592 



AMERICAN MUSEUM OP NATURAL HISTORY 



Skull — Cont'd. 



1911.1; Voskoboinikov, M. M. 1910.1; 



•Winslow, G. M. 1898.1. 



Those treating especially of the origin 

 of the membrane bones (Deckknochen) . 

 Gaupp, E. 1903.1; Goeldi, E. A. 1884.1; 

 and Walther, J. K. 1883.1. 



Other papers treating both of the develop- 

 ment of the chondrocranium and the bony 

 skull of the Teleosts in general, and especially 

 ofSalmo. •Boker, H. 1913.1; •Klein, 

 A. 1884.1; Parker, W. K. 1872.1; Pou- 

 chet, G. 1874.1; •RosSn, N. 1910.1; 

 •Sohleip, W. 1903.1; •Swinnerton, H. 

 H. iGasterosteus) 1902.1; Tikhomirov, 

 A. A. 1885.1; Vrolik, A. J. 1873.1; 

 Waicox, M. A. 1899.1; Ganin, M. Add. 

 1880.1. 



MORPHOLOGICAL TOPICS 



Concerning the skull 



There is an extensive literature on the skull 

 concerning the determination of the homologies 

 of the various cranial and skull elements through- 

 out the vertebrate and especially the Tetrapod 

 series. This literature is obviously beyond the 

 sphere of the present work. 



Orbitosphenoid, structure. Starks, E. C. 

 1908.3. — Sphenotic. Baraldi, G. Add. 

 1883.1. 



Morphology of the palatoquadrate in — 

 Selachii. Allis, E. P. Wli.l. — Dipnoi. 

 •Boas, J. E. Add. 1914.1. 



Fontanelles 



In some fishes, certain skull bones such as 

 the frontals and parietals fail to coalesce in the 

 median line leaving open median pits or fon- 

 tanelles. 



These are fully discussed, in the skull of 

 Placoderms and Siluridoe, by •Dean, B. 

 1891.2. This paper is reviewed by Wood- 

 ward, A. S. 1891.9. — Conditions in 

 Callichthys. Klinckowstrom, A. 1893.2. 



The Jaws 



Lesser papers on the homologies of the 

 jaw elements throughout the vertebrate 

 series. Albrecht, P. 1883.1, 1884.1; 

 Bardeleben, K. 1905.1-1907.1; Broom, 

 R. 1913.4; Humphry, G. M.- 1865.1; 

 Jourdain, S. 1878.1. 



The sesamoid articular, a bone present in 

 the mandible of some fishes. •Starks, E. 

 C. 1916.1; Storrow, B. 1910.2. 



Minor papers descriptive of the jaws in 

 the following forms. — Amia and Hydro- 

 cyon. Brilhl, C. B. 1891.1. — Cyprinus. 

 Freund, L. 1909.2. — Esox and Teuthis. 

 Hilgendorf, F. M. 1872.1, 1880.1. — Hem- 

 iramphus. Hopewell-Smith, A. 1908.1. 

 — Gadus. •Petersen, H. 1914.1. 



For figures of the jaws of various sharks 

 and rays, see Garman, S. 1913.1, and 

 Radoliffe; L. 1916.1. 



Latero-sensory Canals 

 The latero-sensory canals of fishes, traversing 

 certain cranial bones, are remarkably constant 

 in position, and give important and often posi- 

 tive evidence as to the homologies of these bones. 

 It is generally accepted that certain bones de- 

 velop in direct relation to these canals. The en- 



closure of the canals takes place in two distinct 

 manners, called by Allis, plagiostomian and 

 teleostean. 



These matters, with the literature, are 

 fully discussed in •Allis, E. P. 1904.1. 



An old paper on this subject is Stannius, 

 F. H. 1842.3. 



Morphology of the Myodome 



The myodome of fishes, according to Allis, ia 

 primarily a sub-pituitary space connected with 

 the orbit of either side or the orbital region by a 

 canal which transmits the pituitary vein. This 

 space secondarily acquired a wide communica- 

 tion with the orbits apparently by the enlarge- 

 ment of the eyeballs which caused a deepening 

 of the orbits followed by the entry of certain 

 eye-muscles into the pituitary canal and the 

 final complete destruction by them of the wall 

 separating the orbits from the subpituitary 

 space. The myodome of Amia is believed to be 

 strictly homologous (p. 193) with the cavernous 

 and intercavernous sinuses and the Cava Meck- 

 elii, together, of the human skull. 



This topic is comprehensively treated, 

 with a full review of the literature, by •Allis, 

 E. P. 1909.1, pp. 183-203. See also 

 Starks, E. C. 1905.2. 



The Operculum 



Much interest seems to have been exhibited, 

 a century or more ago, in the morphological 

 significance of the operculum. The following 

 references, although not seen by us, seem to 

 have little other than historical value. 



Blainville, H. M. 1817.1, .2; Bojanus, 

 L. 1817.1; Eiohwald, C. E. 1833.1; 

 Geoffroy-St. H., E. F. 1817.1, .2; Hollard, 

 H. L. 1863.1, 1864.1; Lavocat, A. 1888.1; 

 Oken, L. 1823.2. — Operculum in As- 

 predinidce. Eigenmann, G. H. 1892.8. 



Suspensorium of Jaws ■ 

 To express the manner in which the first 

 visceral or mandibular arch is connected with 

 the skull, Hujdey (T. H. 1876.1, p. 40) sug- 

 gested the terms autostylic where the man^- 

 bular arch is " attached directly to the skull 

 by ... its own substance; " hyostylic where 

 the hyomandibular " becomes the chief appa- 

 ratus of _ suspension; " and amphistylic for the 

 " condition of the cranium which tends to con- 

 nect the two [above] by a middle form." 



Subsequent research has necessitated fur- 

 ther precision in definition, which has been 

 supplied, with additional terms, by •Greg- 

 ory, W. K. 1904.2. 



Other papers relating to the suspenso- 

 rium. Carter, J. T. 1905.1; Gadow, 

 H. 1888.1; Huxley, T. H. 1859.1; Kerr, 

 J. G. 1908.2; Pollard, H. B. 1895.2; and 

 Swinnerton, H. H. 1902.1 (p. 568). 



SKULL BY GROUPS 



For the complete literature reference 

 should be made also to " Skeleton " and 

 to " Visceral skeleton." 



Cyclostomata 



The skull of this group consists entirely of 

 the chondrocranium. It is highly specialized 

 and its parts can not readily be homologized 

 with those of the skull of other vertebrates. 



Structure of the skull of Bdellostoma, 

 Petromyzon, and Myxine. •Allis, E. P. 

 1903.2; Neumayer,L. 1898.1; •Schaffer, 

 J. {Myxine) 1901.2; Schalk, A. 1913.1. 



