. Dansk botanisk arkiv. Plants; Plants -- Denmark. F. Børgesen: Rhodophyceæ of the Danish W. Indies. 351 found them a few times in the coherent tissue. They occur in small sori; later on these sori often merge into smaller groups. When they are found in the coherent tissue the sori, too, merge into rather large groups. When the tetrasporangia are ripe they become free through holes formed by the bursting of the covering cells; the net gradually dies away and is dissolved. In this way the coherent part of thallus becomes free and is able to give rise to new plants as mentioned above. SvEDELius
. Dansk botanisk arkiv. Plants; Plants -- Denmark. F. Børgesen: Rhodophyceæ of the Danish W. Indies. 351 found them a few times in the coherent tissue. They occur in small sori; later on these sori often merge into smaller groups. When they are found in the coherent tissue the sori, too, merge into rather large groups. When the tetrasporangia are ripe they become free through holes formed by the bursting of the covering cells; the net gradually dies away and is dissolved. In this way the coherent part of thallus becomes free and is able to give rise to new plants as mentioned above. SvEDELius has found male plants in the material examined by him. The antheridial stands occur upon the sides of the lamella in the net as roundish, mostly definite sori (com- pare SvEDELius, 1. c, p. 66, fig. 49); some- times it happens that some of the antheridial groups become connected through the fertilization of the tissue between them. I have not found cystocarpic plants. When the plant grows in shallow water it is rather robust, the thallus is broad and proportionally short. Sometimes it covers smaller algæ e. g. Hypnea, quite densely, forming together with these, roundish tufts. In specimens from deep water on the other hand the thallus is thin, elongated and narrow. The meshes in the net are large. The lamellæ are thin, and proportionally few cross-beams are found. Secondary longitudinal lamellæ were also found in some of the deep water specimens. This species was found in shallow water in somewhat sheltered localities and in deep water in the more open sea down to a depth of about 30 meters. It had tetrasporangia and antheri- dial stands in the months January-—March. St. Croix: Lt. Princess, here often washed ashore; near Buck Island (about 10 meters). St. Jan: In the sound between this island and St. Thomas in several places. Geogr. Distrib.: West Fig. 346. J. Ag Martensia Pavonia Part oi the net with tetrasporangia. (About 70:1).. Please note that these images
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