GENERAL ANATOMY. FOSSIL SPONGES. 
Spong. 13 
canal opens at one end or both 'ends of the spicule, or by perforating 
tubules reaching it from the sides; iu this case the walls of the cavity present 
the unusual character of a ragged outline. Part of the canal may also 
be simply enlarged without becoming bulbiform. In his communication, 
(7), the author describes the perforations as of two sizes, and as produced 
by probably vegetable organisms, in the form of cell-like bodies, with 
greenish protoplasm, and names this organism, which he did not detect in 
the spicules mentioned above, (6), Spongiophagus carteri. The curves of 
the enlargements of the canal do not correspond to those of the deposit of 
the silica. Each of the chief types of spicules found may have different 
forms of enlargement. The tubules which perforate the spicule from 
the exterior are cylindrical, narrow, straight, and usually perpendicular 
to the long axis of the axial canal ; they often penetrate only part of the 
way to the canal, or the surface of the spicule may be merely roughened 
by incipient erosion. In some of the various cavities described, greenish 
cells and minute bodies resembling the zoospores of Achlya^ and greenish, 
minutely granular plasmatic material, have been found. On the whole, the 
author is disposed to regard these phenomena as produced by the parasitic 
organisms, rather than by the action of carbonic acid iu solution aided 
by pressure. The spicules were contained in samples of sea-bottom from 
the deepest spot in the Pacific Ocean, o£E Japan. 
Tetronerythrin. This red colouring matter has been discovered in 
Sponges by C. De Merejkowsky, C. R. xciii. p. 1029, viz., in Suberites, 
Axinella, Chalina, Reniera. Its object is to promote oxygenation at the 
surface of the body. 
The green particles occurring in Spongillidoi are interpreted by K. 
, Brandt, SB. nat. Fr. 1881, p. 143, as unicellular Algca, and referred to 
a new genus, Zoochlorella. 
Fossil Stonges, Chief Works on. 
17. Manzoni, a. Spugne silicei della Molassa Miocenica del Bolognese. 
Atti Soc. Tosc. V. p. 173, pi. viii. 
18. Whitfield, R. P. Remarks on Dlctgophyton, and descriptions of 
new species of allied forms from the Keokuk Beds at Crawfordsville, 
Ind. Bull. Am. Mus. Nat. Hist. i. p. 10, plates iii. & iv. 
Contains, at p. 12, a note by J. W. Dawson on the Structure of a spe- 
cimen of Uphantcenia, from the collection of the American Museum of 
Natural History, New York City. 
F. Romer. Lethsea Geogno.stica. i. Stuttgart : 1880, 8vo, p. 305. 
The palaaozoic Sponges, their genera and species, are fully described. 
Aulocopium aurantium and other Sponges are well figured. 
M. Ronault. Sur les Amorphozoaires du Silurieu .inf^rieur. Paris : 
1881 (from CR. Internal. Geol. Congr. 1878.) [Not seen by Recorder.] 
1881. [vOL. XVIII.] D 4 
