bo 
ny 
bo 
214. 
215. 
BIBLIOGRAPHY. 39 
Tremacystia, Inobolia, Trachysinia, Diaplectia, and Rhaphidonema. The author 
maintains the view of Zittel that the Pharetrones are a distinct family from 
the existing Leucones, and regards their fibrous structures as original, and 
not, as stated by Dunikowski, produced merely by fossilization. 
. 1883 Sottas, W. J. Descriptions of Fossil Sponges from the Inferior Oolite, 
with a notice of some from the Great Oolite (Quart. Jowrn. Ceol. 
Soc., vol. xxxix, pp. 541—554, Pls. XX, XXI). 
Describes as new genera of hexactinellid Sponges, Hinploca, Mastodictywm, 
Plectospyris, and Calathiscus, also a new species Leptophragma fragile. Anew 
species of lithistid, Platychonia elegans, and several species of Pharetrones, as 
well as a new genus Thamnonema, are also described. 
. 1883-84 Povra, P. Beitrige zur Kenntniss der Spongien der béhmischen 
Kreideformation. I Ab., Hexactinellide, sep. cop., pp. 1—42, Pl. 3; 
II Ab., Lithistide, sep. cop., pp. 1—45, 2 Pls. (Abhandlung. der 
Kénigl. bohm. Gesell. der Wiss., vi Folge, 12 Bd.). 
These memoirs give the results of a thorough investigation into the 
minute structures and other characters of the Sponges from the Cretaceous 
strata of Bohemia, the superficial characters of many of which had already 
appeared in the works of Reuss. Zittel’s classification is adopted. In addi- 
tion to many new species of existing genera, the following new genera of 
hexactinellids are proposed: Petalope, Synaulia, Lopanella, Botroclonium, and 
Cyrtobolia. The only new genus of lithistids is named Paropsites. Figures are 
given of the new forms and of their spicular structures. 
. 1883 Potra, P. Einige Bemerkungen itber das Gitterskelet der fossilen 
Hexactinelliden (Sitzwngsb. der Kénigl. bohm. Gesells. der Wiss. Prag. 
Jahrg. 1882, p. 378). 
Gives a detailed description of the spicular structure of this group of 
Sponges, and of its modifications in different genera. 
1884 Donixowsx1, E. Ueber Permo-Carbon. Schwiimme von Spitzbergen 
(Kongl. Svenska. Vetensk. Akad. Handl., Bd. 21, sep. cop., pp. 
1—18, Pl. LI). 
The Sponges are stated to be of a fibrous character, and the fibres are 
composed of monactinellid spicules. They are placed in a new genus, 
Pemmatites, and divided into four species and varieties. Their state of pre- 
servation is so unfavorable that there is room for doubting whether their 
true characters have been ascertained. 
1884 Zirrer, K. A. Ueber Astylospongide und Anomocladina (Newes Jahrb. 
f. Min., Bd. 11, pp. 75—80, Pls. I, II. 
From further study the author sees reason to alter his former views 
