56 HENRY B. BRADY. 



a great degree their ordinary form and appearance, but tlie 

 finely cemented test is replaced by a membranous or chitl- 

 nous envelope, to which the sand-grains are adherent, or iu 

 which they are partially embedded. 



TROCHAMMINA. 



General characters . — Test thin ; composed of minute sand- 

 grains incorporated by calcareous or other inorganic cement 

 of fine texture, or embedded in a chitinous membrane ; exte- 

 rior smooth, often polished ; interior smooth or rarely reticu- 

 lated, never labyrinthic. 



Ammodiscus, Reuss. — Test free, formed of a tube of nearly 

 even diameter coiled upon itself in various ways ; sometimes 

 slightly constricted at intervals, never really septate. 



Examples: Ammodiscus incerta (d'Orb.) ; A. gordialis, 

 J. and P.; A. charoides, P. and i.; A. milioloides, P., J., 

 and K. ; A. pusilla (Geinitz) ; A. Jiliim (Schmid) ; &c. 



Trochammina, p. and J. (proper). — Test rotaliform, 

 nautiloid or trochoid, free or rarely adherent, more or less 

 distinctly septate. 



Examples : Trochammina injiata (Mont.) ; Tr. coronata, 

 nov. ; Tr. squamata, J. and P. ; Tr. tnacrescens, Brady ; 

 Tr. tridlissata, nov. ; Tr. ringens, nov. ; Tr. pauciloculaia, 

 nov. ; &c. 



HoRMOSiNA, non. — Test consisting typically of several 

 segments in a single straight or arcuate series. When the 

 primordial segment is large, growth is arrested and a lageni- 

 form test is the result. 



Examples: Hormosina glohtdifera, nov.; H. ovata, 

 nov„ ; &c. 



Webbina, d''Orhigny. — Test partially or entirely adherent ; 

 consisting of a single hemispherical, oval, or subspherical 

 chamber, with or without an adherent semi-cylindrical 

 neck ; or of a series of tent-like chambers united by adherent 

 stoloniferous tubes. 



Examples : Webhina irreguUms, d'Orb. ; W. hetnis- 

 pherica, P., J., and B. ; W. alternans, P. and J. ; W. cla- 

 vata, P. and J.; &c. 



Trochammina trullissata, n. sp. PI. V, figs. 10, ah,\\. 



Characters. — Test nautiloid, compressed, lenticular, 



somewhat excavated at the umbilicus ; composed of 



about three convolutions, of which but little more than the 



latest is visible ; peripheral margin acute or somewhat 



