SPONGIIDA. 
14 Spong. 
Aulocopium (jotlandicunit sp. n., Romer, 1. c. p. 313, Upper Silurian. 
Hyalostelia smithiy Young, figured and described by G. Stein MANN, 
Z. geol. Ges. xxxii. p. 395, pi. xix. fig. 5, from carboniferous limestone. 
Craticularia, sp. figured by Manzoni (17), from Miocene of Bologna. 
Aatroconia granti, g. & sp. nn., W. J. Sollas, J. Geol. Soo. xxxviii. p. 254, 
figs. 1-11, Niagara Limestone (Silurian), Cauada. Belongs to the Lyssa- 
kine section of Ilexactmellida. 
Uphantcenia, from Keokuk Beds, Indiana, determined by Dawson (18) 
to be probably a Sponge near Euplectella ; it contains cylindrical spicules. 
U. dawsoni, Whitfield, described and figured, (13) p. 16, pi. iv. figs. 
1 & 2 . 
'2 Dictijophyton caiilliforme and cylindricuni, id. spp. nn., pp. 18 & 19, 
pis. iii. & iv. fig. 3, Keokuk Beds, Indiana. Long cylindrical spicules 
were observed in cylindricum. 
R. P. Whitfield, Am. J. Sci. (3) xxii. p. 53, also calls attention to 
the close resemblance borne by the structure of Dictyophyton to that of 
Euplectella^ and expresses his opinion that it is “ of the nature of Sponges,” 
and not of that of plants. At tom. cit. p, 132, iu conjunction with J. W. 
Dawson, he describes the structure of a species of Uphantnmia. The latter 
finds it not to be identical with that of any plant known to him, but, as 
above mentioned, to resemble Euplectella more closely. He discusses the 
conditions produced iu Sponges by fossilization. 
Cyathophycus : specimens described by 0. D. Walcott, Am. J. Sci. (3) 
xxii. p, 394, and stated to strongly resemble Euplectella. 
Sponge-spicules, 3- and 6- rayed, in Upper Silurian beds in Shropshire ; 
J. Smith, Geol. Mag. (n. s.) viii. p. 73. 
W. J. Sollas, Ann. N. H. (5) vii. p. 141, fig. 1, records the identifica- 
tion of Sponge-spicules in chert from the Upper Carboniferous Lime- 
stone of Ireland ; they have au acerate form, and show the existence of 
a central canal. 
G. 0. Wallicii, in a paper entitled, “ On the Origin and Formation 
of the Flints of the Upper or White Chalk, with Observations upon 
Prof. Sollas’s paper in ‘ The Annals and Magazine of Natural History ’ 
for December, 1880,’” in Ann. N. H. (5) vii. p. 1G2, pi xi., rebuts Sollas’s 
arguments against his views [see Zool. Roc. xvii. Spang, p. 21]. He 
regards flints as formed chiefly of silex derived from Sponge-skeletons 
and spicules, which has first assumed a gelatinous colloid form. See 
also id. tom. cit. p. 261, on Siliceous Sponge-growth in the Cretaceous 
Ocean. 
The same writer, op. cit. (5) viii. p. 46, iu Supplementary Notes on the 
Flints and on the Lithological identity of the Chalk and Recent Calcare- 
ous Deposits, finds the above opinions supported by the large proportion 
(31^ to 64 per cent.) of silica contained in the material contained by 
hermetically closed flints. See also H. J. Carter,. Ann. N. H. (5) vii. 
p. 308, on the Kunker Formation of the Alluvium in India compared 
with the Flint Formation in the Chalk of England. 
List of Fossil Sponges, with localities, given in Arch. Mus. Teyl. 
(2) i. p. 231, by T. C. Winkler, as part of the Catalogue Systdma- 
tique of the Teyler Museum ; the nomenclature is pre-Zittelian. 
