l!faviculacea.'] infusorial animalcules. 425 



Stauroneis macidata (Bailey.) — Lanceolate or elliptical, end 

 slightly produced and rounded; sm-face punctato- striate, with a 

 large smooth central space. E-csemblcs S. punctata of Kiitzing, but 

 is larger, and has the ends not so much produced. Florida 



Sub-genus Stauhopteea. — Lorica transversely striated; median 

 aperture (umbilicus) transverse. 



S. aspera. — Hexangular ; laterally quadi'angidar ; dorsaUy navi- 

 cular; keeled; with transverse granular striae. Length 1 -216th. 

 Living, Christiania. 



S. cardinaUs. — Large, bacillar, quadi'angular, extremities not 

 attenuated, but simply rounded ; striated on the sides, transversely. 

 Length l-180th. ; often sixteen times greater than the breadth. 

 (P. 15, f. 72.) Fossil, South America, San Fiorc, See. 



S. capitata. — Ycry small, oblong ; its length twice its breadth ; 

 viewed on the back (dorsally) linear ; ventrally, constricted suddenly at 

 each end and capitate ; apices rather dilated. It has eighteen striae 

 in l-1560th. Length 1-11 52nd. Southern Ocean. 



S. granulata. — Figure bacillar, but turgid at middle ; ends obtuse ; 

 surface with transverse gi*anular strice. Length 1 -480th. Canton, 

 China. Allied to D^agUaria (?) mesotyla^ and to AchnantJies 

 ventricosa. 



S. semicruekda. — ^^^ery large ; resembles Phmidaria viridis, but has 

 the crucial umbihcus, characteristic of this sub-genus. 



S. leptocephala. — A new species discovered by Ehrenberg in earth 

 fi'om I^ew Holland. 



S. Achianthes. — i^arrowly lanceolate ; ends tapering, subacute. 

 Mexico, Newfoundland.. 



S. (?) gilla. — "ffas the form of Eunotia gihba; but is characterized 

 by its imperfect transverse umbilical band. It is, however, a doubtful 

 form. Chili. 



S. Isostauron — Styliform on its ventral aspect; laterally straight; 

 ends slightly decreasing, and widely rounded. Approaches S. cardt- 

 nalis. Labrador. (P. 15, f. 73.) 



S. Legumen. — Oblong, small ; dilated ventrally ; laterally with 

 three undidations; extremities constricted, obtuse. Berlin, Chili, 

 Cayenne. 



