72 SUMMARY OF CURRENT RESEARCHES RELATING TO 



sarcothecse; Plumularia turgida, P. caliculata, P. alata and P. aurita 

 are also new. 



Aglaophenia sinuosa has remarkable hydrothecas, in that they have 

 both the anterior and posterior intrathecal ridges fully developed and 

 forming two partitions which project in opposite directions ; A. macro- 

 carpa, A. phyllocarpa, and A. (?) whiteleggei are new. 



Additional notes and corrections are made to the descriptions of 

 Australian Hydroids which have been published by Dr. v. Lendenfeld. 



Protozoa. 



Protozoa on Mosses of Plants.* — Prof. L. Maggi has studied the 

 Protozoa which occur on the mosses growing on plants. He found no 

 less than twenty-one forms : — Amoeba hracMata, A. diffluens, A. radiosa, 

 A. polypodia, A. anthyllion n. sp., A. velifera, A. sp. (?), Coryeia dujardinii, 

 AmpMzonella violacea, JSyalodiscus hyalinus n. sp., Arcella vulgaris, 

 A. aureola n. sp., Difflugia sp. (?), Eughjpha tuhereulata, E. alveolata, 

 E. zonata n. sp., Cryptomonas (lagenella) inflata, Cyclidium glaucoma, 

 Amphileptus sp. (?), Chilodon cucullulus, Oxytricha sp. (?). 



The same forms are very widely distributed. Protective encystation 

 was very frequently observed. The author speaks of some cases of 

 apparent " mimetism," e. g. the " mimetisme homochrome " of the green 

 endoplasm of Amoeha velifera. It is probable that some forms, as Buck 

 reports of Lecythium hyalinum, are parasitic on infusorians, or rotifers, 

 or other organisms sheltering in the moss. Diatoms, bacteria, monads, 

 pollen, spores, &c., may form part of the food-supply. What looked 

 like internal gemmation in Arcella aureola is described. The author 

 claims no priority in thus calling attention to the moss fauna, but only 

 aims at extending the observations of Dujardin and others. 



Multiplication of Ciliated Infusoria.f — M. E. Maupas has published 

 a detailed account of his observations on the multiplication of Ciliated 

 Infusoria, a brief description of which appeared some time since.J 



They present great differences in the faculty of reproduction ; if we 

 look at the matter in a comparative way and represent Glaucoma 

 scintillans, which is the most fertile of the forms examined, as 1 to 1, 

 Paramsecium aurelia has the formula 1 to 5, P. hursaria 1 to 8, and 

 Spirostomum teres 1 to 10. The three causes previously assigned — 

 quality and quantity of food, temperature, and alimentary adaptation — 

 do not appear to be sufficient. We must recognize further the special 

 temperament of each species ; their differences depend on minute dif- 

 ferences of molecular constitution which are at present beyond our 

 means of investigation. Light appears to have no influence on the 

 growth and multiplication of these infusorians. 



The belief that the fissiparous faculty of these organisms is modified 

 by conjugation, and that this act strengthens and accelerates it, does not 

 seem to M. Maupas to be justified by the facts observed. He has made 

 daily observations on five species, and has not been able to discover the 

 least differences in the successive generations of divided forms ; indi- 

 viduals behave in just the same way, whether or no there has recently 

 been a conjugation. 



* Arch. Ital. Biol., x. (1888) pp. 184-9. 



t Arch. Zool. Expe'r. et Gen., v:. (1888) pp. 165-277 (4 pis.). 



X See this Journal, 1887, p. 414. 



