349 
many paraspores, but some of them at the same time disporangia and tetrasporangia, 
though in rather small quantity and partly anomalous. Two specimens were found at 
Trindelen one of which bore only 
paraspores, the other only dispor- 
angia, and specimens recently 
collected at Trindelen in October 
bore only tetrasporangia. 
The tetrasporangia are borne 
on the inner side, more rarely on 
the flanks of the upper branches; 
they are sessile or are sometimes 
borne on a unicellular stalk, very 
rarely on a twocelled one (fig. 
278A). The sporangium-bearing 
joints often bear two or even three 
Be o ao Fig. 277 
sporangia in a longitudinal row, j D UN PE calle 
ss Seirospora Griffithsiana. Tetrasporangia. A, B young, still uninu- 
the youngest lowermost, sometimes cleated. C, with four nuclei. D division accomplished. 350 : 1. 
a sterile branch too. The tetra- 
sporangia are 60—77 w long, 42—53 u broad. The outer wall has two layers, each 
consisting of a firmer outer layer and a soft, gelatinous inner layer. These two layers 
are not present from the first; the inner one appears only shortly before the division 
of the sporangi- 
um. The division 
Was in some 
cases regular, te- 
trahedrical (fig. 
277 D), in others 
it was irregular, 
and sometimes 
more than 4 spo- 
res were present 
(fig. 278). Accor- 
ding to SCHMITZ 
(1893, p.277) the 
sporangia in Sei- 
rospora are paa- 
rig getheilt (mit 
zwei gekreuzten 
Paaren von Sporen) oder zweitheilig (mit gerader oder sattelförmig verbogener Thei- 
lungsfläche) oder tetraédrisch getheilt”. The most regularly divided tetrasporangium 
observed by me was evidently tetrahedrically divided (fig. 277 B). Regularly cruciate- 
ly divided tetrasporangia were not met with. 
D. K. D. Vidensk. Selsk. Skr., 7. Række, naturvidensk. og mathem. Afd. VII. 3. 15 
Fig. 278. 
Seirospora Griffithsiana. Irregularly divided tetrasporangia. A—D 190:1. E 200:1. F 350:1. 
