120 MONOGRAPH OF THE FOSSIL POLYZOA OF THE 



grooves, acute at the bottom, but rounded on the edges, between which are small pits 

 having no determinate arrangement; these, of course in casts, are represented by cor- 

 responding elevations. 



From L. contigua, this species can be distinguished by the very regular arrange- 

 ment of the cellules, and by their being, in casts, rarely if ever overlapping or in any 

 way hiding the others. In L. contigua they were so close together that the surface 

 must present somewhat of a waved appearance. Lonsdale says of that species, cells 

 in " rows parallel, not alternate," so that it must approach this very closely. We are 

 not sure that we have encountered that species, although we have a specimen which 

 corresponds with his description, except that for the cast the cells seem to have been 

 in quincunx. 



In regard to the openings laterally between the cellules, it appears more than pro- 

 bable to us that d'Orbigny, in his monograph of the fossil species, did not give them 

 the attention they deserve, since while he uses the " special pores " as a means of 

 separating his families in the suborder to which this genus belongs, he has placed 

 under Lunulites, species both with and without these openings. More recently (1854) 

 Busk, in the monograph of the species of the British Museum, (see Brit. Mus. Gatal. 

 Marine Polyzoa), has demonstrated that through these openings are protruded the 

 vibracular appendages of the colony. These organs, with the avicularia, have proved 

 to be of great use in classifying the recent species, and we conceive that the presence 

 or absence of them, not less than their position in relation to the cellule, should be of 

 generic value here. 



The type of the genus Lunulites is L. radiata, Lam., and, as figured by Goldfuss, is 

 provided with these intermediate openings, consequently, the above and the following 

 species are true Lunulites. We propose, at no very distant period, to re-examine the 

 whole subject, and believe that we will find sufficient reason for removing the true 

 Lunulites from the family Escharida;, together with some of the species of d'Orbigny's 

 two genera, Pavolunidites and Reptolumdites. The remainder, having the same cha- 

 racter of cellules, the same radiating, linear arrangement, always commencing by an 

 abortive cellule, but with no vibracular openings, will still remain in this family. 



L. interstitia, G. and H. 



Orbitolites id. Lea, Contributions, p. 191, pi. 6, f. 204. 

 Colony circular, low, conical. Cellules arranged in regular radiating lines, with 

 new lines occasionally interposed, always commencing by an abortive primo-serial 

 cellule. They also form regular annular lines. The cellules are octagonal, usually 

 somewhat elongated, the length being to the width about as five to three. The sur- 

 face is unusually open, walls thick but simple, no ornamentation. There is a faint 

 sign of division in the shape of an obsolete groove, sometimes visible between the 



