247 



divided and two-parted sporangia were frequently met with. In a specimen from 

 the Limfjord, sporangia were found which were irregularly divided into more than 

 4 cells (fig. 164 B). 



The antheridial conceptacles (fig. 166) occur in the same plants as the female 

 ones. They are very small, e. g. 56/^ in inner diameter, totally immersed or only 

 little prominent. The bottom is composed of one to two cell-layers. The cells of 

 the roof are often partly disorganized. The ostiole is conical or conical-cylindrical, 

 sometimes, but not always provided with a long spout resembling that in M. Lejolisii. 

 The spermatangia 



young stage with unfertilized carpogonia is shown in fig. 167 A; a number of car- 

 pogonial branches are placed on the bottom. The short cell under the carpogonium 

 is probably the auxiliary cell. After fertilization, the surrounding elongated cells 

 shown in fig. 167 A are dissolved, the developing cystocarp increasing at the peri- 

 phery. A ripe cystocarp is seen in fig. 167 D, showing a number of carpospores 

 produced at the periphery of the cystocarp, while numerous unfertilized carpogonia 

 are still visible on the middlemost part of the floor. The cystocarpic conceptacles 

 are 210—325 //. in diameter; they are of the same shape as the sporangial ones, and 

 the roof and the osliole have a similar structure. The ostiole is surrounded by 

 similar inward and upward converging filaments, which may sometimes project 

 outwards as a crown. A well developed crown is shown in fig. 167 C, where the 

 free ends of the filaments are distinctly articulated. In fig. 167 D, which shows 

 another conceptacle of the same plant, the free ends of the filaments seem to have 

 been thrown olT, for the converging filaments are only one- or Iwo-celled, and re- 



The female 



D 



conceptacles re- 

 semble the spor- 

 angial ones. A 



Fig. 166. 



Melobesia Umitata. Vertical sections of nntlieridial conceptacles. A— C from I, D from 

 Amtol't Rev. A and B, before discharge of the spermatia. D, llie ostiole is prolonged in 

 a spout. -4 and /J 650:1. C5G0:1. 



