268 SUMMARY OF CURRENT RESEARCHES RELATING TO 



fragmentation ; they accumulate reserve granules ; they lose all trace 

 of nucleus and chromatin ; they are devoured by phagocytes ; and a 

 minute sclerotic scar is finally left. 



Encystation in Stylonichia pustulata.*— X. Fermor calls attention 

 to the readiness with which this Infusorian forms a cyst when there is a 

 slight change in the external conditions. He finds, however, that the 

 encystation has more than a protective significance. By studying the 

 condition of the nucleus during the encystment he has convinced him- 

 self that there is a process of nuclear recuperation, which gives the 

 Infusorian a new lease of life and allows it to go on dividing. Usually 

 this recuperation is effected by conjugation, but in Fermor's culture there 

 was no conjugation. The exhausted nucleus was recuperated in en- 

 cystation. 



Balantidium coli.t— E. L. Walker has made a study of this parasite 

 which is relatively common in the Philippines. The same species occurs 

 in man and pig, and it was transferred to monkeys in 70 p.c. of the 

 cases experimented on. The parasite can produce intestinal abscesses 

 and dysentery. The pig is the chief source of man's infection. 



Studies of Trypanosomes4— J. Firmino Sant'And .dves an account 

 of observations on Trypanosomas in Portuguese East Africa, and deals § 

 especially with the non-flagellate forms of Trypanosoma rhodiense. 



Infusorians of Peat-bogs.||— G. Mermod has made a careful study 

 of the Infusorian fauna in peat-bogs on the Jura mountains above a 

 level of 1000 metres. He found seventy-two species and varieties, and 

 twenty-eight of these were not found elsewhere. But few of these can 

 be regarded as special to peat-bogs. 



New Infusorians from the Lake of Geneva.1T— E. Andre describes 

 some new pelagic forms— Belonophrya pelagica g. etsp. n., in the vicinity 

 of Holophrya ; Crobylura pelagica g. et sp. n., which at first sight sug- 

 gests Urotricha, but approaches in "the mouth structure to Enchelys and 

 Spathidium ; and Lionotus gandolfii sp. n. 



Reproduction of Hypotriclious Infusorians.**— G. A. Baitsell has 

 studied the so-called life-cycle in Oxytricha fallax and Pleurotricha 

 lanceolata, seeking to determine if it could be eliminated by altered 

 culture conditions. He used a "constant" medium of : 025 p.c. 

 solution of Liebig's beef extract, a hay infusion medium, and a " varied 

 environment" medium. The study of the graphs in all the daily 

 isolation cultures of both species reveals what might be termed typical 

 " life-cycles." At the beginning the animals gave every evidence of a 



* 



Zool. Anzeig., xlii. (1913) pp. 380-4 (4 figs.), 

 t Philippine Journ. Sci., viii. (1913) pp. 333-47 (7 pis.). 

 X Arquiv. Higiene Patol. Exot. Lisboa, iv. (1913) pp. 1-50 (1 map). 

 § Arquiv. Higiene Patol. Exot. Lisboa, iv. (1913) pp. 77-105 (3 pis.). 

 || Rev. Suisse Zool., xxii. (1914) pp. 31-114 (2 pis.). 

 i Rev. Suisse Zool., xxii. (1914) pp. 179-93 (4 figs.). 

 ** Journ. Exper. Zool., xvi. (1914) pp. 211-34 (1 pi. and 5 figs.). 



