M. K. A. Zittel on Fossil Lithistidm. 475 



Allied to the above are : — 



4. Siplionxa prolifera^ clavata, acuta, polycephala, difformis, 

 coronata, acauUsj and Cupulina elata, poce7/?i»i, latiosculata, 

 glomerata, rJiysosiyongioides, elongata, parallela, jicoidea, capi- 

 tata, and acaulis, Court. Ep. xxix., xxx. 



5. Siphonta ternata, Reuss, Bohm. Kr. xvii. 1, 3. Turo- 

 nian. 



6. Jerea excavata, Mich. Ic. xxxiii. 3, xxxix. 2. 

 Polypothecia pictonica, Micli. ib. xxxvii. 1. 



Jerea tuberosa, Micli. ib. xxxix. 3. 



Rhi/sosponffia pictonica^ patei'cefonnis, cyathiformis, vestita, crassa, 



elongata, setniglobosa, clavata, attenuata, truiicata, costata, and digi- 



tata, Court. Ep. i.-iv. 



7. Siphonta midtiformisj Bronn, Leth. Geogn. xxvii. 20. 

 Peine. 



Marginospongia, D'Orb. 



(Prodr. ii. p. 187.) 



Alcyonmm, Lamx. 

 Chenendopora p. p., Micli. 

 Maryinojerea^ From. 

 Marginospongia, Placojerea, Pom. 



Sponge cup- or funnel-shaped, stalked. Upper margin 

 with numerous round apertures of tubular vertical canals, 

 which traverse the whole wall and the stalk. Skeleton ? Only 

 in the Cretaceous. 



1. Alcyonium infundibidum, Lamx. 1830 (teste D'Orb.). 

 Chenendopora Parki7isoni, Mich. Ic. xxxi. 1. Cenomanian. 



2. Marginospongia irregularis, D'Orb. Prodr. Et. 22, 

 no. 1500. Senonian. 



?3. Jerea Desnoyersi, Mich. Ic. xxxix. 1. 



Nelumbia, Pom. 

 (Pal. d'Oran, p. 194.) 

 Polystoma p. p., Oom-t. 



Sponge clavate, stalked ; vertex truncate or with a slight 

 depression, covered with round ostia of vertical canals, which 

 do not penetrate very deeply into the sponge-body. Sides 

 with scattered depressions, into which open short, tortuous or 

 straight transverse canals. According to Courtiller the sponge 

 is sometimes covered with a delicate siliceous skin. Skeleton 

 as in Jerea, of which this is perhaps only a section. The genus 

 is limited to the Upper Cretaceous. Courtiller [l. c. pi. xv.) 

 figures several forms, probably belonging to a single species, 

 as constituting a section of his genus Polystoma. 



