OF ILLUSTRATIONS. xix FIG. PAGE 65 ter. Right foot of Megalcema asiatica, showing an arrange- ment of the plantar tendons 239 65 quat. Left foot of Galhis bankiva 239 65 quin. Right foot of Apteryx 239 66. Corvus corax sinuatus, dorsal aspect of the skeleton of the trunk, designed to show the areas where muscles are attached to it 260 67. Corvus corax sinuatus, cervical vertebra?, showing where muscles are attached to them 269 68. Corvus corax sinuatus, cervical vertebrae, showing whefre muscles are attached upon their lower aspects .... 269 69. Corvus corax sinuatus, side view of cervical vertebra, showing points of origin and insertion of muscles . . 269 70. Corvus corax sinuatus, dissection of muscles of head and neck, seen on lateral aspect 274 71. Corvus corax sinuatus, six leading cervical vertebrae (en- larged), side view, showing deep-seated muscles . . . 280 72. Corvus corax sinuatus, dorsal view of sixth, seventh, and eighth cervical vertebrse, showing the deep muscles that are attached to them 280 73. Corvus corax sinuatus, side view of trunk, showing dissec- tion of superficial muscles attached to it 293 74. Corvus corax sinuatus, side view of the trunk, showing the deep layer of muscles 300 75. Corvus corax sinuatus, muscles of the diaphragm . . . . 313 76. Corvus corax sinuatus, visceral aspect of pelvis and skeleton of the tail, showing the muscles attached to them 317 THE MYOLOGY OF THE RAVEN (Corvus cor ax sinuatus). INTRODUCTION. IN all highly specialized birds, and more particularly in those possessing great power of flight, such as the Oscines, the Rapt ores, and many of the Anseres, the various muscles are chiefly noted for their density, their dark carmine colour, and the distinctness between the fleshy portion and the tendinous. These char- acteristics are best seen in those groups of muscles which are brought into play during flight. As a rule, through- out the system, the tendons are very firm, dense, and of a bright pearly white colour ; and these, in the limbs especially, show a marked tendency to ossify. Having obtained a fine adult Eaven (or Crow), showing but few or slight injuries incident to its cap- ture, and having completely and carefully plucked the specimen, it is to be immersed in 80 per cent, alcohol for at least forty-eight hours. The student then must supply himself with a large delf platter, for a dissecting tray ; a grooved director, a set of hooks and chain, a pair of wide-aperture spring forceps, and finally, three or four suitable scalpels of various sizes. Everything being in readiness, the first object of B 2 THE MYOLOGY OF THE RAVEN. our dissection will be to demonstrate and expose the cutaneous system of muscles, or the dermal muscles. The dermal muscles are principally of two kinds : viz. the dermo-osseous, and the true dermals. The first- named have their origin on some part of the skeleton, and their insertion in the integuments ; while the second kind both arise and are inserted in the skin or some of its appendages. We never find all the known dermal muscles in any one form ; they vary with certain characteristics of the bird. The Peacock has a special dermal muscle to act upon the gorgeous fan which it spreads, and is com- posed of the feathers of the lower part of the back. Other birds having large crests, and peculiar skin developments about the head, which require special movements, possess the appropriate dermal muscles to operate upon them. Again, all birds possess an enormous system of minute muscles divided up into an infinite number of fasciculi, to harmoniously act upon the feather- quills, and collectively agitate the plumage. These are quite conspicuous in the Raven, but will not be especially dwelt upon. With an ordinary lens their action may be studied with comparative ease in one of the large quill- butts of the pinion, or tail. In the Raven the apteria are entirely devoid of muscles, and even the other dermal muscles often appear to turn out of their usual direction to avoid these tracts. The muscles may be arranged, according to the usual divisions of the body, into those of the cutaneous system ; those of the head and neck ; those of the trunk ; those of the upper extremity ; those of the lower extremity ; and those devoted to the organs of special sense. I. THE DERMAL MUSCLES. 1. TRUE DERMAL MUSCLES. 1. The dermo-frontalis. 4. The dermo-dorsalis. 6. The dermo-tensor patagii. 12. The dermo-humeralis. 13. The dermo-pectoralis. 2. DERMO-OSSEOUS MUSCLES. 2. The circumconcha. 3. The dermo-temporalis. 5. The platysma myoides. The dermo-cleido dorsal is. The cleido-trachealis. 9. The dermo-spinalis. 10. The dermo-iliacus. 11. The clermo-ulnaris. l. 8. 1. The dermo-frontalis.1 — Carry an incision through the skin down to the bone, on the superior aspect of the head, parallel and close to the base of the upper mandi- ble, extending completely across. Next, from the outer 1 Selenka, in his classical work devoted to the anatomy of birds (Bronn's Klassen und Ordnungen des Thier-Reichs, Sechster Band. IV. Abth., Vogel : A ves. 3 u. 4 Lieferung et seq.}, touches but lightly upon the dermal system of muscles in the Class ; while even those subsequent writers, Fiirbringer and Gadow, in their well-nigh ex- haustive memoirs in the same field, have by no means given us a complete history of this part of the myological system in Aves (Bronn's Klassen, vi. Band, 7-22 Lieferung]. Such being the case, I find but few authors with whom I can compare notes, bibliographical or otherwise, upon the thirteen muscles described above as considered by me as belonging to the dermal system in Corvus. And I submit them for the most part as they were found to exist in the Raven, B 2 4 THE MYOLOGY OF THE RAVEN. end of this make an incision backwards down to the skull, and posteriorly to well expose the muscles in the upper part of the neck. This straight cut should pass about half a centimetre to the inner side of the upper eyelid of the same side. Reflect the flap of integu- ment thus formed, covering the top of the skull, and carefully examine the under side of it in the median line, where it overlies the frontal region. In old male Ravens, I have here found a true dermal muscle, some 3 centimetres long, and a few millimetres wide, closely attached to the skin. So far, it has not been observed by me in female birds. By its contraction, the median feathers on the top of the head are made to lie very flat ; at the same time those immediately above either eye are elevated, thus giving rise to lateral crests, which are quite well marked. In a captive Raven, an old adult male, I have seen the bird during certain moods make these crests stand up so as to be very evident, not to say conspicuous. 2. The circumconcha.— -This is a dermo-osseous muscle which surrounds the periphery of the ear-conch. To expose it, join the longitudinal incision we have already made, and carry the scalpel just through the integument completely around the ear, a few millimetres without its thickened margin ; — then dissect carefully up from all simply inviting attention to the fact that my dermo-temporalis appears to be the second division of the M. CUCULLAEIS of Gadow ; the dermo-dorsalis being also a part of the same ; while the platysma myoides of my list is the first division of the m. cucullaris of the same writer ; and finally, my dermo-tensor patagii is the PAUS PROPATAGIALIS of the M. cucuLLAEis of Furbringer. The skin muscles in the neck of birds have been quite extensively divided up by Gadow and Fiirbringer, described under a superficial and deep set, and in the main as constituting various parts of their m. cucullaris (Bronn's Klassen, vi. Band, 11 u, 1 2 Lieferung, p. 214). THE DERMAL MUSCLES. 5 sides towards it. As we detach the thickened portion just referred to, it will be found that it contains a dermal circular muscle, closely attached to the skin, but arising1 in an evident bundle of muscular fibres which have their origin at the outer terminus of the supraoccipital crest (Fig. 7, c c). The ear-conch is further supported by two ligaments, attached at anterior and superior points. 3. Tlw dermo-temporalis. — Extend the longitudinal incision down the back of the neck to a point between the clavicular heads, carrying it just through the skin, and a few millimetres to the left of the median line. Care- fully reflect back the entire flap, removing the skin from the throat and the anterior portion of the chest ; and the alar and parapatagial duplicatures of the skin are also to be laid open. A number of dermal muscles are now exposed. One of the most important of these is the dermo-temporalis. On either side it is found to arise by a broad tendinous attachment from a small depres- sion just above and anterior to the temporal fossa. The lower end of this attachment extends down over the sphenotic process, being but slightly wider than it above. From this origin the fibres of the muscle pass directly backwards as a rather broad flat bundle, and make some slight tendinous attachments with the temporal, which it covers. Once clear of the skull, this muscle, as a rather broad and thinnish band of delicate fibres, and intimately connected with the skin, passes directly down the side of the neck, being separated dorsad by quite an interval from the fellow of the opposite side, while anteriorly its margin tends to blend with the fibres of the cleido- o trachealis ; indeed a few of its fibres may run in to join this muscular fasciculus. Opposite the shoulder- joint in front the lower ends of the muscular fibres of the dermo- temporalis are lost upon the skin, or blend with the 6 THE MYOLOGY OF THE RAVEN. fibres of the dermo-tensor patagii (to be described further along), or else, as I say, a few of them seem to merge with the cleido-trachealis. This muscle acts as a tensor of the lateral cervical integuments, and through its O 7 O connection with the dermo-tensor patagii, as an auxiliary to the tensor patagii longus. From such information as I have at hand at the present writing, I would say that the muscle I here describe corresponds to the temporo-alaris of Viallane, or at least to the upper portion of the temporo-alaris of that writer. It has also received other names at the hands of anatomists, as may be seen by consulting their works, or such as deal with the myology of birds. 4. The dermo-dor salis. — I give the long muscular strip that we find in the Raven, in the median line, running down the neck and back, this name. It is most prominent in the middle of the neck, where it is inclosed in a fold of the integument. It gradually becomes lost as we approach the occiput, as it in like manner spreads out and disappears over the caudal region. Much fat may overlie it, which must be carefully dissected away to bring the muscle into view. By its contraction the feathers along the median line of the dorsum and neck are raised, which action is assisted by the preceding muscle. 5. The platysma myoidcs. — This muscle is fairly well developed in the Raven, but requires careful dissection to bring it into view. It arises on either side, from the lower margin of the ramus of the jaw, below the ramal vacuity. From these points it spreads out as a very thin, fan-like sheath, closely attached to the skin, to meet in a faint raphe in the median line. It will be seen that the common muscular layer thus formed, materially assists in supporting the lingual apparatus and the upper THE DERMAL MUSCLES. 7 larynx, which are the chief structures found immediately above it. When this muscle contracts, these parts will be compressed and elevated. 6. The dermo- tensor patagii. — That duplicature of the common integument, of a triangular form, which is found in the Raven, as in other birds, between the root of the neck and the top of the shoulder, may be designated as the parapatagium, in contradistinction to the pro- patagium, or the alar integumental duplicature. Lying within the free marginal fold of the parapatagial FIG. 1. — Right lateral view of the skull and mandible of Cornrs cor ax sinuntus, designed to show the origin and insertion of the muscles of the head, &c. Life-size, by the author, cc, origin of the circumconcha. duplicature in the Raven, we discover a well-developed bundle of muscular fibres, the mesial ends of which spread out, to either become, as a few of them do, inserted into the skin upon the antero-aspect of the root of the neck, or else pass obliquely upwards to blend with the fibres of the dermo-temporalis. This muscle I designate as the dermo-tensor patagii, and externally its 8 THE MYOLOGY OF THE RAVEN. fibres converge, and opposite the outer carneous extremity of the tensor patagii longus they become converted into a small and delicate, though strong tendon, which soon thereafter blends with the tendon of the tensor patagii longus, and in its action plays the part of an auxiliary to it. The dermo-tensor patagii I have already alluded to in various publications, and find in my dissection of birds generally that it is quite a variable muscle ; and were these variations all known and appreciated, I am confident that they would be characters of considerable taxonornic value. This muscle seems to correspond to the " pars propatagialis musculi cucullaris " of Flirbringer and Gadow, and has by several writers been described as occurring in the species representing a variety of orders of birds. 7. The dermo-cleido dorsalis (Fig. 8). — A beautiful pair of muscles exist in the Eaven upon which I- have bestowed this name. Either one arises from the upper and mesial aspect of a clavicular limb, to the extent shown in the drawing. As the muscle passes to the integument, it becomes closely attached to it, is directed over the shoulder-joint and scapular region in front, as three distinct fasciculi, diverging in a fan-like form. The extremities may meet in the median line of the dorsum to merge with the dermo-dorsalis. It is very evident that the contraction of these muscles will brace the skin over the fore-part of the back, while if, on the other hand, they act from their integumental attachment, they may aid to a limited extent in the act of inspiration.1 1 These muscles seem to fulfil, in part, the function of the dermo- transversalis of Owen, which I fail to discover in the Eaven. This eminent authority describes this muscle for the Apteryx in the Jollowing words :— " The skin covering the dorsal aspect of the lower THE DERMAL MUSCLES. 9 8. The cleido-tracheales.- -These muscles are highly developed in the Kaven, and seem to take the place of the sterno-maxillaris of Owen.1 Each arises from a two-thirds of the neck, besides being acted upon by the constrictor colli, is braced down by a thin stratum of oblique and somewhat scattered fibres, dermo-transversalis, which take their origin by fascise attached to the inferior transverse processes of the sixth to the twelfth cervical vertebrae inclusive ; the fibres pass obliquely upward and backward, and are inserted by a thin fascia into the median line of the skin covering the back of the neck " (Anat. of Verts., vol. ii., p. 111). The dermal system of muscles is highly developed in the Apteryx, and this may account for the absence of the sterno-cervicalis in such a form as the Raven, or its occurrence in a very rudimentary con- dition, which I failed to discover. The same author says : — " The sterno-cervicalis arises fleshy from the posterior incurved angular process of the sternum, from the ensiform prolongation and middle line of the outer and posterior surface of the same bone. The fibres pass forward, and, diverging in gently-curved lines, ascend upon the sides of the broad base of the neck, and are inserted by a thin but strong fascia into the median line of the dorsal integument. This muscle is a line in thickness at its origin, but becomes thinner as it expands ; the anterior part is covered by the posterior fibres of the constrictor colli" (loc. cit., p. 110). Since writing this footnote I ascertain that the sterno-cervicalis of Owen is considered by Gadow to represent the deep layer of his mi. cucullaris (Bronn's Klassen des Tkier Reichs, vi. Band, p. 214). 1 " The sterno-maxillaris [in the A'pUrix\ appears at first view to be the anterior continuation of the preceding [sterno-cervicalis], but is sufficiently distinct to merit a separate description and name. It arises fleshy from the anterior part of the middle line of the sternum, passes directly forward along the under or anterior part of the neck, expanding as it proceeds, and gradually separates into two thin symmetrical fasciculi, which are insensibly lost in the integu- ment covering the throat and angle of the jaw. It adheres pretty closely to the central surface of the constrictor colli, along which it passes to its insertion. It retracts the fore-part of the skin of the neck, and also the head. Each lateral portion acting alone would incline the head to its own side ; the whole muscle in action would 10 THE MYOLOGY OF THE EAVEN. small circumscribed area situate upon the antero-inner aspect of the middle of either limb of the furcula as a rounded, though not large, bundle of muscular fibres. They take their course directly up the neck, separated by quite an interval. About the middle of their path, they each flatten out and become intimately attached to the skin and the dermo-temporalis muscle. Further along, they become gradually narrower again, and are finally inserted, touching each other by their inner borders, on the anterior aspect of the superior larynx, the trachea, and the skin over these parts. It is only for about their middle thirds that they may be con- sidered as true dermal muscles, and thus account for their appearance in the present category. By their acting in common, or each in turn, movements of the parts would result similar to those described by Professor Owen for the sterno-maxillaris (see footnote, anted). The longitudinal incision which we made down the back of the neck must now be extended, passing only through the skin, to the distal tip of the pygostyle. bend the neck ; but the movements of the head and neck are more adequately and immediately provided for by the appropriate deeper- seated muscles, and the immediate office of the present muscle is obviously connected with the skin. Nevertheless, in so far as this muscle acts upon the head, it produces the same movements as the xterno-mastoideus in Mammalia " (loc. cit., p. 111). Since writing the footnote just quoted from Owen, 1 have ascer- tained (Bronn's Klassen des Thier-Reichs, vi. Band, pp. 214, 215) that Professor Gadow considers the constrictor colli of Owen to be the superficial layer of the muscle called the cucullaris by Professor Fiirbringer and adopted by himself, while the dermo-spinalis of Owen constitutes the third division of the same muscle, or the m. cucullaris, pars propatagialis, of Fiirbringer, which, as I have above remarked, is my dermo-lensor patayii. — R. W. S. THE DERMAL MUSCLES. 11 Reflect back on either side the integumental flaps, as far as the sides and the limbs. Several muscles of the cutaneous system are now exposed in this region. 9. The dermo-spinalis.— -T\ns> delicate muscle is but FIG. 2. — Superior aspect of the skull of Raven, adult <$ , life-Mze. Mandible removed. Shows the upper edge of the insertion of the temporal muscle, and that part of the masseter which arises on the zygoma. feebly developed in the Raven, but a little staining in old males will usually bring its fibres into view. It arises in an attenuated fascia from the crests of the 12 THE MYOLOGY OF THE RAVEN. neural spines of the first, second, and third dorsal vertebrae, the fibres pass directly outwards, closely attached to the skin, in rather a broad pale stratum, to be lost over the scapular region on either side of the body. 10. The dermo-iliacus is a parial muscle, either one of which arises fleshy from the inner angle of the emar- ginated portion of the antero-dorsal border of the ilium. The fibres pass directly forwards, as a narrow ribbon, to spread out as a thin integumental layer, to be lost over the region of the shoulder-blade. These last two muscles acting from their points of origin would so pull the skin as to cause the feathers attached to it to lie flat, or closer to the body, over the parts where they are severally distributed. In this way they antagonize some of the muscles described above, as, for example, the dermo-dorsalis. 11. The dermo-ulnaris l is exposed by still further reflecting the skin. It is a very prominent muscle, and 1 This muscle is the PARS METAPATAGIALIS of the M. SERRATUS SUPERFICIALIS s. THORACi-sCAPULARis of Fiirbringer, and also of Gadow (Bronn's Klassen, vi. Band, p. 221), and represents the tensor membrance posterioris alee of Wiedemann and Tiedemann, of Riidinger, of Selenka, and of Carlsson, while Schopss described it in part as the m. plicae alaris posterioris. Of it Gadow has said :— "III. Pars metapatagialis. Dieser Theil ist nach Fiirbringer als aberrirende zur Haut gehende Lage des Serrat. post, aufzufassen. Er entspringt mit zwei oder drei, selten mit nur einer Zacke zusammen mit den Biindeln der Pars post, serrati von den Rippen, heftet sich an die Hautduplicatur zwischen Oberarm und Rumpf und verliert sich an den oberen Schwungfedern zweiter Ordnung. Der Muskel is demnach ein Theil des weiter unten als M. meta- palagialis zusammengefassten Flughautspanners. Er findet sich bei Gallus, Anser, Cygnus, Fulica, Otis, Psittacus, Raptores, Cor- vidse, u.s.w., fehlt aber den Spheniscidse, Tubinares, Ratitse " (Bronn's Klassen, vi. Baud, p. 224). THE DERMAL MUSCLES. 13 one of the most conspicuous of the cutaneous system. It arises by a thin fascia from the outer aspects of the third and fourth true vertebral ribs, at the bases of their epipleural appendages, and from the fascia between them. From this point it passes forwards and upwards as a thick muscular bundle, loosely attached to the skin, until it arrives in a point at the inner end of the integu- mental duplicature behind the humerus. Here it be- comes a small and slender tendon lying between these skin flaps in the line of their posterior margin, as far as the elbow-joint, where the tendon spreads out to become attached to the fascia in the locality, and covering the olecranon of the ulna. By extending the elbow-joint it assists in elevating the wing.1 12. The dermo-humeralis 2 arises as a broad but 1 Owen describes for the Apteryx a dermo-costalis which " arises fleshy, from the costal appendages of the seventh and eighth ribs. The fibres pass forward and join those of the preceding muscle [dermo- iliacus] to be inserted into the scapular integument " (Anat. of Verts., vol. ii., pp. Ill, 112). I made several special dissections for the very purpose of finding this muscle in the Raven, but my investiga- tions lead me to believe that it does not exist in our present subject. 2 Fiirbringer and Gadow have divided the M. PECTORALIS into three parts, and the dermo-humeralis as here described for the Raven corresponds to the third part, or the PARS ABDOMINALIS (Fiirbringer). Gadow presents us with the synonymy of the dermo-humeralis as follows : — " III. Pars abdominalis (Fiirbringer). Subcutaneus abdominalis. Wiedemann, Tiedemann, § 100. No. 5. ,, „ Watson, p. 55. Subcutaneus thoracis. Tiedemann, § 100, No. 4. Prechtl, § 71. Ohne Namen erwahnt. Schopss, p. 112. Dermo-humeralis. Owen, p. 24, Panniculus carnosus (second portion). Reid, p. 139. Muscle des parures. Gervais et Alix, p. 401. Watson, p. 81." 14 THE MYOLOGY OF THE RAVEN. barely perceptible fan-like muscle in the abdominal integument. This is soon gathered, as it passes forwards and upwards, towards the head of the corresponding humerus, into a decided, long narrow fasciculus of fibres, to be finally inserted by a very pretty little fan-like expansion of thin glistening fascia into the tendon of the pectoralis major just below its insertion. In the Apteryx the dermo-humeralis " is inserted fleshy into the proximal part of the humerus " (Owen). In either case it depresses the humerus in the last-named- bird by acting directly upon the bone, while in the Raven it is an auxiliary to the great pectoral muscle. 13. The der mo -pectoralis is a muscle that corre- sponds to the dermo-dorsalis of the back, and is simply the evident muscular stratum underlying the feather- quills of the tracts of these appendages, that are found on either side of the robust chest of this bird, running in the longitudinal direction. Either of these muscles disappears anteriorly over the orio-in of the cleido-trachealis, while behind their ter- o minal fibres merge imperceptibly into the integument after passing the hinder tips of the postpubic elements of the pelvis. Acting from the anterior skin insertion, these muscles raise the feathers of the chest, the action being reversed by the muscle contracting from the opposite extremity. II. THE MUSCLES OF THE HEAD. INCLUDING THE MUSCLES OF THE LINGUAL APPARATUS, TRACHEA, AND THOSE OF THE EYE AND EAR. DIVIDE the skin completely around the entire beak, at its base ; divide the platysma myoides close to its origin, on either side, and allow its gular portion to come away with the integument as it is removed ; in like manner, divide, on either side, close to their origins, the circum- conchae and dermo-temporalis. Carefully reflect back- wards the entire skin, so as to expose the neck for at least its upper third. Open the bird's mouth to its full extent, and pack sufficiently with soft tow, so as to render the muscles of the tongue and trachea more prominent. The muscles here to be examined are the intrinsic muscles of the head, and are in no way attached to the vertebral column. They are the following :— 14. The temporal. IS. The pterygoideus interims. 15. The masseter. 19. The pterygoideus externus. 16. The biventer maxillae. 20. The digastric.1 17. The entotympanicus. 1 This group of muscles (14-20 inclusive) are presented by Gadow in his well-known memoir on the morphology of Aves in Bronn's Klassen, vi. Band, pp. 318-325, where they are illustrated by 16 THE MYOLOGY OF THE EAVEN. 14. The temporal.- -To thoroughly expose this muscle we must divide the strong; lateral ligament of the o o jaw, which is attached above the tip of the squamosal process, and below to the outer side of the articular end of the mandible. The dense fascia encasing the temporal should also be largely dissected away. The bulk of this fan-shaped muscle will be found attached to, and occupying the entire temporal fossa. Anterior to this, some of its more fleshy fibres arise from the mesial side of the sphenotic process, and the adjacent wall of the orbit. From this extensive origin the fibres converge as they pass downwards and forwards, blend more or less completely with the fibres of the masseter as they come opposite to them, to finally become tendinous, to be inserted in the coronoid process upon the superior rarnal margin of the mandible. 15. The masseter (Figs. 1 and 7). — This muscle, which may be considered a powerful auxiliary to the one just described, is in the Kaven divided into two distinct portions. The greater mass arises by a broad and thin tendon from the entire length of the bony ridge above the auditory entrance, and the squamosal process numerous handsome and useful figures on plates, and an extensive synonymy is given, the latter being somewhat too extensive to reproduce in the present connection. He divides his M. BIGASTRICUS s. DEPRESSOR MANDiBUL^: into three portions (a, Aussere Portion ; b, Mittlere Portion ; and c, Innere Portion), and separately defines them. The temporal has also been somewhat similarly dealt with, having been divided into four portions, with an accessory part. The pterygoidal muscles are given under a single caption, the MM. PTERYGOIDEI. Numerous prominent writers have been omitted in so far as the synonymy goes, though the subject of these head- muscles has been carefully handled by the author in question. In my description above, I have essentially adopted (for the present) the nomenclature of Owen (Anat. Verts., vol. ii.), though subsequent dissections may incline me to alter or abandon it. THE MUSCLES OF THE HEAD. 17 which extends it. It also has a fleshy attachment to the outer aspect of the body of the quadrate bone. As it passes downwards and forwards beneath the zygoma, it FIG. 3. — Under side of skull of Raven. Life-size. Shows the, attachment of the muscles found on this aspect of the skull. By the author. blends with the fibres of the temporal, and makes its first insertion by a tendinous slip to a small tubercle, situated on the upper border of the jaw, behind the c 18 THE MYOLOGY OF THE RAVEN. coronoid process. The great bulk of this division of the muscle, however, passes on to be inserted, fleshy, on the outer side of the ramus of the mandible, nearly as far forward as the horny beak, while behind it is bounded by the prominence of the articular extremity (Fig. 7). Quite a dense fascia encases this division of the muscle. The smaller part of the masseter arises, rather fleshy, from the side and under border of the hinder fourth of the zygoma. This auxiliary and spindle-shaped slip terminates behind in a small, though strong, tendon, which is inserted into the mandible on its upper border, immediately in front of the articular end (Fig. 5, m'). The contraction of this part would draw the jaw against the quadrate, and, to a limited extent, close it. This last action, however, is powerfully effected by the united contraction of the temporals and masseters. Owen says : — " In the Cormorant, the osseous style, movably articulated to the superoccipital, affords to the temporal muscles a more extensive origin. This, indeed, is its essential use, for the muscles of the upper part of the neck are inserted into the occipital bone, and glide beneath the posterior or super-added fasciculi of the temporalis." 16. The biv enter maxilla, on either side, is that muscular mass which covers the mandibular articulation behind. It arises above from two points, viz: the ridge bounding the hinder part of the osseous ear, and secondly the depression to its mesial side. The two heads almost immediately blend as they pass downwards and forwards, as a curved fleshy mass, to become inserted into the posterior aspect of the articular end of the mandible, including the angle (Figs. 4 and 7). To study this muscle properly it should be transversely divided across its belly at about its middle ; the two extremities may THE MUSCLES OF THE HEAD. 19 then be easily dissected up,above, to its origin; below, to its insertion. The relations of this group, the openers and closers of the jaw, to the surrounding structures, as the ear, the dermo-temporalis muscle, and the quadrate, should be carefully examined. To expose the next set, divide the biventer maxillae as already directed, say on the right side ; cut the corre- sponding tendon of insertion of the temporal ; divide the masseter as its origin ; and finally disarticulate the man- biventer maxillcc rectus capitis posticus major FIG. 4. — Posterior view of skull of Raven. Life-size. Shows the origin of the muscles upon this aspect. After nature, by the writer. dible, lifting the cranium so that we have a plain view of its under side. Matters may be somewhat improved, too, by severing the zygoma at its middle, and pulling the extremities upwards. 17. The entotympanic is a small, spindle-shaped muscle, which arises quite fleshy from the side of the basisphenoid, and to a limited extent from the base of the rostrum immediately beyond it. As it passes backwards and downwards, it rapidly contracts to form c 2 20 THE MYOLOGY OF THE RAVEX. a double tendinous slip. One of these is inserted into a little spine-like process on the upper side of the shaft of the corresponding pterygoid, close to its quadratal articular end. The other is inserted into the quadrate itself, close to the pterygoidal articulation, and to its outer side. When these muscles contract, they pull forward the quadrates and pterygoids, which latter, in push- ing against the palatines, tend to raise the superior mandible. 18. The pterygoideus internus forms, with the aid of its fellow, the great muscular mass which is found at the roof of the mouth. It has a very extensive origin. On the upper side of the palatine the fibres arise over nearly the entire surface, at first fleshy, to become tendinous along the hinder margin of the bone. Similarly, on the inferior aspect they fill the fossa there found. As the fasciculi of this muscular mass pass backwards and out- wards, they are augmented by others, which find their origin upon the distal head and shaft of the corre- sponding pterygoid and the sphenoidal rostrum for some distance behind it. The fibres converge moder- ately, to make an extensive tendinous insertion upon the antero-internal aspect of the articular end of the mandible. Mesially, they are carried out to the ex- tremity of the inturned tip, wrhere the tendon is very strong ; while beyond they encroach slightly upon the ramus, where the insertion is more of a fleshy character (Figs. 5 and 6). 19. The pterygoideus externus is an exceedingly neat and well-defined muscle. It arises from the outer aspect of the extremity of the orbital process of the quadrate. The fibres form a roundish bundle, and slightly diverge as they pass forwards, downwards, and THE MUSCLES OF THE HEAD. 21 outwards, to insert themselves upon the inner aspect of the mandibular ram us, filling the fossa found in front of the articular enlargement, and in which we find the ramal vacuity. This latter foramen is closed in by the pterygoideus externus in this situation, while outwardly the masseter covers it up, the two muscles at this point being practically in contact. 20. The digastric arises on either side from an ellip- tical, longitudinal space, of no great size, situated at the base of the cranium, on the externo-lateral angle of the FIG. 5. — Left lateral aspect of mandible of Corvus corax sinuatus, slightly tipped forwards to show muscular attachment on inner sido. Life-size, m', the point of insertion of the zygornatic division of the masseter. basitemporal (see Figs. 7 and 11). From this origin the muscle passes down the side of the neck as a thin, narrow band of fibres. Opposite the angle of the jaw these begin to diverge, and spread out in a fan-like form, to meet a corresponding expansion of the opposite muscle in a median raphe, which extends longitudinally over the superior larynx. They are still more definitely inserted into the cartilaginous continuation of the second basitemporal about its sides. The middle portion of this extremely attenuated muscular stratum is very 22 THE MYOLOGY OF THE RAVEN. difficult to thoroughly trace in the younger specimens of Ravens, and it admits of our seeing the underly- ing structures through it. The delicate fibres of the platysma myoides overlie it, while its anterior fasciculi blend with those of the mylo-hyoideus. According to Mivart, in birds and reptiles the di- gastric descends from the hinder part of the cranium to the posterior end of the mandible, and in some birds is divided into three portions (Elem, Anat., p. 313). As we have just seen, it is still different in the Corvidce. The chief use of this muscle would seem to be to raise the hyoid apparatus and trachea against the pha- rynx, after a morsel of food has passed that point, to prevent its return to the mouth, and assist its passage down the oesophagus. III. THE MUSCLES OF THE TONGUE. IN this section I will speak of those muscles of the Raven which I have found upon dissection to be, in FIG. 6. — Under side of mandible of a Raven, designed to show the sites of muscular attachment ; life-size, from the author's dissections. some way or another, attached to the hyoidean apparatus, and involved in its movements. 24 THE MYOLOGY OF THE RAVEN. In Fig. 7, and other illustrations to this work, I have made careful drawings of these parts, and en- deavoured to present this group of muscles in such a manner as they can best be seen and studied. The following are presented for our examination : — 21. Mylo-hyoideus. 25. Sterno-hyoideus. 22. Stylo-hyoideus. 26. Depressor-glossus. 23. Genio-hyoideus. 27. Cerato-glossal. 24. Cerato-hyoideus. 21. The mylo-hyoideus1 (Figs. 5, 11, and 17). --This muscle arises on the inner side of the mandible, just above 1 Professor Hans Gadow sees two parts to the mylo-hyoideus in birds, his M. MYLO-HYOIDEUS ANTERIOR corresponding to my inylo- hyoideus, as shown by me in Fig. 11 of the present work (see Bronn's Klassen, vi. Band, pp. 304-307). To me, the M. MYLO-HYOIDEUS POSTERIOR of Gadow did not seem to be sufficiently evident in the Raven to merit a separate descrip- tion, and it is in no way so distinct a muscle as he figures it in Ehea darwini (I.e., Fig. 1, M.ELp., p. 306). Nevertheless, it has been variously considered by other ana- tomists, and Gadow offers us the following synonymy and remarks thereon :— " 103. 1. Grupe des M. MYLO-HYOIDEUS. 103A. M. MYLO-HYOIDEUS ANTERIOR. M. genio-hyoidean. Vicq d'Azyr, 1773, p. 585, No. 1. Mylo-hyoidean. Cuvier. Duvernoy, p. 5, No. 1. ,, Gervais et Alix, p. 19. Mylo hyoideus transversus. Tiedernann, § 90, No. 1. „ „ Nitzsch, p. 134, No. 2. Mylo-hyoideus obliquus. Kutorga, p. 20. Khomboideus juguli. "Wiedemann, p. 70. Querer Unterkiefermuskel oder vorderer, oberflachlicher Kiefer- Zungenbeinmuskel. Meckel, p. 409, No. 2. Mylo-glossus s. transrersus mandibutce. Gurlt, p. 14. Mylo-hyoideus. Schneider, p. 145 ; Gadow. ,, Watson, p. 136. " Dieser Muskel erscheint nach Abtragung der Haut zwischen den beiden Unterkieferiisten. Er entspringt von der Innenflache, oder THE MUSCLES OF THE TONGUE. 25 the lower border and the inturned edge of the horny sheath of the bill. The line of its origin occupies about auch voru Bande des TJnterkiefers mit ganz quer gerichteten Fasern, die sich in der Mittellinie mit denen der anderen Seite unter Bildung eines longitudiualen Schnenstreifens vereinigen. Ge- wohnlich hat der Muskel keme direkte Verbindung mit dem Zun- genbein." [This is followed by an account of its variations in a number of groups of birds.] " 103B. M. MYLO-HYOIDEUS POSTERIOR. Mylo-hyo'idien. Vicq d'Azyr. Serpi hyo'idien . C u vier. ,, Duvernoy. Retrahens linguce. Wiedernann, p. 71. Mylo-hyoideus obliquus. Tiedemann, § 90, No. 2. „ „ Kutorga, p. 20. „ „ Nitzsch, p. 135, No. 4. Heber des Zungenbeins. Meckel, p. 409, No. 1. Mylo-hyoideus. Gurlt, p. 14. Retractor de Vhyoide ou serpi-hyo'idien. Gervais et Alix, p. 18. Serpi-hyoideus + Stylo-hyoideus. Gadow, pp. 66, 67. Retractor linguce. Watson, p. 135. " Halswiirts vom M. mylo-hyoideus, ebenfalls subcutan gelegen zerfallt dieser, grosser Yerschiedenheiten zeigende Muskel, bisweilen in zwei Theile. Bei Rhea darwini entspringen beide zusammen von der AussenflJiche des hinteren Ende des Unterkiefers, laufen liber die nach Aussen ubergreifende Insertion des M. pterygoideus, werden breiter und theilen sich in eine vordere und eine hintere Masse. Die letztere (M. serpi-hyoideus) gebt mit ziemlich trans- versaler Bichtung zur Mittellinie ; ihre tieferen Zlige befestigen sich am Bindegewebe der Ventralfliiche des Larynx, die oberflachlichen vereinigen sich aponeurotisch mit denen der anderen Seite und strahlen zugleich auf den Hinterrand des M. mylo-Jtyoideus, sowie halwarts auf den M. constrictor colli aus. Die vordere Masse (M. stylo-hyoideus} ist schmaler, geht schrag vorwarts und einwiirts und inserirt sich in dem von den beiden Zungenbeinhornern und dem Zungenbeinkorper gebildeten Winkel ; der Insertionstheil wird ventral warts vom M. mylo-hyoideus anterior bedeckt." After giving its variations in a number of groups of birds he adds that " Bei Corvus kommt der gemeinsame Ursprungstheil 26 THE MYOLOGY OF THE RAVEN. the anterior third of the entire length of the ramus, and is carried forward to the posterior margin of the horny covering of the beak, where the latter overlaps the symphysis. Its wonderfully delicate fibres are di- rected transversely to meet those of the muscle coining from the opposite side. The two unite in a mid-longi- tudinal raphe, which as it is produced backwards be- comes faintly tendinous, and is finally inserted as an attenuated aponeurosis into the under side of the hyoid, between the first and second basi branchial, in the middle line (Fig. 17). The thin sheet of muscle thus formed spans and stretches completely around the forepart of the inter- ramal space, and by its contraction the tongue is lifted upwards against the roof of the mouth. This muscle is well developed in other classes of animals. Professor Mivart found it very large in Mcno- poma, and it varies considerably among the higher Mammalia, 22. The stylo-liyoideus is the name used by Professor Owen for a muscle which is quite conspicuous in the Kaven. Its origin and insertion are well shown in Fig. 7, where the lingual apparatus is drawn down by the dissecting chains, in order to put it on the stretch (see various views of the mandible, where it is shown). The stylo-hyoideus arises on the outer aspect of the articular enlargement of the mandible, at about the middle point. Its fibres form a rather long, transversely hauptsachlich von der ausserlich den M. liventer mandibulce bedeckenden Fascie." Having carefully dissected the mylo-hyoideus out in some fifteen specimens of the Raven, it seems but proper that I should say here that my observations upon it agree with those of Owen, and in the form, in question I have thus far failed to detect a posterior mylo- hyoideus (see Owen's Anat. Verts., vol. ii. p. 153). THE MUSCLES OF THE TONGUE. 27 flattened fasciculus, which proceeds downwards and forwards to be inserted by a delicate tendon into the head of the cerato-branchial of the thyro-hyal of the corresponding side on its upper aspect. When these muscles contract in unison, they tend to raise the tongue towards the palate, but if they act singly this member is pulled to the side towards which the contracting muscle is directing- it. We find that " in some birds it divides O into three or more portions : the posterior descends obliquely forward, and is inserted into the tendinous commissure of the mylo-hyoideus ; the middle portion is inserted into the urohyal [second basibranchialj ; the anterior fasciculus is inserted into the side of the basihyal above the transverse hyoglossus. The actions of these different portions vary according to their in- sertion ; the first and second depress the apex of the tongue by raising the urohyal, the third raises the tongue and draws it to one side when it acts singly " (Owen). 23. The genio-liyoideus is the largest and most powerful muscle of the group we are now examining (Figs. 5 and 7, and others). It arises from an extensive area (two in some birds) on the inner side of the mandible nearly as far forward as the horny part. The fibres unite to form a broad band, transversely compressed, which passes downwards and backwards until it meets the outer side of the corresponding thyro-hyal, about its middle ; this it envelops, by a spiral turn and a half, to its very extremity. It is quite evident that the contraction of this pair of muscles will have the effect of protruding the tongue from the mouth. 24. The cerato-liyoideus (Figs. 7 and 9). — I find the muscle so named by Owen to have a somewhat differ- ent insertion than that eminent anatomist gives it for fee 3 s J oj o .2 § « M - § J g ;SD THE MUSCLES OF THE TONGUE. 29 the class, generally. Of it, he says that " it passes from the thyrohyal to the urohyal, and is therefore sub- servient to the lateral movements of the tongue " (Anat. Verts., vol. ii. p. 154). This duty it also performs in the Raven, where we find it arising on the under side of the shaft of the epibranchial element of the thyro-hyal by a delicate tendinous slip. This soon becomes muscular as it passes forwards, forming a long slender belly, which is closely applied to the hyoid. Opposite the first basibranchial it is again a long tendinous slip, and thus remains until it is finally inserted into a little bony elevation on the under side of the anterior end of the corresponding cerato-hyal. Owing to the free lateral movements enjoyed by the joint at the anterior end of the first basibranchial, it is quite clear that either of these muscles acting singly must pull the tongue to one side. But the joint referred to also operates in the opposite direction, so that, united action of the pair would tend to depress the tongue. 25. The sterno-liyoideus (Figs. 9 and 17). — Agreeing with the majority of birds, we find in the Raven either sterno-hyoideus arising from the anterior surface of the thyroid bone of the superior larynx. The muscular fibres at the origin are quite fleshy, but as they converge and pass forwards, they become rather more tendinous, and are thus constituted as they are inserted into either cerato-hyal at its base. Other fibres, which hold a more mesial position, unite with the corresponding ones of the muscle of the opposite side, to pass into and finally be lost in the tissue composing the soft part of the tongue, at its base. These latter are not well shown in Fig. 17, as they are huddled together by the traction of the little dissecting hook and chain, which pulls the muscle to one side so that the depressor glossus may be seen. 30 THE MYOLOGY OF THE RAVEN. If these muscles contract in unison, the larynx being the fixed point, they will evidently depress the tongue. Acting singly in the same way, either one will likewise depress the tongue, but also give it a lateral deflection to the side towards the muscle which is contracting. If they contract together, with the base of the tongue as the fixed point, they will pull the larynx forwards, a very necessary movement during the accomplishment of the act of deglutition. 26. The depressor-glossus is the name 1 have bestowed upon a small but important muscle which Professor Owen describes in the following words : "A small and short muscle, which is single or azygos ; it passes from the basihyal to the under part of the glossohyal ; it depresses the tip of the tongue and elevates its base" (loc. cit., p. 154). Nameless though he left it, Professor Owen's description answers very well indeed for a corresponding muscle that wTe find in the Raven, and the one, as I say, I propose to call the depressor -glossus. In this bird it arises fleshy over the entire under surface of the first basibranchial (basihyal of Owen), the fibres contract as they pass forwards, and become tendinous between the tongue bones, and as a delicate tendon so continue on to finally find an insertion at their tips, where they meet anteriorly (Fig. 17). When this muscle contracts, the tongue must behave in a manner already described, and quoted from the authority above. 27. The cerato- glossus is a small muscle we find on the upper side of the hyoid, one on either cornua. Each occupies, as an origin, the half of the surface of the first basibranchial. After passing over the joint formed by the head of the thyro-hyal, the fibres become more tendinous, as they insert themselves along the upper side of the shaft of the cerato-branchial element. They Tiff. 20 FlG. 8. — Oblique view from the inner side of the furcula, coraeoid, and scapula of the Raven, showing the areas devoted to the muscles which take origin from these bones. Life-size. FlG. 9. — Under view of the hyoid arches of a Raven, with the upper part of the windpipe, in situ. Designed to show the origin and insertion of certain muscles of the tongue, m.h., lingual attachment of the mylo-hyoldeus. Life-size. FlG. 10.— Superior view of the bones of the upper larynx and half-rings and rings of the trachea. Shows the origin and insertion of the two muscles which control the rima glottidis. x 2. All the figures drawn by the author from his own dissections. 32 THE MYOLOGY OF THE RAVEN. FIG. 11. — Under view of the head of a Haven, with mandible in situ, but with hyoid apparatus and other parts carefully removed. Dissected to show the muscles which occur upon this aspect ; the left side (the right in the figure) shows the origin and insertion of the ptcrygoideus internus. The opposite side is dissected to show the entotympanicus and pf.ery- goideus cxternus. The anterior two-thirds of the mi/lo-hyoideus is also shown, and its mode of attachment. The digastric is cut off close at its point of origin. This figure should be carefully compared with Fig. 3 of the present memoir. Life-size, by the author from his own dissections. here glide beneath the thyroid bone of the superior larynx. Just beyond this point they become fully THE MUSCLES OF THE TONGUE. 33 tendinous, and are finally inserted as a distinct tendon at the muscle's termination on the shaft of the element just alluded to, and in line with the last-named fibres. According to Professor Owen, Dr. Salter proposed the name of this muscle which I have here adopted for it. The former anatomist describes it as " a short muscle, which arises from the junction of the basihyal with the urohyal, and is inserted into the thyrohyal ' (loc. cit., p. 154). Professor Owen figures it in a Fieldfare, but makes an incorrect reference to his figure, and the muscle is shown, apparently, as being pulled out of its normal position, in order to show the stylo-hyoideus. When these muscles contract, they will elevate the long cornua of the hyoid arches, and press them up against the skull. In addition to the muscles already described as be- longing to the tongue, there is still another pair, found by Owen in a Woodpecker (shown in Fig. 12 at h), which he has named the cerato-tracheales, and says : " They arise from the trachea about eight lines from the upper larynx, twist four times spirally round the trachea, and then pass forward to be inserted into the base of the thyro-hyals. This is the principal retractor of the singular tongue in this species ' (Anat. Verts., vol. ii., p. 154). Unfortunately, Professor Owen does not mention in his work the species of Woodpecker in which he found this interesting pair of muscles. He speaks of it, however, in such a way as to lead one to suppose that it occurs throughout the family. Dissections made upon our American forms, with a view of looking further into this matter, would be well worth the time and labour of the comparative anatomist. D 34 THE MYOLOGY OF THE RAVEN. Referring again to Professor Gadow's estimable work in Bronn's Klassen des Thier-Reichs (vi. Band, pp. 307-317), we find that he has described and proposed the following nomenclature for the muscles of the lingual ~ o apparatus in birds. In presenting this I refer to the plates of this writer, although his figures are not here reproduced. It will be observed that he has bestowed very different names upon the muscles as compared with Owen's nomenclature, the authority at my hand when the present volume was written. " II. Muskeln des Zvmgengeriistes. (Taf. xxxii., xxxiii., und Holzschnitte.) " 104. SYSTEM DES M. STERNO-HYOIDEUS. Thyreo-hyoideus. Vicq d'Azyr ; Gervais et Alix, p. 18. M. laryngo-hyo'idei. Tiedemann, § 90, No. 5. Hyo-thyreoideus. Kutorga, p. 20. Gurlt, p. 15. Thyreo-hyoideus. Nitzsch, p. 136, No. 5. Thyreo-glossus. Nitzsch. Thyro-hyoid. Watson, p. 136. M. ypsilo-trachealis s. dejrressor arterice asperce superficialis, major. Meckel, 6 Theil, p. 284. Sterno-hyoideus. Nitzsch ; Gurlt, p. 15. Tracheo-sternalis. Gadow, Tenuirostres, p. 68. Omo thyreoidei. Huber. Les cerato trachees. Cuvier. Cerato-trachei. Tiedemann, p. 122. Tracheo-glossi. Huber. Cerato-trachealis. Owen. Traclieo-liyo'idien. Duvernoy. Tracheo-hyoideus. Gadow, p. 62. " Bin echter, an das bei den Eeptilien allgemeine urgpriingliche Verhalten anschliessender M. sterno-hyoideus ist noch bei Apteryx vorhanden. Der breite Muskel entspringt vom vorderen Rande der Unterfltiche des Thyreoid-Knorpels des oberen Kehlkopfes und vom ganzen Innenrande der Zungenbeinhorner. Seine Fasern sind abwiirts gerichtet, verbinden sich theilwoise mit denen der anderen THE MUSCLES OF THE TONGUE. 35 Seite in der ventralen Mittellinie und bilden dann eine ziemlich dicke und breite Muskellage, welche veutral und seitlich die Trachea lose umgiebt, ohne jedoch an derselben befestigt zu sein. Nahe der Brust angelangt, theilt .sich die bis dahin vereinigte Masse in eine rechte und eine linke Hiilfte, deren jede sich am ganzen Seitenrande des Sternums und auch am grossten Theile des hinteren oder caudalen Randes des Brustbeines inserirt. Die Brust- und Schultermuskeln werden natiirlich von den theilvveise aponeuro- tisch gewordenen, flachen Insertionstheilen des M. sterno-Jiyoideus bedeckt. " Der Muskel wird durch Zweige des N. hypoglossus, und weiter abwarts von den meisten Cervicalnerven aus innervirt. " Als eine mediane, innere, von dem eben beschriebenen Muskel abgetrennte Masse ist ein Muskel aufzufassen der bei Apteryx mit geringer Ausdehnung fleischig vom Coracoid, nahe dessen Verbin- dung mit dem Sternum entspringt uiid sich streng median- und kopfwarts gerichtet, etwas oberhalb der Theilung der Trachea in die Bronchien an der Trachea befestigt ; von dort begleitet er die Trachea, an derselben seitlich besfestigt, wird im Bereich des oberen Drittels der Luftrohre sehr schwach, schwillt aber nahe dem Thyreoidknorpel wieder an und inserirt sich an dessen Seiten- und Unterflache. Wir bezeichnen ihn als M. sterna s. coraco-thyreoideus. Dieser Muskel wird ausschliesslich durch einen Ast des N. hypoglossus innervirt, der bis in die Brust hinabsteigend in dem Muskel verfolgbar ist. " Andere das Sternum und den Schultergiirtel mit der Trachea oder mit dem Zungengeriist verbindende Muskeln besitzt Apteryx nicht. Das bei diesen Ratiten bestehende "Verhiiltmss giebt uns Aufschluss iiber die complicirteren Zustiinde bei den andern Vogeln. Aus den beiden Muskeln des Apteryx sind mehrere entstanden, von denen aber nur die mit dem Zungengeriist in Verbindung stehenden hier besprochen werden, wahrend die iibrigen, als in den Dienst der Respiration und Stimrnbildung getreten, bei jenen Organen er- schopfend behandelt werden. Ein M. sterno-hyoideus findet sich ausser bei Apteryx bei manchen Carinateii. Bei Prosthemadera wird er jederseits durch ein schmales Band gebildet, welches im Winkel der Symphyse der Furcula entspringt und direkt, ohne andre Verbindungen einzugehen sich an der Basis des Zungenbeins und zwar mehr an dessen Dorsalseitenrand inserirt ; nur wenige Fasern befestigen sich an der Wurzel der ZungenhiJrner. " Bei Meleagris ist nur die bei Apteryx als innere erwiihnte mediane D 2 36 THE MYOLOGY OF THE RAVEN. Portion vorhanden. Dieselbe kommt vom Proc. lateralis anterior des Brustbeins, geht zur Seite der Trachea, wird sehr schwach und schwillt am obern Ende wieder an, um sich am Larynx und am Os urohyale zu befestigen ; ausserdem aber ist sie nahe dem Larynx an jeden der Trachealringe befestigt, oder eigentlich kommt von diesen Ringen und geht zum Urohyal, den benachbarten Theilen des Basihyal und der Zungenhorner, Als eine dentliche Abspaltung des angen Muskels besitzt Meleagris noch einen, der sioh vom ventralen und seitlichen Eande des Thyreoidknorpels und vom Seitenrande des ersten Trachealringes selbstandig und frei an der Seite des Halses her abzieht, in der Nahe der Schulter aber ventral warts mit dem der anderen Seite convergirt und eine sehr diinne, ziemlich schliipfrige Schicht von Bindegewebe ohne Muskelfasern bildet, die sich allmalich an der Ventralflache des untern Endes der Luftrohre anheftet. Diese beiden langen Muskeln von Meleagris werden von einem Zweige den N. hypoglossus begleitet. " Denkt man sich nun, wie das iibrigens schon bei Apteryx und Meleagris angedeutet ist, dass die Fasern des M. sterna hyoideus und claviculo-hyoideus im Bereich des mittleren Halsdrittels verklim- mern, so zeri'allen ebengenannte Muskeln je in einen obern Theil, der dann als tracheo-hyoideus und tracheo-laryngeus superior und in einen untern Theil, der als sterno- s. coraco- s. clddo-trachealis und tracheo-laryngeus inferior betrieben werden kann. Jeder derselben kann wieder in Unterabtheilungen zerfallen. " So haben wir bei Rhea folgende Muskeln : 1. Ein M. tracheo- aryngeus superior. Derselbe erstreckt sich von der Ventralflache des Hinterrandes des Thyreoids auf die Seitenfl-ache des obern Drittels der Trachea. 2. Sein vorderster Theil ist ein Thyreo-glossus s. hyoideus, denn er verbindet die Ventralflache des Thyreoids mit dem Hinterrande des Os basihyale. 3. Von der Seitenmuskulatur der Trachea lost sich ein wohlentwickelter bandartiger Muskel ab, der sich am obern Ende des ersten Gliedes des Zungenbeinhornes befestigt, daher M. tracheo-hyoideus zu nennen ist. 4. Die Brust- partie derselben Muskelmasse ist sehr diinn geworden und verliert eich in der Haut des Halses, ohne mehr die Brust zu erreichen. Ausserdem ist 5, ein Sterno-trachealis vorhanden und ein daraus differeuzirtes Paar Syrinx-Muskeln. "Bei Nycticorax griseus besteht ein clem M. tracJieo hyoideus und thyreo-hyoideus von Rhea vergleichbares Muskelpaar, das mit einigen Ziigen von der Trachea, hauptsachlich aber vom Thyreoid- Knorpel zum Basihyal geht. Die Luftrohre wird nicht von Mus- THE MUSCLES OF THE TONGUE. 37 keln begleitet, die betreffeiiden Theile sind dalier ausgefallen, und nur ein M. sterno-trachealis nebst einem priniitiven Syrinxmuskel oder M. tracheo-bronckialis ist vorhanden. " Bei Cacatua roseicapillus kommt ein dilnnes Muskelband vorn Larynx und voui Zungengeriist ; ein Theil begleitet die Luftrohre bis zu den Syrinx- und Tracheo-clavicular-Muskeln und wird wie diese nur vom N. hypoglossus innervirt ; ein dickerer, mehr seitlicher Theil breitet sicli bald auf der Halshaut aus, verwebt sich dort mit den Hautrnuskeln und erreicht das Brustbein. oder den Schulter- giirtel nicht. Hauptsachlich von einem langen Zweige des N. hypoglossus versorgt, erbalt er weiter unten auch Zweige aus den Cervicalnerven. " Beim Griinspecht (Taf. xxxiii., Fig. 35A) [not here reproduced], konimt jederseits ein diinner Muskel vom Schultergiirtel, begleitet die Trachea in ihrer ganzen Lange und stbsst erst nahe dem Kehl- kopfe mit dem der anderen Seite zusainmen, worauf sich beide am Thyreoicl und dem medianen Zungengeriist iiiseriren. — Ein zweiter Muskel kommt von der Clavicula und geht etwas seitlich von dem vorigen gerade kopfwarts als ebenfalls schmales Band und inserirt sich am Thyreoidknorpel und am Grunde des Zungenbeinhornes seiner Seite. " Ein dem M. tracheo-hyoideus entsprechender Muskel erreicht bei den Spechten seine hochste Entwicklung. Er entspringt jederseits von der Trachea unterhalb des Kehlkopfes, windet sich dann mehrere Male (beim Griinspecht viermal) lose um die Luftrohre und geht dann an die Basis des Zungenbeinhornes. Bei weit herausgestreckter Zunge entrollt sich dieser eigenthiimliche Muskel seine Funktien ist Zurriickziehen der Zunge. " Wir koiinen dalier diejenigen Zungenmuskeln, welche entweder mit dem Brustbein und Schultergiirtel, oder mit der Luftrohre und dem oberen Kehlkopfe zusammenhangen, folgendermassen zusammeri- fassen. " I. Gruppe. " Vom Sternum zurn ganzen Zungenhorn, und zum Basihyal : Sterno-hyoideus ; Apteryx. " Von der Clavicula hauptsiichlich zum Zungenkorper ; Cleido- hyoidei ; Prosthemadera, Ptilotis, Pici. " Dieselben Muskeln erreichen aber die Brust nicht, sondern sind an der Halshaut befestigt ; Papageien. "II. Gruppe. " Von der Trachea znni Zungengeriist und z\var zum Cerato-hyal ; 38 THE MYOLOGY OF THE RAVEN. Tracheo-hyoidei ; Nectarinia ; Pici ; Grallse ; Rasores ; Eaptores : Rhea. " Vom Larynx (Thyreoid) und theilweise auch von der Trachea zum Basihyal, Entoglossum und Urohyal ; Thyreo-hyoidei ; Anser ; Callus: Rasores; Ptilotis ; Rhea; Spheniscidse. " 105. M. GENIO-HYOIDEUS. M. genio-hyoides. Steno. Le muscle conique de I'os hyoide. Vicq de Azyr, 1773, p. 535. Protahens linguce. Wiedemann, p. 71. Mm. conici ossis hyoidei. Tiedemann, § 90, No. 3. „ „ Kutorga, p. 20. Tiefer Vorwiirtzieher oder Kinnzungenbeinmuskel. Meckel, p. 409, No. 3. Mylo-cerato-hyoidien. Duvernoy. Genio-hyoideus. Gurlt, p. 15. „ Nitzsch, p. 135, No. 3. ,, Gadow, Tenuirostres, Proc. Zool. Soc., 1883, p, 67- Mylo-ceratoideus anterior et posterior. Nitzscb, in seiner Tafeler- kldrung, p. 151. Genio-ceratoideus. Huber. Protracteur de I'hyoide (genio-ltyo'idieAi). Gervais et Alix, p. 18, Protractor linguce. Watson, p. 135. " Dieser Muskel entspringt vom inneren, unteren oder vom oberen Rande des Unterkieferastes, ungefiihr in dessen Mitte und geht bandformig gerade nach hinten, ventral von clem M. mylo-hyoideus anterior, aber dorsal oder in derTiefe von M. mylo-hyoideus posterior gelegen, an die vorwartsschauende Seite der Zungenbeinhorner, um die er sich theilweise herumwindet ; ihr Enddrittel ist ganz von den Muskelfasern umgeben. So verhalt es sich bei vielen Vogeln, z.B. bei Corvus, Anser, Procellaria, Spheniscus. Hiiufig jedoch (Nec- tarinia, Otis) zerfallt das vom Unterkieferkommende Band in zwei, von denen das eine sich wie gewohnlich um das Zungenbeinhorn herumwickelt, wahrend das andere sich nur an der ausserten Spitze desselben befestigt, beide Theile sind aber von einer gemeinsamen schliipfrigen Scheide umgeben, wodurch ihr Zusammenwirken und zwar ausschliesslich in der Richtung des Knochens, gesichert ist. Bei Prost/temadera war der Ursprung des Bandes auf die Aussen- flache des Unterkiefers geriickt. " Bei den Papageien ist der Muskel ganz getheilt. Der vordere (Taf. xxxii., Fig. 30o) [not re-figured here] entspringt vorn an der THE MUSCLES OF THE TONGUE. 39 inneren Flache des Unterkiefers und geht zum letzten Drittel des ersten langen Gliedes des Zungenbeinhorns, erstreckt sich auch wohl etwas zum zweiten, umwickelt aber bei Papageien das Zungenbein- horn nickt so wie bei vielen andern Vbgeln. Der hintere Theil (Fig. 30c) [not re-figured here] entspringt weit vom vorderen ent- fernt am unteren Eande des Unterkieferastes etwa in der Mitte seiner Lange und geht an das sehr kurze zweite Glied des Zungen- beinhornes seiner Seite. Nitzsch schlagt flir diese beiden Muskel- theile die Namen M. mylo-ceratoideus anterior und posterior vor. Bei Rkea sind ebenfalls zwei ganz getrennte Bander vorhanden. Das vordere entspringt aus dem Kinnwinkel und stb'ssfc in der Mit- tellinie mit dem der anderen Seite zusammen ; es inserirt sich am Ende des ersten Gleides des Zungenbeinhornes. Das aussere Band ist schmaler und wickelt sich urn die iiusserste Hiilfte des letzten Gliedes des Zungenbeinhornes. " 106. M. GENIO-GLOSSUS. M. myloglosse. Duvernoy, p. 6, No. 5. M. genioglossus. Nitzsch. " Dieses Muskelpaar scheinen nur wenige Vogel zu besitzen. Bei den Papageien entspringt es vorn dicht neben der Mittellinie der inneren Kinnfliiche, wird vom M. mylo-hyoideus bedeckt und begibt sich als diinnes Band an den Seitenrand des hinteren Endes des Os entoglossum. Nach Nitzsch fehlt es bei vielen anderen Vogeln, oder es ist, wie bei den Raubvbgeln, wo es im Frenulum der Zunge vom Rachen aus durchscheint, so schwach, dass es leicht iibersehen wird. " Den Penguinen, Trappen, Gansen, Kriihen, Hiihnern, Spechten Kolibris, Nectaritiien scheint es in der That zu fehlen. " Bei Procellaria ist der Muskel sehr dlinn, liegt der Mundschleim- heit an, und erstreckt sich vom seitlichen hinteren Theile des Os entoglossum diinner werdend und mit dem der andern seite con- vergirend zum Kinn." • • • • • " 107. M. CERATO-GLOSSUS. Cerato-c/losse. Cuvier. Cerato-ylosse. Duvernoy. Cerato-gfossus. Tiedemann, § 91, No. 1. ,, Kutorga, p. 21. 40 THE MYOLOGY OF THE RAVEN. Ceralo-ylossris. Watson, p. 134. „ Gadow, p. 67. Nieder- und Seitwartszieher der Zunge. Meckel, p. 408, No. 1. Ceratoglossus inferior s. basioglossus lateralis und superior. Nitzsch, p. 136, 137. Basioylossi inferiores et superiores. Kutorga, p. '21. L'hyo-glosse. Gervais et Alix, p. 18. Grund-Zungenmuskel (basio-glossus). Gurlt, p. 15. Griffel- oder Zangenbein-Zungenrauskel (stylo-Jiyoideus). Gurlt, p. 15. " Im allgemeinen entspringt dieser stets vorhandene Muskel fleischig von der oberen Flache des ersten Abschnittes des Zungen- beinhornes und inserirt sich mit einer langen, deutlichen Sehne am Seitenrande des Os entoglossum. Haufig zerfallt er in zwei Tbeile ; der eine kiirzere geht bei den Hiihnern vom Zungenkorper (Os en- toglossum) bis fast zur Spitze der Zunge, die er herabkriimmt, er liegt dann auf der Ventralseite der Zunge ; der andere langere kommt vom Zungenbeinhorn und endigt sehnig am Grunde des Korpers." [This account of the cerato-glossus (the cerato-glossal as described by me above for the Haven) is completed by Gadow by a few words upon its variations as found by him in a number of groups of birds.] " 108. M. CEEATO-HYOIDEUS. Cerato-hyo'idien. Cuvier. Cerato-hyoideus. Tiedemann, § 90, No. 4. ,, Kutorga, p. 21. Meckel, p. 409, No. 4. „ Nitzsch ; Gurlt, p. 14. ,, Duvei-noy. Ceratoidien transverse. Gervais et Alix, p. 19. Gerato-lransverse muscle. Watson, p. 134. " Ein kurzer Muskel, der fleischig von der Innenseite des ersten Stiick.es des Zunge nhoriies eutspringt und mit schriig vorwarts und median gerichtetem Verlauf an den unpaarigen Stiel des Zungen- geriistes (Os urohyale) inserirt, haufig verbinden sich dabei die gegenseitigen Muskelziige. " Verwebung mit dem ventral gelegenen M. mylo-liyo'ideus pos- terior ist gewohnlich.- — Fehlt aus Os urohyale, wie bei lihea und bei Flatalea, so ist auch der Muskel nicht vorhanden, letzteres gilt aber THE MUSCLES OF THE TONGUE. 41 auch bei vielen Vogeln, welche wie der Flamingo, Storch, maiiche Eaubvogel, Prosthemadera, Nectarinia den unpaarigen Stiel be- sitzen. " Bei Eudyptes chrysocome ist der Muskel reclit lang ; er kommt vom zweiten Drittel des Zungenbeinhornes nnd verbindet sich auf dem Urohyal mit dem mylo-hyoideus. Er scheint eine den Vogeln eigenthiirn-Differenzirung des M. cerato-glossus zu sein. " 109. M. HYPOGLOSSUS. " Jederseits aus einem oder zvvei Muskelchen bestebend, die von der Uuterflache des Os basibyale entspringen und neben einander auf der Unter- und Seitenfliiche des Os entoglossum sich inseriren. Sie werden durch eineu Zweig des Ramus lingualis N. hypoglossi innervirt und sind hb'chstwahrscheinlich als tiefere, etwas selbstandi