^{page 345 note 1} Labelled “Stromalopora concentrica, Goldf., Culm, Bicken bei Herborn, Nassau.” I have also received a specimen of Aptychus from my friend Mr. John Edward Lee, F.G.S., of Torquay, sent to him by Prof. Ferd. Roemer, of Breslau, and labelled “Aptychopsis, sp. = operculum of Goniatites intumescens. Upper Devonian, Bicken, near Herborn, Nassau,” in Dr. Roemer's own handwriting.

^{page 345 note 2} SeeGeol. Mag. 1882, 12. II. Vol.IX. PI. IX. Fig. 13, p. 388.Google Scholar

^{page 345 note 3} See “Ueber deutsche oberdevonische Crustaceen von. J. M. Clarke, zur zeit in Göttingen,” Tafel. iv. fig. 2, N. Jahrbuch f. Min. etc. 1884, bd. i. p. 181.Google Scholar

^{page 345 note 4} Zeitschr. der Deutsch. Geol. Gesellsch. bd. xxxiv. p. 819.Google Scholar

^{page 346 note 1} Geol. Mag. 1883, Decade II. Vol.X. pp. 461–464.Google ScholarOp. cit. 1884, Decade III. Vol.I. pp. 348–356, and more fully in Brit. Assoc. Reports, Southport, 1883, and Montreal, 1884, Section C. Geology.Google Scholar

^{page 347 note 1} Prof. A. von Koenen, replying to Herr Dames, on behalf of Mr. J. M. Clarke, very justly observes, “I cannot see that this at all meets the argument, since the relative age of strata is of altogether little influence on the preservation of fossils; on the other hand, there are plenty of examples in which fossil animals have been furnished with hard, horny and even calcareous parts which are wanting in their nearest recent analogues. I will only recall here Aptychus and Anaptychus, von Koenen.” (N. Jahrbuch ii. Bd. i. Heft. 1884, p. 45.).

^{page 348 note 1} The potentiality of a form to attain to a higher existence seems to be mistaken here for actuality. It is the story of the French soldier with the marshal's baton in his knapsack and the American boy who feels within him the potentiality of becoming some dayPresident!

^{page 348 note 2} For a very full and admirable account of Nebalia see the 12th Annual Report of the United States Geological Surveys, Part I. Geology, Palæontology and Zoology, 8vo; 1883 (Washington),“A Monograph of the Phyllopod Crustacea of North America, with remarks on the order Phyllocarida” by Packard, A. S., jun., pp. 295–592 and plates i.–xxxix. See also the “American Naturalist” for Oct Nov and Dec. 1882, vol.xvi. pp. 785, 861, 945.Google Scholar

^{page 348 note 3} Pedunculated eyes are also present in Branchipus and Artemia, so that the stalked eyes of Nebaliacan hardly be regarded as an essential character.

^{page 349 note 1} The Devonian Dithyrocaris Neptuni of Hall must have been some two feet or perhaps more in length.

^{page 349 note 2} The abdomen is nine-jointed, unless the last somite be considered as the telson (it is post-anal). It is a loag and slender segment, and bears two yery long narrow setigerous cercopods, closely resembling those of the Copepoda.

^{page 350 note 1} Clans, translated by Sedgwick (Cambridge), p. 448, 8vo., 1884.Google Scholar

^{page 350 note 2} Ibid., in a footnote to p. 448. Leptostraca.—The Leptostraca (Clans) are thus defined: “Crustacea with thin skins, mostly bivalved, and with carapaces under which the body-rings remain separate as free body-segments ”(Zittel's Handbuch der Palæontologie, July, 1885, i. Band, ii. Abth., iv. Lief. p. 655.)

^{page 351 note 1} American Naturalist, 1882, vol.xvi. p. 951; and Monograph Amer, N.. Phyllopods, etc, 1883, pp. 447–8.Google Scholar

^{page 351 note 2} Packard.

^{page 351 note 3} Dr. Packard writes, “There is little to indicate that the Schizopods (Mysis, etc.) have descended from a Nebalia-like form, but rather from some accelerated zoëa form; while the Phyllocarida have had no Decapod-blood in them, so to say, but have descended by a separate line from Copepod-like ancestors, and culminated, and even began to disappear, before any Malacostraca, at least in any numbers, appeared” (American Naturalist, 1882, vol.xvi. p. 873).Google Scholar

^{page 351 note 4} Claus in Siebold and Kolliker's Zeitechrift, xxii. 1872, p. 329.Google Scholar