[452] Pauli, W. u. Samec, M., Ueber Löslichkeitsbeeinflüssung von Elektrolyten durch Eiweisskörper, Biochem. Zeitschr. XVII, p. 235, 1910. Some of these results were known much earlier; cf. Fokker in Pflüger’s Archiv, VII, p. 274, 1873; also Irvine and Sims Woodhead, op. cit. p. 347.
[453] Which, in 1000 parts of ash, contains about 840 parts of phosphate and 76 parts of calcium carbonate.
[454] Cf. Dreyer, Fr., Die Principien der Gerüstbildung bei Rhizopoden, Spongien und Echinodermen, Jen. Zeitschr. XXVI, pp. 204–468, 1892.
[455] In an anomalous and very remarkable Australian sponge, just described by Professor Dendy (Nature, May 18, 1916, p. 253) under the name of Collosclerophora, the spicules are “gelatinous,” consisting of a gel of colloid silica with a high percentage of water. It is not stated whether an organic colloid is present together with the silica. These gelatinous spicules arise as exudations on the outer surface of cells, and come to lie in intercellular spaces or vesicles.
[456] Lister, in Willey’s Zoological Results, pt IV, p. 459, 1900.
[457] The peculiar spicules of Astrosclera are now said to consist of spherules, or calcospherites, of aragonite, spores of a certain red seaweed forming the nuclei, or starting-points, of the concretions (R. Kirkpatrick, Proc. R. S. LXXXIV (B), p. 579, 1911).
[458] See for instance the plates in Théel’s Monograph of the Challenger Holothuroidea; also Sollas’s Tetractinellida, p. lxi.
[459] For very numerous illustrations of the triradiate and quadriradiate spicules of the calcareous sponges, see (int. al.), papers by Dendy (Q. J. M. S. XXXV, 1893), Minchin (P. Z. S. 1904), Jenkin (P. Z. S. 1908), etc.
[460] Cf. again Bénard’s Tourbillons cellulaires, Ann. de Chimie, 1901, p. 84.
[461] Léger, Stolc and others, in Doflein’s Lehrbuch d. Protozoenkunde, 1911, p. 912.