^{page 749 note *} The following works relate to the skeleton generally, those dealing with special points being referred to at the appropriate places:—A. A. Retzius, Kgl. Vet. Akad. Stockholm, 1824; J. Müller, Abh. K. Akad. Wiss. Berlin, 1834; P. Fürbringer, Jena. Zeits., ix., 1875; W. K. Parker, Phil. Trans., 1883; G. B. Howes, Trans. Liv. Biol. Soc., vi., 1892; Neumayer, Munchen. med. Abhand. (Kupffer and Rüdinger), Hft, 74, 1898; Ayers and Jackson, Jour. Morph., xvii., 1901, and Bull. Cincinnati Univ., vol. i., 1900; Allis, Anat. Anz., xxiii., 1903.

^{page 750 note *} For example, the structures named by Ayers and Jackson “branchial arches” are, according to Bashford Dean, developed after the gill pouches have disappeared from this region, and may therefore represent neomorphs developed in connection with the muscles of the “tongue.” In fact, I am disposed to believe that much of the Myxinoid skeleton is recent and sesamoidal (as indicated by Pollard), and therefore has no morphology at all!

^{page 751 note *} Jena. Zeits., vi., 1871.

^{page 751 note †} Arch. Anat. Phys., Anat. Abt., 1881.

^{page 751 note ‡} Z. f. w. Z., 62, 1896 (complete paper).

^{page 754 note *} i.e. in Bdellostoma. In his concluding remark (p. 340) he wrongly excludes Myxine.

^{page 755 note *} 1894, p. 349; and 1895, p. 415.

^{page 755 note †} Z. f. w. Z., 61, 1896, p. 606. A. f. m. A., 50, 1897, p. 170.

^{page 755 note ‡} Schaffer's term for the non-protoplasmic portion of the cartilage.

^{page 756 note *} A.f. m. A., 48, 1896, p. (506. Also 51, 1898, p. 452.

^{page 756 note †} This is surely a slip of the pen. The muscle should be the M. copulo-copularis, P. Fürbringer (M. constrictor musculi mandibuli, Ayers and Jackson).

^{page 756 note ‡} Sitz. K. Akad. Wien, Abt. iii., 105, 1896, p. 21.

^{page 757 note *} A term applied in 1878 to similar tissue in the frog by Stadelmann. I adopt it in preference to Schaffer's more cumbrous “vesicular supporting tissue.”

^{page 758 note *} Cp. the description of these two cartilages, and especially of the superior chondroidal bar.

^{page 760 note *} See his concluding remark, p. 340.

^{page 760 note †} Since writing the above, examination of further series of sections, especially of a vertical-longitudinal series, indicates that fusion does take place ventrally between the cartilage of the notochord and that of the parachordals. In fact, I now question whether the so-called anteriorly projecting tip of the chorda is not after all a part ot the parachordals. But these questions are difficult to settle with adult material.

^{page 760 note ‡} Das Gehörorgan d. Wirbelthiere, i., 1881.

^{page 761 note *} All the fenestrce are closed by fibrous membranes or tissue.

^{page 761 note †} This measurement is obviously erroneous.

^{page 763 note *} In two museum preparations made by Fric of Prag, it was present in one and not in the other.

^{page 766 note *} Op. cit., p. 386.

^{page 766 note †} Op. cit., p. 199.

^{page 767 note *} In one series of sections the fourth ring was not included on one side.

^{page 767 note †} Op. cit., p. 109.

^{page 768 note *} Op. cit., p. 3 and fig. 4. Apparently also by Pollard (p. 396).

^{page 768 note †} Anat. Anc., xxiii., pp. 269–270.

^{page 769 note *} Anat. Anz., viii., 1893, p. 59.

^{page 769 note †} Zool. Jahrb., Abt. Morph., viii.; Taf. xxv., fig. 11, 1895.

^{page 769 note ‡} Cp. the description of the latter cartilage.

^{page 770 note *} I have no actual record of the size of this specimen, but it would be about 10 cm. I have already referred to it as the 10 cm. Hag.

^{page 770 note †} Anat. Anz., ix., p. 351; and Zool. Jahrb., Anat. Abt, viii.

^{page 774 note *} This agrees with J. Müller's figure and description. Nevertheless I doubt it.

^{page 775 note *} This is the “median dorsal bar” of Ayers and Jackson. It is, of course, ventral.

^{page 776 note *} Parker gives for Myxiue 7 and 9, and J. Müller 8 and 8–9, which illustrates my point below.

^{page 780 note *} P. Z. S., 1892, p. 706.

^{page 780 note †} Bergens Museum Aarbog, 1898, No. 1, p. 6.

^{page 782 note *} It is, perhaps, rather a refinement of description to associate any part of the branchial skeleton with individual gill ducts, since, apart from the ductus esophago-cutaneus portion, its function on both sides and in all cases is to strengthen the wall of the branchial cloaca, and it is possible that all the gill ducts have contributed to it.

^{page 784 note *} Op. cit., p. 91.

^{page 784 note †} Fourth Ann. Rep. Fish. Bd., Scotland, 1885. Also Rep Brit. Assoc., 1885.

^{page 784 note ‡} For the complete paper, see Binl. Unters., vii., 1895, p. 26.

^{page 785 note *} In Bdellostoma, according to Ayers and Jackson, the spinal cord is not dilated.