SUPPLEMENT. 701 



Some of Goldfuss's Coscinoporse are represented with quadrangular 

 cells, and belong to this group ; as his generic character, cells disposed 

 in quincunx order, would exclude them from his genus. 



Defrance, Diet, des Sci. Nat., xlv., 5, and Blainville, Man., 572, pi. 68. 



GENCS TETRADIUM. DANA. 



Coralla aggregata, tubulis cellisque quadrangulatis composita, septis 

 parietibusve tenuissimis ; cettis lamellis angustis 4 stettatis. 



Coralla massive, consisting of 4-sided tubes, and cells with very thin 

 septa or parietes ; cells stellate, with 4 narrow lamellae. 



This genus is near Receptaculites, but differs in having very thin 

 parietes, and four distinct rays within the cells, one to each side. 

 The specimen answering to the description, is a fossil of uncertain 

 locality, in the collections of Yale College, New Haven. The cells 

 are about half a line in breadth. The name, from the Greek 

 four, alludes to the quadrate structure. 



GENUS THEONEA. -LAMOUROUX. 



Pumilcs. Coralla calcarea, lobulato-glomerata, et lacunosa, lobulis par- 

 vulis, et apice celliferis, inter stitiis tenuissimis kvibus, nudis; cettis 

 tubulatis, lamellis nullis. 



Quite small. Coralla calcareous, lobulato-glomerate and lacunose ; 

 cells opening at the summits of the prominences, tubular without 

 larnellee ; interstices very thin, naked, and smooth. 



The texture of the coralla is delicate tubular, and these tubes open 

 at the summits of the small lobules or prominences. The absence of 

 all traces of lamellae or transverse septa within the cells, removes the 

 species from the Actinaria. 



176 



