60 SUMMARY OF CURRENT RESEARCHES RELATING TO 



twenty-two chromosomes being invariably present. The individual pro- 

 duced shows external morphological characters similar to those of the 

 product of the fertilized gamete ; but the fate of the apogamous indi- 

 vidual was not determined. 



Iridescent Floridese.* — F. C. von Faber writes on the organization 



and development of the iridescent bodies of Florideae. His investiga- 

 tions were made on species of Nitophyllum and Taenioma, collected in 

 the Malay Archipelago. He finds that they show in intensive light a 

 peculiar steel-blue gleam which gradually disappears if the alga is exposed 

 to a weaker light. This gleam, which has been observed in many other 

 Floridese by other workers, is caused by iridescent bodies in the cells. 

 They are able to move phototactically, are positively phototactic, and in 

 intensive light they glide to the outer wall of the cell, where they act as 

 a kind of curtain. The chromatophores, like the iridescent bodies, show 

 amoeboid movements, and are negatively phototactic ; in intensive light 

 they range themselves in profile. The iridescent bodies have a protein 

 nature of a distinct structure ; under the influence of strong light small 

 globular bodies arise in them which apparently represent a product of 

 assimilation and are the true cause of the iridescence. In diffused light 

 these globular bodies disappear and the stalk-like portions withdraw to 

 the side walls of the cell. The stroma of the iridescent bodies is, there- 

 fore, not destroyed, but has the power in intensive light of returning to 

 the outer wall, where, under the influence of light, the globular bodies 

 may be again formed. The iridescent bodies arise from the same original 

 material as the chromatophores. Small spindle-shaped bodies are formed 

 in the apical cells and even in the tetraspores, some of which develop into 

 chromatophores, some into iridescent bodies. The latter act as light- 

 reflectors probably to weaken off not only the chemical but also the 

 thermal effect. This reflection is worked on a simple physical principle, 

 that of the clouded media. The structure of the bodies which are in 

 the act of protecting from light show that they disperse the short- waved 

 rays- the blue. Thus the light reflected from these bodies has a bluish 

 colour. 



Irish Marine Algae. f — A. D.Cotton publishes a list of 120 marine 

 algre collected by Praeger at Saltees off the south coast of county 

 Wexford. Previously only 63 species had been recorded for the region. 

 Notes on several of the records add to the interest of this paper, which, 

 taken in connexion with the Clare Island report by the same author, 

 forms a valuable addition to British marine botany. The microscopic 

 fungus Mycosphserplla Ascophylli Cotton, was present in the receptacles of 

 Ascopliyllum. 



Marine Algse4 — Gr. B. de Toni publishes notes on three species of 

 marine algrc, JEodes marginata Schmitz, Sebdoaia Monardiana Berth., 

 and Neurocaulon reniforme Zan. He discusses their history, distribution, 

 habit, reproductive organs where known, and the time of year when 



* Zeitschr. Bot., v. (1913) pp. 801-20 (1 pi.). 



t Irish Naturalist, xxii. (1913) pp. 195-8. 



X It. Coinitato Talassografico Italiano, Memoria xxx. (1918) 11 pp. 



