214 SUMMARY OF CURRENT RESEARCHES RELATING TO 



of a single evolutive oosphere and of a spherical follicle, composed of a 

 great number of abortive oospheres, is homologous with " teleomerismes," 

 which have themselves also the value of "blasteas," and are composed 

 of eight evolutive oospheres in Fucus ; of four evolutive and four abor- 

 tive in AscophyllMti ; of two evolutive and six abortive in Felvetia; of 

 one evolutive and seven abortive in Himanthalia ; of one evolutive 

 and three abortive oospheres or polar globules in animals. 3. The 

 ontooenesis, certainlv meiotic, of the female " teleomerisme " of Volvox 

 is homologous with that meiotic ontogenesis which one calls the matura- 

 tion of the Qgg in animals. 4. The oosphere of Volvox is homologous 

 with that of animals. The peripheral follicular stratum of abortive cells 

 which envelops the oosphere of Volvox is quite comparable with the 

 group of three polar globules in animals. It is only the small number 

 and small size of these globules which gives them the appearance of 

 corpuscles rejected by the egg. Morphologically they represent plastids 

 resulting from the ontogenesis of a " blastea," a reduced ontogenesis, 

 in the Fucaceae, with three bipartitions producing eight oospheres, all 

 or partly evolutive ; and in the Animal, with two bipartitions producing 

 four oospheres, only one of which is evolutive, while the three others 

 are abortive. 



Euglena sanguinea.* — E. Naumann instances Euglena mnguinea as 

 an example of plankton production in the Swedish ponds. He uses the 

 microphotographic method of determining its quantitative occurrence at 

 Aneboda in South Sweden. The first photograph shows the alga in its 

 different stages of extension and contraction ; No. 2 shows an irregular 

 diffuse distribution (production per sq. mm. about 150) ; Xo. 3 the 

 centre of a free-floating colony of E. samjumea ; and No. 4 the micro- 

 physionomy of the red surface of the alga (production per sq. mm. 

 about 300). 



Algological Notes.f — G. S. West publishes a further instalment of 

 his Algological Notes :— xviii. Chlamydomonas microscopica is proposed 

 in place of G. gracilis for the plant described in Note xiv. xix. The 

 genus Protococcus C. Ag. (1824) having been proved by Wille to be 

 valid, the name Pleurococcvs must be dropped. Seven well-established 

 and three less definite species are enumerated, xx. Platymonas tefrathele 

 (both genus and species being new) is described. It developed 

 abundantly, in April and May 191.5, in a saltwater tank used for culti- 

 vating crabs. It belongs to the Carteiiese, a sub-family of Volvocacese. 

 XXI. Ghlamydomonm hrachyura, a new species, is described. It developed 

 in the same tank with Platymonas. C. palatina Schmidle was found in a 

 ditch at Harborne ; C. Holdereri Schmidle in a tub at Hereford ; and 

 C. Grovei, a new species, in a water-butt at Studley Castle, and at 

 Cambridge, xxii. Pteromonas angidosa Dang, and P. Takedana, a new 

 species, are described and carefully distinguished, xxxiii. An abnormal 

 form of Closterium Ehrenbergii is discussed. 



* Skrift. sodra Sveriges Fiskerforening, (1914) No. 12, 16 pp. (4 pis.). See also 

 Bot. Centralbl., cxxxi. (1916) p. 37. 



+ Journ. Bot., liv. (1916) pp. 1-10 (figs.). 



