592 SUMMARY OF CURRENT RESEARCHES RELATING TO 



of many insects, the microspores and megaspores of Selaginella, the two 

 generations in Dictyota, the life-cycles in Foraminifera and the malaria 

 Protozoa. External conditions may have their value as orientating 

 stimuli. 



Force Exerted by Growing Plants.*— G. E. Stone writes about 

 the power of growth exhibited by ostrich ferns {Onocha Struthiopteris) 

 around his house. Young shoots frequently force their way up 

 through an exceptionally hard tar-concrete pavement 2i-3 in. thick. 

 By experiments made with a weighted lever he estimates that the 

 young shoots exert a force of about 190 lb. upon the concrete. He 

 cites other instances of the force exerted by growing plants. 



Sporophyll of Lycopodium inundatum.t — M. G. Sykes publishes a 

 note on the sporophyll of Lycopodium inundatum in defence of her 

 position, adopted in her recent paper on the morphology of the 

 sporangium- bearing organs of the genus Lycopodium, against the 

 criticism of W. H. Lang. The disputants had used the same definition 

 in somewhat different senses. 



Mesozoic Equisetales.J — T. G. Halle publishes an account of the 

 Mesozoic Equisetales of Sweden, in the Upper Triassic and Lower 

 Jurassic. He describes the stems and cones of several species, and 

 makes the new genus Neocalamites, possessed of characters partly like 

 those of Calamites, partly of Equisetum. The spores of Equisetites 

 lack the elaters of Equisetum, and have the triradiate sculpture 

 described for the megaspores and microspores of Calamites. 



Lastrea remota in Ireland. § — R. Lloyd Praeger gives an account 

 of a fern which he found at Dalystown in south-east Galway in 1898, 

 and has kept under cultivation ever since. His conviction that it is 

 Lastrea remota has recently been confirmed by Dr. F. "W. Stansfield. 

 L. remota was first discovered in Germany in 1843, and has been rather 

 a puzzle to botanists, having been referred to L. Filix-mas, L. spinulosa, 

 and L. dilatata. It is now regarded as a hybrid of the first two of 

 those species, a view which is in keeping with its curiously restricted 

 range. Praeger shows that it is found in the vicinity of the two 

 parent species, and points out how it resembles and differs from those 

 species. He cites some interesting passages from literature about it. 



Spanish Ferns. ||- — P. B. Merino publishes some notes on the ferns 

 of Galicia. He gives a list of 31 species grouped in 18 genera, 

 including 8 additions to the flora of Galicia, which contains 70 p.c. of 

 the species recorded for the whole of Spain. 



F. de las Barras 1[ publishes some notes on the cultivation of fern- 

 spores, methods for which he has recently been studying in England. 



* Bull. Torrey Bot. Club, xxxvi. (1909) pp. 220-5 (figs.). 

 t New Phytologist, viii. (1909) pp. 143-5 (figs.). 



X K. Svensk. Vet. Akad. Handl., xliii. No. 1 (1908). See also Bot. Gaz., xlvii. 

 (1909) p. 424. § Irish Naturalist, xviii. (1909) pp. 151-3. 



|| Bol. R. Soc. Espaiiola Hist. Nat., ix. (1909) pp. 188-91. 

 1 Torn, cit., pp. 199-206 (figs.). 



