58 SUMMARY OF CURRENT RESEARCHES RELATING TO 



published for chromosomes in any species of Spirogyra, although a 

 comparative study of plates of other investigators indicates that these 

 are the bodies heretofore designated as chromosomes. 3. This spireme 

 in the pachyneme-stage is composed of deeply-stained short filaments, 

 intermixed with material of a granular nature. There is evidence that 

 this granular material was derived from the nucleolus, the filamentous 

 from the nuclear network. 4. These two materials amalgamate to 

 form one of intensive staining capacity. The amalgamated material 

 retains the spireme form. This spireme as a whole is spherical ; later it 

 elongates, becoming cylindrical. Cross-sections of the loops reveal their 

 tubular structure. 5. This spireme does not appear to split either 

 tiansversely or longitudinally, but separates at various points as would 

 a viscid mass if pulled in opposite directions. Fourteen or more 

 tubular chromosomes for each daughter-nucleus result from the elonga- 

 tion of the coils of the spireme. These are not to be considered 

 "pseudo-chromosomes." 6. At this stage, and subsequently, chromidia 

 are discharged into the cytoplasm. It is probable that these chromidia 

 are concerned in the development of pyrenoids. 7. There is no evi- 

 dence throughout the karyokinesis of an equational division of auto- 

 nomous bodies. The advantage of this form of division over direct 

 divisions appears to be in the opportunity for escape of the chromidia 

 from the nucleus. 8. Spirogyra crassa does not, in the behaviour of 

 its nucleus in karyokinesis, present a unique case, for the stages can be 

 homologized with similar stages in Allium, as typical of the higher 

 plants. 



Kaplosiphon filiformis.* — K. Yendo has made a thorough exam- 

 ination of Ruprecht's type-material of this species, preserved at St. 

 Petersburg, and finds it consists of four different species. Three of 

 these are already known under other names. The fourth is here de- 

 scribed as forming the type of a new genus, Ruprecktietta. The differ- 

 ences between the characters of Ruprecht's plants are discussed, and 

 the synonymy given of the species to which they belong. 



Melbourne Fresh-water Algae. f — A. I). Hardy writes a short 

 account of some algae of the Zoological Cardens, Melbourne, collected 

 from pools supplied from the Yan Yean reservoir and the watershed of 

 the Maroondah. The pools are all shallow with no conspicious benthos. 

 In March 1910 Botryococcus Braunii was visible at the surface ; and 

 diffused in abundance were Scenedesmus quadricauda, Merismopedia 

 glauca and Ankistrodesmus quater/ws, the latter hitherto recorded only 

 from Burmah. These specimens are discussed, and theories put forward 

 as to how they reached the Melbourne ponds. The author suggests the 

 foreign birds from the Calcutta market as the possible carriers of the 

 spores in dried mud on the legs. Twenty-three species in all are re- 

 corded from the ponds. For convenience the author adds a note on 

 Euglena spirogyra, here recorded for the first time from the southern 

 hemisphere. Peculiarities in several of the species are figured. 



* Trav. Mus. Bot. Acad. Imp. Sci. St. Petersbourg, x. (1913) pp. 114-21. 

 t Victorian Naturalist, xxx. (1913) pp. 89-95 (1 pi.). 



