386 Herman Friele 
Boos use = N, 
venture to express any certainty of opinion as to their being 
mature forms however, but an opened shellthat disclosed a pair 
of rudimental, thin lamelle, did not appear to indicate that 
such be the case. 
Bergen June 1877. 
2. 
EXPLANATION OF THE PLATES. 
Tab. 1, Fig. 1, 1a. Waldheimia cranium juv. The first stage with 
a coherent apophysis. 
Fig. 2, 22. Waldheimia cranium a little further advanced spe- 
cimen. 
Fig, 2b. Waldheimia cranium the Same: a lamellæ, b the 
vertical walls, c the tube. 
Fig. 3, 32, 3p Waldheimia eranium «opening of the posterior end 
of the tube.« 
Fig. 4. Waldheimia cranium «The united lamelle begin to 
split. « 
Tab. 2, Fig. 5. Waldheimia cranium. «Perforation of the lateral 
walls. « 
Fig 2 | Waldheimia cranium. «Connection with septum is 
NE broken.« 
Tab. 3, Fig. 8. Waldheimia cranium. «The hinder connection be- 
tween the upper and lower parts is severed.« 
Fig. 9 and 10, Waldheimia cranium. The lamel-processes separa- 
ted.« 
Fig ll. W. cranium almost mature. 
» 1to4. Very young specimens of W.cranium. 
brandt: »» W. sepligera. 
Pa. Side view of a very young W. cranium. 
EE Gwynia capsula. 
Tab. 4, ,„ 12 to 14. Different stages of youug W. septigera Lov. 
Tab. 5414, MAS ov 
Tab. 6. „lab. 2. Two specimens of Terebratella spitzbergensis Dav. 
from the Norw. north-atlantic exp. 1876. 
