26 BRITISH FOSSIL SPONGES. 



are classified, and some are shown to be similar to those described by Carter 

 from Greensand strata. 



140. 1877 Carter, H.J. On a Fossil species of Sarcohexactinellid Sponge allied to 



Hyalonema (Ann. and Mag. Nat. Hist., S. 4, vol. xx, p. 176). 

 A provisional notice of the presence of spicules of this group of Sponges in 

 Carboniferous strata. 



141. 1877 Young, J., and Young, J. On a Carboniferous Hyalonema and other 



Sponges from Ayrshire (Ann. and Mag. Nat. Hist., S. 4, vol. xx, pp. 



425—432, Pis. XIV, XV). 



Numerous detached hexactinellid spicules, with others of anomalous form, 



and portions of elongated spicular rods, are regarded as belonging to a Sponge 



of the existing genus Hyalonema. Also a fibrous Sponge in which no spicules 



could be recognised is placed in a new genus, Haplistion. 



142. 1877 Trautschold, H. Ueber Kreidefossilien Russlands (Bull, de la Soc. imp. 



des nat. de Moscou, vol. 52, p. 339, PI. vi). 

 Describes various species which are placed in the genera Cupulispongia, 

 Porospongia, and Placuntarion. Nothing is stated of their minute structures. 



143. 1877 Zittel, K. A. Studien iiber fossile Spongien. 1 Abtheil., Hexacti- 



nellidse (Abhandl. d. Jc. layer. Akad. der Wissenschaften, II CI., xiii Bd., 



pp. 1—63, Pis. I— IV). 

 Describes the systematic position, the condition of preservation, the charac- 

 ters, and the classification of fossil hexactinellids. Their skeletal structures 

 are shown to possess the closest relationship to those of recent hexactinellids 

 from the depths of the ocean, and they are very distinctly marked off from the 

 Lithistids. Two main divisions are constituted (1) Lyssakina, in which the 

 skeletal spicules are, as a rule, detached from each other, and only held in 

 position by the sarcode ; and (2) Dictyonina, in which the skeletal spicules are 

 fused together in a regular manner, so as to form a connected lattice-like mesh 

 with cubical or polyhedral interspaces. In this latter division are included the 

 following families ; Astylospongida, Euretida, Coscinoporida , Mellitionida, Ven- 

 triculitida?, Staurodermidai, Maiandrosyongidce, Callodictyonidce, and Coslopty- 

 chidce, whilst in the Lyssakina are included Monakidcz, Marshall ; Pleionakidai, 

 Mars. ; and Pollakidce, Mars. Numerous new genera are proposed and dia- 

 gnoses of them given. 



144. 1877 Zittel, K. A. Beitrage zur Systematik der fossilen Spongien (Erster 



Th.) Neues Jahrbuch, pp. 337—378, Pis. II— V). 

 For the most part a reprint from the " Studien " referred to above. 



