220 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
Saltonella saltans g. et sp. n. forms a very simple geometrical figure, 
and, in optical section, is semicircular, triangular, quadrangular or 
pentagonal. It neither forms pseudopodia in the ordinary sense or 
exhibits the sac-like flowing movement of some Amoebae. Saltonella 
ordinarily lies still, but of a sudden a piece springs forwards as much 
as the diameter of the body, and then there is a pause of uncertain 
duration. The author was unable to assure himself of the mechanism 
of this hopping movement, but thinks it may be due to a momentary 
powerful contraction. There is no differentiation into ectoplasm and 
endoplasm. It is not impossible that this organism is only a develop- 
mental stage of some other form. 
Eickenia rotunda g et sp. n. has much resemblance to the Phycomy- 
cetes, and is, perhaps, not a Ehizopod at all. No true pseudopodia were 
observed. It has a distinct membrane-like tegumentary layer, which is 
colourless and transparent. It moves slowly, but may have another 
stage in which it is more active. 
The only Heliozoon now described by the author is Mastigophrys 
radians g. et sp. n., which was found in an infusion of plants. It has a 
pretty thick investing layer, in which there are no isolated skeletal 
parts. A single Choanoflagellate is also briefly described, which Dr. 
Frenzel calls Diplosiga socialis g. et sp. n. ; in its general appearance it 
resembles Codonodesmus or Desmerella. Suetorella ciliata g. et sp. n. is a 
Suctorian which is briefly described, and, in conclusion, there are obser- 
vations on two new forms of Protozo a, wdiose systematic position is 
obscure ; one is named Peitiada mirabilis and the other Microhydrella 
tentaculata. 
Zoochlorellse.* — Herr A Famintzin concludes that the zoochlorellae 
are symbiotic forms of the Protococcus- like Chlorella vulgaris which 
Beyerinck and he discovered living freely. The free-living Alga and 
the isolated zoochlorellte of Paramsecium bursaria, Stijlonichia , and 
Stentor can live and divide in solutions of inorganic salts. The symbio- 
sis is complex ; the Algae decompose carbonic acid in the light and afford 
abundant oxygen to the surrounding plasma ; in the light they flourish 
well within the animals, but in darkness and sometimes in other 
(unanalysed) conditions they are more or less digested or expelled ; 
they certainly may be used as food by the Infusorians in w’hich they 
live. Three species, “ readily distinguishable by their dimensions,” are 
known : — Zoochlorella parasitica (1 • 5-3 p in diameter) ; Z. conductrix 
(3-6 p), and Z. maxima (12 p). 
Elsewhere f Herr Famintzin explains why he did not in his history 
of the subject take account of Sckewiakoff s observations on infecting 
Frontonia leucas with zcochlorellre ; he regards these observations as 
inconclusive. The manner in which the symbiotic union is effected 
remains obscure. 
Trichosphaerium Sieboldii.^ — Prof. P. Greed" notices that he de- 
scribed in 1869 this remarkable Rbizopod which Schneider named in 
1878. He corroborates some of his original observations, that the 
* Mem. Acad. Imp. St. Pe'tersbourg, xxxviii. (1891) No. 4, pp 1— 1G (1 pi.). 
t Biol. Centralbl., xii. (1892) pp. 51-4. 
j Zuol. Auzeig., xv. (1S91) pp. 60 64. 
