306 
DORIS L. MACKINNON. 
disintegrating, and the “ ribs fray off, exactly as in 
Lophoinonas striata. I have seen no completely formed 
cysts nor any trace of division in the encysted state.. 
Summary. 
Whatever be the relationship of the Lophomonadidge 
with other Trichonymphids, recent research has clearly 
indicated that their affinities on the flagellate side are with 
the order Polymastigina, Doflein, and in this order with the 
family Poly mas tigid^, Biitschli. 
The genus Polymastix, Biitschli, itself shows certain 
structural features that greatly strengthen this view. While 
the comparison must not be pushed into too great detail, the 
evidence so far collected seems strong enough to make mere 
coincidence of resemblance improbable. The points of 
similarity may be summed up as follows : 
(1) The similar character of the ribbed periplast in 
Lophoinonas striata and in Polymastix. 
(2) Certain points of resemblance in the nuclei of the two. 
(3) The peculiar nature of the division process, apparently 
transverse,^^ in Lophomonas striata and in Polymastix. 
To this may perhaps be added the fact that Lophomonas 
and Polymastix, as far as the records show, are both 
parasites of insects only. 
Bibliography. 
Alexeieff, A. — “ Notes sur les Flagelles,” ‘ Arch. Zool. exper.,’ T. vi, 
No. 14, pp. 491-527, 15 figs. (15*11). 
“Sur quelqiies nom de genres des Flagelles, etc.,” ‘ Zool. Ang.,’ 
Bd. xxxix, pp. 674-80, 2 figs. (1912). 
Biitsclili, O. — ‘Bronn’s Klass. u. Ordnung.,’ 67, Protozoa, p. 843 (1884). 
Doflein, F. — ‘ Lehrhncli der Protozoenkunde,’ Jena (1911). 
Grassi, B. — “Intorno ad alcnni Protisti endoparasitici,” ‘ Atti Soc. ital. 
Sci. nat.,’ xxiv, p. 172 (1882). 
Hamburger, C. — “ Uber einige parasitisclie Flagellaten” (Vorlaufige 
Mitt.), ‘ Yerliandl. d. Naturhist. Medizin. Yereines zu Heidelberg,’ 
xi, pp. 211-19, 1 pi. (1911). 
