373 
genus Ceramium is said in the systematical works (Kür- 
ZING, J. AGARDH, Hauck) to be tetrahedral (triangular) 
and most of the pictures of Ktrzinc and Harvey are in 
accordance with this statement. In Kiitzing’s figure of 
C. rubrum (Tab. phyc. XIII pl. 4), however, the oblong \ / 
sporangia are shown divided by a transversal and a vert- 
ical wall. HENN. PETERSEN does not mention the mode of am D pins 
division, but his picture of C. strictum (1908 fig. IV, 1)  tetrasporangium seen from three 
shows very clearly a similar rectangular division, while nie Zu 
the mode of division is not quite clear in his fig. III, 2 of 
C. tenuissimum. CoLLıns and Hervey! describe a new 
species C. cruciatum in 1917, the sporangia of which 
are “cruciate, sometimes regularly, sometimes decuss- 
ately”. And recently Mrs. WEBER-van BOSSE” describes 
another new species C. cingulatum with a similar division 
of the sporangia. As I have myself found sporangia 
Fig. 311. with rectangular division in C. vertebrale (figs. 310, 
Ceramium diaphanum. Tetraspore 322), C. septentrionale a. o. species but on the other 
mother-cells, dividing. Only two, resp. hand have also ascertained the occurrence of tetra- 
three nuclei were present in the sect- Er 2 I 5 ER 
ions. In A tetrahedrical division. 390:1. hedral division in Danish species (e. gr. C. tenuissi- 
Fig. 312. 
Ceramium rubrum. Tetrasporangia in division. A—C after the division of the nuclei but before the division of the 
cell. F two sections of the same sporangium. 340 :1. 
! The Algae of Bermuda. Proceed. Amer. Acad. Vol. LIIL No. 1. Cambridge 1917, p. 144. 
? Liste des Algues du Siboga. III Rhodophyceae. 2° partie. Leiden 1923, p. 332. 
D.K.D. Vidensk. Selsk. Skr., 7. Række, naturvidensk. og mathem. Afd. VII. 3. 48 
