FOSSIL SPONGES. 
Spong. 9 
dictyon reticulatum^ Goldf., PachytichUma carteri, Zitt.). He also, t. c. 
p. 705, makes some remarks on Quenstedt’s recent work on Sponges, 
criticising his genera, &c., and identifying some of his figures. 
SoLLAS, in J. Geol. Soc. xxxiii. p. 790, pis. xxv. & xxvi., on the genus 
Siphonia, gives a full account of the literature of allied forms, and elabo- 
rate tables of the species which have been assigned to the genus ; con- 
siders that they may be reduced to five (figured). They agree very 
closely with the recent Lithistid^ Discodermia j)olydiscus, Boc. (figured). 
New Genera and Species. 
Pharetrospongia strahani^ Sollas (24), p. 242, pi. xi. Agrees with Des- 
macidon in having a regular fibre full of spicules ; these are acerates. 
Coprolito bed, chalk marl, Cambridgeshire. 
Haplistion, Young & Young (25), p. 428, pi. xv. figs. 31-37. Spheroidal. 
Skeleton of closely-set fibres; no spicules found. Carboniferous lime- 
stone, Cunningham Baidland. 
Chlamys magna^ iid. 1. c. Apparently a Gumminean by its large 
eccentric stellates, the only remains found. Locality as preceding (pro- 
bably not from a deep sea). 
Hyalonema smithi, \id. 1. c., is really the A canthospongia smithi of 
authors (= Serpula parallelum, McCoy). Now considered a Sponge and a 
Hyalonema from its long anchoring spicules (smooth). Carboniferous 
limestone, Cunningham Baidland (p. 426, pi. xiv.). 
Stauronema, Sollas (23). Resembles a cup-shaped Farrea, but with 
an oscular “ veil” ; carries cylindrical spined spicules (p. 1, pis. 1-5), wall 
several layers thick. 
Callodictyon, id. 1. c. Apparently a new name for Stromatopora, 
introduced as a Hexactinellid Sponge, among the Aphrocallistidm, 
Zittel (22 : the pagination is that of Abh. bayer. Ak. xiii., but see 
note as to date), characterizes the following new genera, mainly from a 
microscopic examination of forms formerly known only by superficial 
characters : — 
Tremadictyon^ = part of Spongites and Scyphia. Large serial oscula 
on inner wall ; meshes irregular ; “ veil ” over wall (p. 46). 
Cratictilaria. Differs from preceding by its cubical meshes (p. 46). 
Sphenaidax. Differs from preceding by the meandric folds of the 
wall (p. 47). 
Sporadopyle. Outer ostia scattered or in quincunx ; rest as above 
(Craticularia), (p. 47). 
Leptophragma. Wall thin ; many small ostia ; skeleton meshes 
irregular ; nodes solid (p. 48). 
PacJiyteichisma Meandric walls ; ostia internal ; meshes regular, 
with octahedral nodes (p. 49). 
Trochoholm, As preceding, but wall nodulated (p. 50). 
ScMzo[f]rhahdm. Rod -like, laterally slit up, furrowed ; rest as pre- 
ceding (p. 51). 
Rhizopoterion. Stalk branched ; radial canals into stem ; fibres with 
no axial canals (p. 51). 
