316 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Thallophyta. 



Algae. 

 (By Mrs. E. S. Gepp.) 



Dysmorphococcus variabilis.* — H. Takeda gives a description and 

 figures of DysmorpJiococcus variabilis, a new genus and species of uni- 

 cellular flagellate algae belonging to the Phacote^, a sub-family of the 

 Yolvocaceffi. It was collected with a number of other alga3 in a small 

 pond in Richmond Park. The cell floats free, the protoplast is pyriform, 

 and bears a pair of equal flagella nearly twice the length of the proto- 

 plast ; it lives free within a hard, brittle, brown spherical shell pierced 

 Avith two apertures for the flagella. The chromatophore is single, green, 

 urceolate ; the stigma small, parietal ; the nucleus almost central. Pro- 

 pagation unknown. 



Scourfieldia cordiformis.t — H. Takeda describes and figures Scour- 

 fieldia cordiformis, a new Chlamydomonad from a Sphagnum marsh at 

 Keston, Kent. It differs from S. complanata in having an obovate side 

 profile. It is very small, heart-shaped in front view, slightly emarginate 

 at apex and provided with two long flagella four times the length of 

 the cell ; the chromatophore is single, green, homogeneous, and sub- 

 campanulate ; stigma and vacuoles absent ; nucleus minute and central. 

 The genus Scourfieldia is remarkable among the Chlamydomonads for 

 its normal movement backwards, that is, with the flagella behind it. 

 In Carter ia and Chlorogonium a temporary backward movement is some- 

 times observed, as also in Trachelomonas, a genus of Euglenineae. 



New Genus of Volvocaceae.| — W. R. Shaw describes a new genus, 

 Besseyospiisera, on a species described by J. H. Powers as " a second form 

 of Volrox.'" § Its position is intermediate between PJeodorina and 

 Volvox. From Fleodorina it is distinguished chiefly by having the 

 gonidia scattered among the vegetative cells, instead of being developed 

 from all the cells of the reproductive area. It differs from typical 

 Volvox in having no protoplasmic connexions between the cells, and in 

 the lateness of the first visible differentiation of the gonidia, which does 

 not appear till after birth. The author suggests that certain species of 

 " Volvox " collected in the Philippine Islands may be properly removed 

 from that genus, and that one or more of these may be proved to belong 

 to his new genus, Besseyosphaera. Diagnoses of genus and species, 

 B. Poicersi, are given. 



PlanktGn-epibiontae.ll — B. Schroder discusses the group of plaukton- 

 epibiontae described by various authors and himself. They are the 



* Ann. Bot., xxx. (1916) pp. 151-G (figs.), 

 t Ann. Bot., xxx. (1916) pp. 167-9 (figs.). 

 X Bot. Gaz., Ixi. (1916) pp. 253-4. 

 § Trans. Amer. Micr. Soc, xxvii. (1907) pp. 123-49. 



II Biol. Centralbl., xxxiv. (1914) pp. 328-34. See also Hedwigia, Iv. (1914) 

 Beibl., p. 92. 



