﻿122 CARBONIFEROUS AND PERMIAN FORAMINIFERA. 



or more triangular figures. Where the ring is absent or can only be partially traced, the 

 ends of the costse often show considerable lateral thickening, indicating the line of the 

 abortive transverse girdle. Lagena Lebouriana is the smallest of the Carboniferous 

 species of the genus, and exhibits the same slight roughening of the surface that has 

 been remarked in its fellows. Its modifications merit fuller illustration than the 

 single drawing which is given in Plate X, but the plate was already partly on the stone 

 before the specimens were discovered, and room could only be made for one additional 

 figure. 



It is with much pleasure that I associate so interesting a form with the name of my 

 friend, Mr. G. A. Lebour, F. G. S., to whose observations we owe much of our accurate 

 knowledge of the geology of the locality in which the species was found, as also of many 

 other portions of Northumberland. 



Distribution. — In the shale overlying the Great Limestone, Fourstones Quarry, 

 Northumberland . 



Genus — Nodosarina, Parker and Jones. 



Nodosaria, Glandulina, Lingulina, Frondicularia, Flabellina, Dentalina, Vaginulina, 

 Rimulina, Marginulina, Cristellaria, Bobulina, Planularia, &c, anclorum. 



General Characters. — Shell hyaline, tubuliferous, either straight, arcuate, crozier- 

 shaped, or disco-spiral ; composed of several segments arranged in one series. Pseudo- 

 podial orifice terminal and single, either central or excentric. Surface smooth, or 

 ornamented with straight raised parallel lines, either continuous or interrupted, 

 sometimes represented by spines or granules, sometimes reduced to one or more keels. 



Foraminifera pertaining to the generic type Nodosarina are less common in deposits 

 of Carboniferous and Permian age than in those of almost any subsequent geological 

 epoch, and they also exhibit a less extensive range of morphological characters ; so that 

 any lengthy exposition of the relation of the various quasi-geuQnc groups above 

 enumerated, which, with many others, have come to be included under this one 

 generic term, would be manifestly out of place. The subject has been treated 

 with much care in the ' Monograph of the Foraminifera of the Crag ' (pp. 46 et seq.), 

 and nothing that has accrued from continued observations has tended to disturb 

 the conclusions therein laid down. 1 It is sufficient for our present purpose to say that 



1 Except, perhaps, in connection with the genus Ellipsoidina, which was then included with the 

 Nodosarince. It is difficult to speak positively about so very rare a type, nor does it affect the general 

 truth of the views in question, but I am convinced from recent observations that Ellipsoidina has its 

 nearest ally in Chilostomella, and that Chilostomella is more closely related to Polymorphina than has 

 been hitherto supposed. 



