168 FAMILY LAGENIDA. 



known from their appearance as " stag-horn processes " (ex, fig. 1 50) ; and these seem to be 

 homologous with the lobate extensions occasionally met with in " wildly-growing " Glohige- 

 rinee (^294), and still more remarkably in Carpenieria (^ 308). Although it is probable that 

 these processes are generally closed, as is surmised by Professor Williamson (ex, p. 72), yet 

 from the absence of any proper aperture to the segment from which they proceed, and from 

 their special grouping about the spot at which the aperture should be, it seems likely that 

 some of them are normally open at their extremities, and give exit to pseudopodial extensions. 

 Such " wildly-growing" specimens are probably always parasitic. — Although we have spoken 

 of the arrangement of the segments as normally biserial, yet they are sometimes so loosely 

 piled together, that three or more of them would be brought into view by a transverse 

 section. 



262. The form of the aperture, except in the cases in which the last segment takes on the 

 " wild " growth just described, is usually extremely characteristic ; being circular, with a 

 plicated margin, so as to present a regular!}' radiating form. Sometimes the centre of the 

 aperture is filled up by a plug of calcareous matter (as occasionally happens in Nodosamia), 

 so that the stoloniferous processes must pass out through a set of radiating fissures. We 

 seldom find the aperture situated at the extremity of a prolonged «'/osolenian neck ; but the 

 earlier chambers of the most transparent forms ma)' not unfrequently be seen to be furnished 

 with an ra/osolenian neck; and in the later chambers, whose apertures are not prolonged in 

 either direction, it is generally to be observed that the plica extend as far inwards as they do 

 outwards. It is a very curious fact that when an outer " wild-growing" segment extends itself 

 over the whole of the preceding series, its cavity communicates, not merely by the usual 

 radiated aperture with the antepenultimate chamber, but also by a double row of openings with 

 all the chambers which it overlaps. It is difficult to suppose that these openings existed 

 anteriorly to the overgrowth ; and we can scarcely account for their presence in any other 

 way, than that they have been formed de novo by absorption. — The appearance of the shell in 

 the younger specimens is peculiarly glassy ; the walls of the chambers being thin, and the 

 pores which traverse their vitreous substance not being so closely set as to render it opaque. 

 And it is a distinguishing characteristic of this type, that its surface-character is but little 

 modified by that exogenous deposit, which gives such marked features to the e.xterior of Lagena, 

 Nodosarince, and Uvic/erina. The shell may be simply thickened, so as to became opaque ; 

 or it may be rendered scabrous by minute granules, and these may either run together into 

 fine parallel short longitudinal riblets, or they may enlarge into beads; or they may be 

 prolonged into aciculi, which may render the surface bristly ; — but all these kinds of 

 surface-ornament are met with far more strongly marked in the other genera of the 

 family Lagenida. 



2(33. Affinities. — From the preceding description it would seem obvious that the true 

 affinity of Tolijmorpliina is on the one hand to the uniserial Nodosarina, and on the other 

 to the triserial TJvigerina. But it has a strong relation of analogy to Texfularia, the mode of 

 growth being essentially isomorphic in these two types; so that if we were to place our 

 chief reliance on that character, these two genera would have to be brought into close 

 approximation. For reasons already assigned, however, we consider the plan of increase 



