408 CANADIASf MICRO-PAL. EONTOLOUY. 



10. TkICOLOC^AFSA DoWLINGI, 11. sp. 



Plate XY., fig. 5. 



.Shell ovate, smooth, with upper' slight, and lower deep stricture 

 Relative lengths of the three joints, 1:4:6; relative bi-eadths, 1:3: 5. 

 Cephalis hemispherical, hy^dine, without pores. Thorax quite spheri- 

 cal with from seven to eight oblique rows of large circular pores, twice 



.as wide as the bars. Abdomen subspherical, compressed, with from 

 ten to twelve transverse rows of distant smaller circular pores. 



Dimensions: — Length of the shell, 0'214 mm. 



Breadth of the abdomen, 0*1 47 << 

 Occurrence : not frequent. 



11. Tricolocapsa Selwvni, n. sp. 



Plate XV., fig. 6. 

 >Shell wide, bottle-shaped, smooth, with two distinct strictures. Rela- 

 tive lengths of the three joints, 1:2:4. Relative breadths, 1 : 2'i) : 6. 

 Cephalis small, ovate, hyaliiie, withotit pores. Thorax hemispherical, 

 with four transverse rows of circular legular pores. Abdomen large, 

 inflated, spherical, with fi-om ten to twelve trans\erse I'ows of pores of 

 equal size. 



Dimensions :— -Length 'of the sh-ell 0'174 mm. 



Breadth of the abdomen, 137 > t 

 OccuiTence : not i-are. 



Family : Lithocampida. 



Sub-family : Stichocorida, Haeckel. 



Genus.: Dictyomitra, Ehrenberg.. 



il2. Dictyomitra Canadensis, n. sp. 



Plate XVI., tig. 1. 



Shell short, conical, campanulate, smooth, with three distinct strictures. 

 Cephalis small, spherical. Thorax small, hemispherical, with three 

 transverse rows of circular pores. Abdomen with two joints ; the 

 upper large, inflated, with eleven ti'ansverse rows of circular, regular 

 pores ; the lower joint ring-shaped with four transverse rows of pores 

 -of the same size. The wide open mouth without peristome. Relative 

 ►lengths of the four joints, 1 : 1 : 5 .: 2. Relative breadths, 1 : 1 •') : 

 5 : i)-o. 



Dimensions : — Length of the she'll, 0'23 mu. 

 Greate^st breadth, -147 -> 

 ^Occurrence : not .frequent. 



